Sensor Formats: Depth of Field, Focal Length, F-Stops & Image Quality - Equivalence?

[@ThomasEisl.Photography]

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[@ThomasEisl.Photography]

Ja, das geht leider irgendwie nicht anders bei diesen Plattformen. Danke Dir auf jeden Fall trotzdem, ich weiß das sehr zu schätzen! Schön, dich "am Kanal" zu haben!

[@benauer3431]

You have the best, no hype videos about these topics (sensor and system comparisons) I’ve seen on KZbin. Just calmly explaining. Keep it up!

[@ThomasEisl.Photography]

Thank you very much! That means a lot, thanks for the feedback!

[@chrispatmore8944]

Hooray!! Bravo!! Someone on KZbin who knows what they’re talking about, and understands the fundamental physics of photography, rather just spouting marketing misinformation.

[@ThomasEisl.Photography]

Thank you very much - that is actually a very nice compliment. Thanks!

[@paulisraelsonisraelsonlaw654]

Thomas: Once again, you have debunked sensor size misconceptions in an unbiased and easily comprehensible manner. Thank you for the education. PJI

[@ThomasEisl.Photography]

Thank you very much! Your kind words are very much appreciated!

[@donaldpirie5485]

When I watch your videos, I am treated to an exceptionally well informed lecture. You have a gift not only in understanding your topic, but a gift in presenting the information in a way that is so clear that what you are discussing becomes obvious! If I could only follow only 1 channel, it would be yours. I learn more in a single lecture you give than anywhere else. What’s more - it is an absolute joy to have you as a teacher. Thank you.

[@ThomasEisl.Photography]

Thank you very much for your outstanding comment. I very much appreciate your words and I am truly honored. Thank you very much for recognizing my work, it is a pleasure to have you in the audience! All the best, Thomas

[@ThomasEisl.Photography]

Thank you so much!

[@TarrelScot]

A very interesting (and relevant) video for me, as I'm considering switching from my Fujifilm medium format system back to the APS-C system (at 40 megapixel). For me, the "double page spread as gold standard" was especially useful and I will now use that as a benchmark when judging my own image quality. Of course, there are many other variations that different sensor formats introduce. For me, the size and portability of the camera system has an impact on image quality (perhaps not technical image quality, but my ability to get a passing shot, try different compositions and just be generally more "light on my feet" as a photographer). Having switched up to medium format, this factor has had more of a negative impact on my photography than I expected.

[@ThomasEisl.Photography]

Hey Mark! Thanks for sharing that - I agree, size and weight are crucial. And although digital medium format truly delivers impressive IQ - clearly outperforming MFT/APSC/FF, the price you pay is in kilos :-) I'm quite sure that you will be fine with the APSC system as well. Your back might thank you. Cheers and thanks for contributing!

[@JeffreyMcPheeters]

Thanks for explaining this so well. Thanks to you, I have been presented with a visualization of what I read at resources like Cambridge in Colour but more comprehensible (sometimes I watch more than once to make sure I'm getting most of it right). There has been quite a lot of accumulating misunderstanding in the craft, especially in the digital age. Not sure why that is. I suspect so many enthusiasts with only a cursory or nonexistent film camera background in the fundamentals (of how the camera worked for decades before it became a computer with optics) has allowed some myths to develop and the Internet can quickly imbed a common explanation into the general consensus before it's been thoroughly vetted or peer reviewed. Well, I think I also believed some myths from the film days, however. Your channel is important to help correct these misunderstandings so photographers are able to solve problems without getting distracted and possibly spending money on a fix that won't fix anything. I'm not sure if I would ever get used to using field of view comparisons as angles of view, other than in astrophotography sometimes, because in a lot of the stuff I do in nature and action, cropping generally removes any way to compare images with a good frame of reference. So I simply refer to the actual lens focal length, the camera I'm using, and aperture and shutter speed and ISO. The actual focal length and format may tell me something about the story.... how much magnification was applied and possible depth of field guessing from typical distances, either known (a soccer field or tennis court is only so big), or the photographer notes their distance from the wildlife or scene. In landscape work, for very grand scale scenes, it's common to make wide panoramas from individual telephoto frames. So the difference in perspective might be insignificant between two different compositions, but much different in scale due to possible differences in magnification applied to individual frames. In a lot of the nature and wildlife work I have done, there is no way for anyone to pick which kit produced a particular image. In sports and event action work, there is some noticeable ways to distinguish or guess at some aspects but it's still only an educated guess which a skilled photographer will likely be able to render unimportant in the final analysis.

[@ThomasEisl.Photography]

Thank you very much for watching Jeffrey! Cambridge in color is a great resource. To be perfectly honest - I also followed many myths in the past years. You have to pay very close attention as some of these misconceptions sound very believable at first, but upon closer inspection, well - they turn out to be wrong. Also, I completely agree that using angles of view is cumbersome, as no one really uses it. It is always the "its a 50mm" that we use. Regarding distinguishing different sensor formats - I also agree. And I would not dare to guess the sensor format based on the final image. I think it is mostly important for the photographer him/herself as it might change the way of working a bit. Just yesterday I shot a studio session with medium format - of course with plenty DOF. I could have taken the same images with M43 and they would have looked almost indistinguishable in terms of overall look. Thanks for your extensive and relevant comment!

[@SpinStar1956]

Great video and explanations-thanks! Another factor, that plays a huge roll is that of software. Software is becoming the dominant factor in so many systems. And there are really an elite-tier that are actually more software artists, rather than simply software developers...

[@Henry30065]

Thomas, I continue to find the clarity and the preciseness with which you describe, in some cases, highly technical photographic processes, astounding and a real breath of fresh air! I was definitely one of those that was totally convinced that you could only obtain the best image quality with a full frame (or even larger sensor) camera and that all APC and MFT sensors were somehow inferior. Indeed, I purchased a 61MP camera for this reason, which now, thousands of images later and having seen your video, I think may have been a mistake. Thank you for helping to clear up so many misconceptions. Alun

[@victorlim5077]

Agree with your assessment. Don't chase the Megapixels. I am still using my 24MP Nikon Full Frame camera. Mainly for the Bokeh.

[@TL-xw6fh]

It is true Alun that we are influenced by KZbinrs and the camera manufacturers that more is better, bigger is even better and newer is even best of all! I've learned the hard way too. I use MFT, APS-C and so called full frame cameras today (because I never sell my cameras!), and like Thomas, I find it difficult to differentiate image quality, so long as I expose and focus properly and use quality lenses. I decide on what camera to use dependent on what I want to do (street, portrait, landscape, travel etc) and how portable I need the equipment to be.

[@markusbolliger1527]

@@TL-xw6fh Very smart your strategy 👍👋

[@ThomasEisl.Photography]

Hey Alun! Thank you so much for sharing that - I appreciate your honesty and I am honored by your positive feedback. No matter whether you will keep the 61MP model or get a different camera, the most important aspects are: Do you like working with the camera? Do you want to bring the camera along? Does the camera support your creative process?

[@johnehman8685]

This is the clear, concise, and practical analysis that has been needed for years! Virtually all cameras of these days are extraordinary. The key questions are: Which one is the tool that feels best in your hands, is most suited to your eye, fits within your budget, and gives you an artistic experience that nurtures your creativity? Thank you, Thomas, for your technical expertise, and even more for your obvious love of photography itself.

[@ThomasEisl.Photography]

Thank you very much John for your much appreciated feedback and your kind words!

[@zadnitsa]

Incredible content, thank you Thomas. As a newbie in photography, the confusion in terms of a lot of bloggers confused me very much, and despite the very simple sound of the words, I got a little confused, and when I started studying the topic of m43, I did not understand something and partially still not sure how some things work, only school knowledge of physics saved me from learn really strange approvals from some people. Thank you again.

[@zadnitsa]

And I really like your style of speaking and accent :)

[@ThomasEisl.Photography]

Thank you so much - great to have you on the channel and thanks for the kind comment. To be perfectly honest, it really all comes down to the final sentences: 1) Bigger is better 2) Better is almost never needed 3) Every sensor size will look at least a little bit different - pick your poison haha

[@zadnitsa]

@@ThomasEisl.Photography Yes! Big good for show off like oooh I'm a guy with biiig lens I'm so professional I have for me 1 big rule, and this rule destroys all debates about gear: If photo is great and stays in history and human minds, no one cares about sensons, lenses, quality, megapixels, sensor/film size, sharpness and even focus and colours. More important have a composition, emotions and history context. Okay, we don't shoot every day a greater images in history (we all have a chance, but I wish no one have a chance photograph a specific thing what human eye catches - wars and other things is not good). Well.. Emotions, idea, composition, catch a moment and other things still more important when super-wow lmao sharpness. Base quality is ok. And even we talk about work, really who cares if quality is just good (AI and softs today can do almost everything with even old camera RAW. When I just started my shots were just little not in focus. And this can be fixed..). I think we should talk about flexibility and comfort for shooter (I love wildlife, but go 1-day hiking and have a weak back. Well I should think about sensors BIGBIGBIG and dof or weather sealing, flexibility and lightweight? It's individual for every human, but always a simple) About work. I know a girl who shoot pets portrait (full body in studio), and she have ff, when crop camera. And really I and no one don't cares. If she go to even old m43 no one say a word, we want result, not sensors as a client. It's cool when now people talks about this more and more, when m43 have so more cool abilities It's simple. But gear talks like a toxic snakes or dog battles like console vs computer sony vs xbox in gaming or samsung vs apple (nikon vs canon old battle lmao) Sometimes I think some people needs a therapy with wathing what photos can be shoots on smartphone or compact camera or cheap 30$ china cameras (I saw wildlife photography awards, and I saw photos on really cheap old kit lenses or superzooms. In low light and crop cameras. With fast birds. And no one can say what gear is used before specific searching this) We live in century when everybody can afford a camera, and what a strange thing have a talks about gear like this, help corporations sell unnecessary

[@Superz3ro]

Fortunately you have stumbled on this path of your photography journey… 🤔

[@zadnitsa]

@@Superz3ro hmm?

[@mxyptlk]

Bravo Thomas....superbly explained...cold hard facts there's no getting away from them....

[@ThomasEisl.Photography]

Agreed Gerry. The facts are sometimes "hard to swallow" haha. Thanks for your kind words!

[@alecstewart9099]

The recent series of videos you have produced have all been very informative and useful. Having used medium format through to micro 4/3 myself I tend to agree with your final conclusion. Do not spend time worrying about image quality take pictures instead! Excellent work look forward to seeing more.

[@ThomasEisl.Photography]

Thank you so much Alec - that means a lot and I am very happy to read that you came to the same conclusion in your work. Best wishes and hope to read from you soon!

[@MarceloTezza]

That's a great topic to cover! A classic missconception between Fov and Focal Lenght. Great video!

[@ThomasEisl.Photography]

Thank you very much!

[@audaxrandonneur]

Thank you for this very in-depth video. Unfortunately, the majority of KZbin photographers never seem to have really learned their craft. Watching the video reminded me very much of the old days of analogue photography. A lot of basic knowledge seems to have been lost with digitization. My departure from Micro Four Thirds cameras stems from the fact that there is very little latitude in aperture selection before diffraction effects kick in. Cameras with APS-C sensors offer at least one aperture more leeway. Finally, I would have wished that image processing had not been equated with the sensor. The various manufacturers differ enormously, especially when it comes to image processing and the resulting colors and contrast curves (e.g. Olympus/Fujifilm versus Panasonic/Sony).

[@TL-xw6fh]

On your last point, it is true that every manufacturer have different algorithm in their software design and it is impossible to produce identical results. I use Affinity Photo to process the raw images from my Olympus, Panasonic, Fuji and Nikon cameras but switched off all default adjustments. I then apply my own adjustments or presets (LUTS in Affinity Photo) so that I can render the images the way I like. Try it!

[@ThomasEisl.Photography]

Hey Jochen! Thank you for sharing these very valid points - with the diffraction remark, you just inspired my next video btw! I agree that lots of basic photography skills have been lost or at least not properly cultivated in the digital age. I agree with the tip by TL, Affinity Photo is very good. Cheers!

[@bobhinderholtz3206]

Thanks!

[@ThomasEisl.Photography]

Thank you very much for your kind support! I very much appreciate that!

[@barrieharwood5645]

As always, a brilliant video. Concise and illuminating

[@ThomasEisl.Photography]

Thank you so much Barrie! Thanks for taking the time to leave this kind feedback!

[@mdrinkwater]

Thomas, thank you for debunking much of the nonsense around equivalence - I, for one, have learnt a huge amount watching this video. I would also like to compliment you on your superb command of English and ability to explain so clearly such complicated subject matter.

[@ThomasEisl.Photography]

Thank you very much for the kind words - it is great to hear that the video was beneficial!

[@Stephen.Bingham]

For me "equivalence" is an important creative tool (not just for choosing the most appropriate camera for a particular task) - if you understand it you are more likely choose the most appropriate parameters to get the image you are looking for. For example, if you understand depth of field is determined by aperture size only, you will choose a numerically smaller f-stop on a small sensor camera to get the same depth of field than you would on a large sensor camera. You will therefore get the creative "look" you are aiming at. I'm also a professional as it happens - a professional designer of optical instruments for Physics Research... My suggestion is people focus on these key statements: - A set of parameters are said to be "equivalent" if they create an image that looks the same (Same field of view, depth of field, and image blur (shutter speed)). It is a concept that is only relevant when comparing cameras with different sensor sizes. - Depth of field is determined by the the physical size of the lens aperture. Sensor size has no affect. f-stop and focal length have no affect on depth of field as long at the aperture size remains constant. - Light gathering power determines the total amount of light incident on the sensor. It is determined by the aperture size and the field of view. Sensor size, f-stop and focal length have no affect as long as the aperture size and field of view remain constant. - Combining the previous two statements we find that Light gathering power is constant for a fixed depth of field and field of view. - Low light performance is determined by the light gathering power and the sensitivity of the sensor. For sensors of a given technological generation the latter is often roughly constant - it doesn't depend on sensor size. Combining with the previous statements, we find that the low light performance is roughly fixed for a fixed depth of field - independent of sensor size. - Image quality is a move complex thing, but essentially it's usually easier and cheaper to construct high resolution lenses for larger sensors than for smaller sensors. This is especially true when comparing lenses with a particular entrance aperture and field of view for different sensor sizes. - In addition to the lens design issue (above), dynamic range and read-out speed may affect choice of sensor size in some applications. Hope that helps!

[@ThomasEisl.Photography]

Great contribution - thank you very much 📸👍

[@lxhk3595]

Condensed knowledge. Nice niche which I enjoy from time to time.

[@ThomasEisl.Photography]

Perfect! You are more than welcome!

[@PhotoArtBrussels]

Excellent video! Thanks!

[@ThomasEisl.Photography]

Glad you liked it!

[@ianroe1076]

I'm very happy to see someone profess that non-quality related features should be more considered than strictly looking for the best image quality on the market. I don't think very many photographers consider that a camera they hate using, or even just one that doesn't excite them to take pictures, isn't very useful even if it takes pictures sharp enough to turn into billboards.

[@ThomasEisl.Photography]

Absolutely agree Ian! Thank you for the comment!

[@siegfriedwiese7598]

estoy apreciando muchisimo sus conferencias en video. Usted es un grán profesór y me ayudó mucho entender el systema fotografico que estoy utilizando. Muchas, Muchas gracias!

[@ThomasEisl.Photography]

Thank you very much! Muchas gracias!

[@curts3054]

An excellent tutorial! All the information was clear, concise, and accurate. Now for my one quibble. I was heartened at first by your use of the term 35mm to describe the Nikon sensor. However, I noticed that you moved to use "full frame," during most of the rest of the presentation. Terms like full frame, FLM, and crop factor were introduced to help users of the 35mm format understand how their lenses would perform on digital bodies that had smaller image areas (sensors). If you really want to go to the origins, the term Full Frame goes back to the movie industry, where it referred to using the full gate of the film. While it was 35mm film, it was 4/3 in aspect ratio because the film travels vertically through the gate, not horizontally. As a result, the actual image was about 18x24mm, not 24x36. In photography, the term full frame originally meant that the image circle of the lens(es) covered the entire film frame (and now sensor), but did not exceed it. In this sense, 35mm and micro-4/3 are both full frame as their image circle matches the sensor size. , When it started, APS was not. as the 35mm lenses first used on APS exceeded the sensors by quite a bit. Later, lenses were released that were designed to match their image circle with the size of the APS sensor, thus thy also became "full frame" in the original meaning of the word.

[@ThomasEisl.Photography]

You are absolutely right - when I started the channel I told myself to never ever use the term full frame ever, just because of the reasons you thankfully and correctly pointed out! The term is so widespread, that I am afraid I will have to bring it up from time to time, either by accident or intentionally to make my references understandable. In any case, my inner rebel will make me say 35mm as often as possible, as ai feel exactly like you about it! Thanks for the nice comment and feedback!

[@Drmikekuna]

I love these videos, they are so logical and well-put together. Thank you. I did a video a number of years ago challenging the idea of "equivalent F stop," and you wouldn't believe the hate I got. Some folks like to hold on to incorrect beliefs. It is true that all camera systems can take excellent photos. Just as important as the sensor is the microprocessor and its software. Keep up the great work.

[@ThomasEisl.Photography]

Thank you Mike! I cannot agree more with what you have stated. It is unfortunate that you have experienced such "feedback". Usually when people get very upset it is because they are dealing with cognitive dissonance. We just want to believe what we have believed so far. The other factors you have mentioned - totally agree. This obsession with "which sensor" and "which size" ignores too many factors, unfortunately. I think you will appreciate the next video. It is also a controversial one hehe Thank you very much for your continued support and feedback, it is just amazing to have you on the channel!

[@RogerBenno]

Thanks for this. Hopefully this video will be widely watched. I have come from a film background (I have been using interchangeable lens cameras for 30 years. In the film days we never had this nonsense about what format to use. You went with what you could carry and what the end medium would be. I think it's such a shame that we have KZbin influencers who are trying to get the amateur photographers to buy cameras that are way too big, expensive and advanced for what they need. Let's get back to taking photos, and if there is any discussion needed about gear let it be about lenses and the durability of the system.

[@ThomasEisl.Photography]

Roger - thank you very much for this comment! I cannot agree more. Your words echo the planned direction of the channel. I much appreciate the invaluable input of a long-time professional like you, thanks again and hope to hear from you again in the future!

[@TL-xw6fh]

Thank you once again Thomas. You make sense of the nonsense spewed on KZbin by people who profess to be so-called experts (here's referring to you DP Review and Tony Northrup). I learned my photography the hard way through 40+ years of analogue photography and textbooks, so I am fully versed and understood everything that you said here. Unfortunately, current day photographers mainly learned to shoot in digital medium and slavishly follow such influencers who themselves do not understand the physics of photographic equipment. Sadly, what you have just said will mostly fall on deaf ears because these influencers are way too powerful in their influence. In any case, do continue to tell the real facts, and I do that to everyone who ask me such questions about equivalence! I just tell them everything is relative, just like what Einstein taught me!

[@ThomasEisl.Photography]

Thank you very much, I'm truly honored by such a comment - first, because of the positive feedback, and second, that you approve my statements. I really think that working with analog first really teaches you how things work, because trial and error does not really work. If you shoot film, you have to know what happens inside the box before you press the shutter. Thanks again and I'm glad to have you on the channel!

[@metalmick99]

Thanks for another thought-provoking, well-explained, and well-reasoned clip, that was also very enjoyable, Thomas. I think I detected too, an instance or two of dry humour which is always welcome. As always, looking forward to your next clip.

[@ThomasEisl.Photography]

Good morning Micheal! You are absolutely spot on regarding the humor ;-) Thank you for your kind words and hope to read from you soon. Best wishes, Thomas

[@jclaybaugh2]

Well done, I shoot all of these formats and besides some real corner cases the best advice is to use what works best for you.

[@ThomasEisl.Photography]

Completely agree - thank you very much for sharing that!

[@BarryCarlton]

Bravo! I particularly like your point that image quality doesn't scale linearly. That, combined with the fact that an image doesn't exist in the abstract, but instead must be somehow reproduced to be used, and that reproduction methods have their own limitations, means, as you say, that pretty much any camera format can give you what you need, so the choice comes down to things like ease of use, preferred aspect ratios, and the way a particular sensor renders colors. I just finished putting together a photo book for a music festival, with the book including a number of photos taken backstage during performances. The photos are all taken in extremely dim light, and by conventional wisdom, my little micro 4/3 system shouldn't have been able to handle it. But it did, and actually better, for my purposes, than I could have achieved with my full-frame camera. For two reasons: better image stabilization, and better across-the-frame sharpness. Sure, the full-frame camera images would have had less noise, but the micro 4/3 images were fine for conveying what I wanted to convey. Also, in my case, my full-frame camera is a DSLR, which means I could not have been silently photographing there backstage. Again, the smaller camera was able to provide what I needed.

[@ThomasEisl.Photography]

Awesome to hear! I had very similar experiences in practice - the problem with smaller systems is that we tend to zoom in way closer than we actually ever print / reproduce the image. Then we start worrying about noise and so on, although it is not a real issue. Thanks for sharing that!

[@ansomeBob]

First-class video as usual, thank you so much for the excellent way you explain things.

[@ThomasEisl.Photography]

Thank you very much, I'm honored, thanks for watching!

[@tobias6875]

Perfect well done

[@ThomasEisl.Photography]

Thank you very much!

[@vancouverbluesea]

Interesting thoughts. At the end - perception is very subjective.

[@ThomasEisl.Photography]

Agreed! Thank you

[@alanjones3454]

Thanks, Thomas. Unfortunately too many people new to photography - and especially digital photography, with no previous experience of film and film cameras - will fall under the spell of the "influencers" on social media platforms and blindly aim for the most advanced and expensive equipment . Your point about the way an image is viewed is just as important as the way the image is taken can't be emphasised enough . I was watching a YT review recently and I was thinking how poor the photographs taken with a m4/3 camera were. Then I realised that YT had defaulted to the horrendous auto 360p. Once I'd reset it to a higher rate of 720p the photos came to life and were more like what I expected to see . It's the modern day equivalent of a good analog photograph being ruined by bad processing .

[@ThomasEisl.Photography]

Good evening Alan! Thank you very much for sharing your thoughts - could not agree more. It is amazing to see that a new generation of photographers is discovering film, so they can learn the same way we did. It really makes you a better photographer, I'm convinced about that!

[@josecolon8143]

Bravo, bravo, bravísimo 👏👏👏👏👏👏👏👏

[@ThomasEisl.Photography]

Thank you so much!

[@josecolon8143]

💎💎💎💎

[@Carolyne_games]

Thanks for debunking all the myths around sensor sizes 😊I played around with FF for a couple years and recently returned to APS-C, feeling that it’s the sweet spot for myself (and likely many others). I feel that what’s often overlooked by many consumers is that smaller sensor cameras tend to perform worse not really because of the smaller sensor, but due to the fact that FF is easier to market at higher prices and the corresponding lenses are therefore often equipped with better optics. A M43 or APS-C camera with a great lens can definitely outperform any FF with a mediocre lens!

[@ThomasEisl.Photography]

Thank you very much for your kind words and sharing that! I agree, there are many factors to consider. Mostly, it is marketing and lack of knowledge that leads to the "FF is best" statement.

[@macwestcanon]

your the best on you tube

[@ThomasEisl.Photography]

Thank you so much! That means a lot to me!

[@j.joe.b3384]

I just printed 12 in x 18in (~30cm x 46cm) image from a 16MP m43 camera. Based on preconceived notion, I was prepared to see pixels if viewed up close but was pleasantly surprised the print looked great any any viewing distance. Love your content.

[@ThomasEisl.Photography]

Great to hear! I have printed 12MP MFT on 50x70cm for an exhibition - no one noticed a lack of anything, really. Thank you for sharing your experiences and the kind comment!

[@Drmikekuna]

I have a large photo printed on canvas hanging in one of my bathrooms. People comment that they love it. What did I take it with? A Pentax Q mini DSLR that has a 1/2.3 sensor! The folks who like it are not pixel-peeping, they are looking at the total composition, which is pleasant and relaxing (I guess that latter is good for a toilet picture).

[@simonpayne7994]

Coming originally from "full frame" analog transparencies, and after a long, long pause, I landed in the middle of the digital world. Having grown considerably older on the way, I had to radically cut down the weight of my gear. After a few trials and errors I finished up on a single zoom lens and 1" sensor as stuffed into the dinky Sony RX100m3. Recently I "upgraded" to a RX10iv with more zoom and same size sensor. As far as picture quality is concerned, there is nothing lacking and a resolution of 20MP allows enough room to crop in a bit if needed. A double page spread would never be an issue. I would like to point out that 1" is smaller than MFT, which is smaller than ASP-C, which is smaller than the so-called "full frame". Even my 12MP Zenfone 4 with a 1/ 2.55 inch sensor is fully adequate for taking flower bloom close-ups to be displayed at up to about A4, although, in direct comparison, here you would see the difference. I have always thought that the performance of small sensor systems is better than their reputation. Thomas has in his excellent video just proved my suspicions. Of course, the limitations of my smartphone camera are quite obvious. But on my Sony 1" cameras you do not really need a larger sensor or any higher resolution. For all practical purposes the quality of the captured images is more than enough. And the optical zoom range that becomes possible with the 1" sensor on the RX10 from equiv. 24mm to equiv. 600mm is more than just useful.

[@ThomasEisl.Photography]

Thank you very much for sharing that - I cannot agree more with all you have stated. And really, the Sonys are perfectly fine, as you've said. I'm thankful for you sharing your extensive experience and your findings - we both came to the exact same conclusions, that is great to read!

[@simonpayne7994]

@@ThomasEisl.Photography If I were a professional photographer, of course, I would have to use the heaviest, most impressive gear I can get my hands on. My two completely superfluous assistants would then wheel it all in on trolleys, just to impress the customer. 😀 In reality, as far as product photography is concerned, the most important issue by far is the lighting and a couple of interesting props. As a camera, at least in a tabletop situation, any of the leading smartphones would more than suffice. The larger DOF could even be to my advantage.

[@ThomasEisl.Photography]

I'm still waiting for a client that will pay for two assistants haha 😆 I prefer bringing smaller camera and keep the money for me haha 😂 Agreed regarding the DOF

[@simonpayne7994]

@@ThomasEisl.Photography And when you are finished the customer invariably picks out the wrong picture! (So hat man es mir berichtet. 😁)

[@ThomasEisl.Photography]

True!

[@martinhommel9967]

Thanks for your excellent explanations. In my opinion there’s too much misinformation about and owners of crop sensor cameras are made to feel inferior. In reality there are so many excellent systems around. Pick the one you enjoy using the most

[@ThomasEisl.Photography]

Agree 100%! I am perfectly confident to shoot every professional assignment with MFT. Having shot ultra LL fashion shows with the OM-1, competing directly with other photogs with FF mirrorless, my images ended up printed in the exhib of the designers, theirs did not. There is no real limitation, if you know what you are doing. If you don't know what you are doing, no camera in the world will save you. Thanks and best wishes!

[@mggerlach]

Congratulation for this outstanding lesson. (and I like your austrian accent.)

[@ThomasEisl.Photography]

Thank you very much Manfred! Ha, I tried to hide the accent - did not work it seems :-)

[@ppzart]

Thank you Thomas! A good wash up of many misconception and half-true statements. I would love to see a video from you on the different dynamic and Tele-compression effects in professional portraits the different systems favor. The main portrait lens offerings offer different strengths according to shooting distance, too.

[@ThomasEisl.Photography]

Thank you Piotr! The video idea - noted (!). It might take a while to put it all together - but I agree, this is just a very interesting and relevant topic that should be systematically evaluated.

[@andy.underwater.videos]

Excellent Information and so well explained. 😃

[@ThomasEisl.Photography]

Thank you very much!

[@allanc803]

Buy a system, learn to use it, have fun. Everything in life is subjective, get used to it. love your channel.

[@ThomasEisl.Photography]

Well said!

[@markusbolliger1527]

I agree with every point you make! For nearly all purposes the image quality of all up-to-date camera systems from mFT to medium format is good enough and the output practically indistinguishable. Nevertheless I prefer full frame for two reasons. First the files are more flexible in post production - it is easier to get the result I have in mind. Second reason: Even with my f/4.0 full frame standard zoom lens, - the Nikkor Z 24-120 F4 S, - I can get a shallower depth of field than I could achieve with a f/2.8 zoom in the mFT system. Which allows me to isolate better the main motif from the background and thereby achieving a more threedimensional look to the image. With a f/4.0 zoom in the mFT-system I get too much depth of field in some situations - I can't get less of it. On the other hand I can always stop down a full frame lens if I need more depth of field.

[@ThomasEisl.Photography]

Thank you very much Markus! A very thoughtful and relevant comment, I totally understand! Every photographer finds his own "sweet spot", much like in film photography when some shot 35mm, and others prefered 645 or even 6x7. Thanks for contributing on the channel in such a great way, and thanks for watching!

[@LarryFasnacht]

I wish we had settled on angle of view a hundred years ago when this first started.

[@ThomasEisl.Photography]

I completely agree Larry!

[@artsilva]

I hope this video gets some traction because I couldn't have presented this any better. I have been arguing these same facts for years with people online who are misled about sensor formats and lenses, mainly on the subject of "equivalent" apertures across the sensor formats to get the same DoF without taking into effect of distance to subject. Also the light gathering is the same across all formats in a given aperture "per unit area" like you said. Total light gathering on the sensor size is what confuses people so I like to say that Scene Gathering because when I say more Total light on larger sensors, some take it as more light intensity which is not the case. It is why I always say that on a hand held light meter there is no setting for sensor/film size. An f/2.8 at 1/1000th sec. setting is f/2.8 at 1/1000th sec. on any sensor or film frame, it's the angle of view and/or subject distance that has to be equalized. I think most new photographers are not educated on the physics of optics and light measurement which is why there is so much confusion and misinformation being spread by bad advise on some YT channels, it gets frustrating when I try to explain what you eloquently presented in this video... Well done!

[@ThomasEisl.Photography]

Thank you very much! Could not have said it better, I very much appreciate your contribution and kind feedback!

[@TangerineTux]

What do you mean by “without taking into effect of distance to subject”? Equivalence _assumes_ the same distance to the subject, otherwise the perspective is different.

[@artsilva]

@@TangerineTux Not when people are arguing DoF when matching compositions. There is a lot of that mis guided "equivalence" on many YT channels and the minds of people who watch and believe them. You do a portrait of someone beginning with an FX camera then switch to a DX camera, same lens [or just go to crop mode on the FX] and find that you need to take a couple steps back, thus effecting camera to subject distance and DoF. Nothing changes in the lens and the camera except cropping the composition due to less area of the sensor covering the lens image circle. It's like putting barn doors on your glasses, you see the same but the edges of your FoV are being closed off.

[@rudyhulsmans7443]

Equivalence fans will not like your message, but I do think you have a point. I had a coffee while watching and I treated you to one too...

[@ThomasEisl.Photography]

Thank you very much - also for the coffee! I quite like the fact that every format has its unique look.

[@theoderzweite8272]

Lieber Thomas, vielen Dank für dein Engagement, Klarheit in das Theme Äquivalenz zu bringen. Deine sachliche Art verhilft zu einer deutlichen Versachlichung des brisanten Themas "Systemvergleich". Ich befürchte allerdings, dass deine Feststellung, ein größerer Sensor kann mehr Licht erfassen physikalisch nicht ganz richtig ist. Denn Licht ist nicht allein durch die bestrahlte Fläche zu bewerten, sondern auch durch die darin transportierte Energie. Eine 60W Lampe leuchtet einen kleineren Raum besser aus als einen großen, und hat doch dieselbe Energie.... Ein Kuchen schmeckt nicht einfach dadurch besser, wenn er größerer ist, sondern wenn die Aromendichte höher ist. Ein Wert, der eben auch wichtig ist, ist das Auflagemaß - der Abstand von Fokus- zur Sensorebene. Ist der Bildwinkel gleich, erfasst ein kleiner Sensor bei gleicher Blende nicht weniger Lichtenergie als der größerer, weil sich dort die Lichtenergie auf einer größeren Ebene verteilen muss.

[@ThomasEisl.Photography]

Hallo Theo! Danke dir! Ich denke das ist ein Missverständnis - genau diese Angelegenheit spreche ich an - "regardless of size ... collects the same light per surface unit" (aka f/1.4 ist f/1.4) LG Thomas 📸 Und danke für die netten Worte!

[@edzardpiltz6348]

Hi Thomas, thanks for the detailed comparison. But when it comes to DOF I still remain confused. In Streetfotografie I use some focusing and therefore need to calculate my DOF all the time. On mft I find myself always shooting to stops lower than on (nowadays called) FF. I don't know about the "typical" look of either format, but my results do look so similar that I can not tell the format they are shot on🤔

[@ColinMill1]

I totally agree with your conclusion. In the end all photographic images ultimately go through the same filter system - the Mark 1 human eyeball. This is a great leveller. I think we have become too obsessed by image quality. If current full-frame image quality is to be required before a photograph is to be considered worthy of viewing then we would need to discount a very high proportion of all photographs taken in the 20th century. It is interesting to consider, for example the quality of the Nikkor 50mm f/1.4 lens that was introduced in 1962. Vast swathes of the stunning images published in National Geographic in the 60s and 70s were taken with this lens and yet it is now considered "unusable" by many modern day photographers.

[@ThomasEisl.Photography]

Very well said Colin! Could not agree more!

[@ThomasEisl.Photography]

I will feature many vintage lenses and examine their unique qualities on this channel - the look and character of those is often very desirable and the performance of them is also impressive, in most cases!

[@ColinMill1]

@@ThomasEisl.Photography I look forward to seeing these videos. Can I suggest the Nikkor 105mm f/2.5 (preferably in its early F-mount form) and also the Canon 50mm f/0.95. The latter is a lens I have only seen once, in a camera shop in Nairobi in 1964.

[@ThomasEisl.Photography]

@@ColinMill1 Ahhh, I would love those two. Unfortunately, I don't have those at the moment! But I'll be on the lookout. Those are legends!

[@sourcebased]

I often read about better or worse depth of field in such discussions but there is no such thing! DoF is an important aspect of composition, sometimes you need more of it and sometimes less. Also it is often forgotten that the same aperture, exposure time and ISO will give you the same exposure, regardless of sensor size. Larger sensors will and have to gather more light to get the exposure, resulting in better signal to noise ratio and the need of a bigger and heavier lens, as more light needs to be gathered. As Thomas correctly pointed out, each format will have its own „look“, but for me the most important aspect of equivalence is an equivalent composition, meaning the image looks more or less the same. To get a comparable DoF, you will need to change aperture and therefore the exposure will not be the same any more. So to go with Thomas example with 50mm f8 on full frame and 25mm f4 on MFT, and say a moving subject is dictating a fixed minimum exposure time, you will need to raise the ISO on full frame to compensate the exposure and get a comparable composition. ISO is the only part of the exposure triangle that does not affect composition. This need of higher ISO needed to get a comparable composition will balance with the better signal to noise ratio of the larger sensor, depending on its quality. There are some corner case compositions only possible with a minimum sensor size, as there is a limit to how bright a lens can be, but besides that the results in image quality will be much closer than most people think for any composition. Please correct me if I am wrong! 😊

[@ThomasEisl.Photography]

Could not have said it better - thanks for contributing! 📸👍

[@sourcebased]

@@ThomasEisl.Photography Thank you, that is just the confirmation of my reasoning that I needed! I started with Olympus, never switched. As an amateur, the equivalence discussions on forums made me think I might miss something important, so I started investigating and came to these conclusions. Of course I want to have all the other great systems but I don’t need them. As tempting as they are, switching systems won’t make me a better photographer. Still tempted by medium format, I don’t get why some push so hard for full frame, neglecting the „better“ options… too heavy?! 😂 Keep up your great work, I enjoy your channel a lot. ❤

[@ThomasEisl.Photography]

Agreed! Again, absolutely spot on - also with the weight. I find it rather amusing that FF should be the end all do all and the rest is either too small or too big. That is actually quite funny if you think about it, as you've said 👌

[@markusbolliger1527]

In the case you mention there is a tie between mFT and full frame - no winner here! To get the same DoF of a mFT 25mm f/4.0 lens with a full frame 50mm by f/8.0 you need to raise the ISO by two stops - which gives you approximately the same image quality. The advantage of full frame is that you can always stop down a lens to get mor DoF - but you can't open a mFT lens only to the maximum aperture, which is not faster as f/2.8 or f/4.0 for most zoom lenses. Thus you are limited in the choice of shallower DoF. Yes you can take a f/0.95 mFT lens, but this corresponds only to a f/1.8 full frame lens. There are no equivalents in the mFT system for full frame primes with f/1.4, f/1.2 and f/0,95.

[@sourcebased]

@@markusbolliger1527 You are right regarding the very fast primes, that have no equivalent regarding DoF in MFT. Regarding all other aspects f/1.2 will stay f/1.2 for the exposure - already a very shallow DoF on MFT and I do not have to stop down so much to get a reasonable DoF. I think full frame will have a slight edge regarding image quality still, at least with the most expensive top models. You get what you pay for, in money, size and weight. And the other features I might miss… never had to clean a sensor, stellar IBIS, weather sealing etc. 😂

[@photos4045]

I would like to use a micro 4 thirds because of weight but I do lots of 24x36 canvas prints. Would that work ok? Should I rent one and see?

[@ThomasEisl.Photography]

You should definitely do that. I've printed way larger with MFT in the past, there is no need to worry!

[@stehlealexander]

Fantastisch - thank you

[@ThomasEisl.Photography]

Vielen Dank - thank you!

[@lichtloper]

You say that Nikon's 50mm lens 'produces' a (diagonal !) field of view of 47 degrees on Nikons D800 and that Oly's 25mm lens (4:33) does yield that same field on Olympus' PenF-body. But should not ALSO the image ratio taken into account in this 'comparison'? [For me this is a rather essential element as I prefer images with a 3-to-4 ratiopresentation.]

[@ThomasEisl.Photography]

Very valid comment, thanks! So the universally accepted standard is to ignore aspect ratios as it only a unified (and therefore cropped) aspect ratio would allow for exact comparisons. But if you have a specific personal preference, then the sensor format matters as this means that you do not have to crop in post production - which is great because you get more image quality. I personally also prefer 4:3, by the way.

[@viktorpaulsen627]

Hi Thomas. Great video! I have a question about the part where you show the three pictures of the Canon 8mm camera side by side. The front of the camera, which shows the name Canon, looks washed out (white-ish, I can not clearly read "Canon") in two of the pictures and normal in one of the pictures. Due to this, only one of the pictrures look useable to me. Are all three pictures usable?

[@ThomasEisl.Photography]

Hey Viktor! The reason why one looks washed out is because of narrow DOF. It was more a theoretical example to give a comparison of IQ - the shot itself is not well enough lit for a real publication I'd say hehe. But in terms of IQ - all three of them are perfectly good, you can download them on my site!

[@datapro007]

Thank you Thomas. This video cements many of the thoughts that I have had about "equivalence". It is in fact a myth. I shoot MFT unabashedly because of the small size, light weight and excellent IQ.

[@ThomasEisl.Photography]

Thank you! MFT is a great system and capable of outstanding IQ and performance. Great choice 👍📸

[@LyndonPatrickSmith]

Great video Thomas! 17:19 Should that 3rd closeup image be listed as full frame since your first one was micro four-thirds? Or is the difference between #1 & #3 just high res mode? Cheers!

[@ThomasEisl.Photography]

Thank you so much for the positive feedback! It really was just two cameras - the OM-1 and the Pentax 645Z. The idea was to show that the OM-1 can really deliver more IQ in HighRes mode, actually punching above its weight! If I would have sharpened the HighRes file, this would have become even more obvious. But that would have been "against the rules". Cheers and thanks again!

[@frontstandard1488]

The Pentax Z image of double page spread was clearly sharper and better delineated. Obviously for most common viewing applications it's unimportant, but for print etc it could be important. There was a reason pro photographers used 6x7 and 5x4/8x10 transparency back when I learned photography as an assistant, and also as a lab technician in very high end labs. No publisher or art director would accept a 35mm transparency for most work except lower quality magazine publishing etc. High resolution allows the viewers to alter their viewing distance to taste and up close to see fine details, which is a creative choice. But there is an undeniable lushness to larger formats which I think draws some people. Horses for courses.

[@ThomasEisl.Photography]

Of course, a larger recording format (especially because of the lenses) will deliver more details - however, the relationship is not linear and there is a significant difference between digital and analog, as pixels are dimensionless while film is not. Also see:kzbin.info/www/bejne/emLIq5iqeqZ_oZIsi=G20Re5NyPqDNc2kN Thanks for the comment!

[@ruudmaas2480]

Perfect !!

[@ThomasEisl.Photography]

Thank you very much!

[@bkaustav]

Great content. 🙏👏

[@ThomasEisl.Photography]

Thank you very much!

[@AoyagiAichou]

When it comes to focal length equivalence (3:36), it's simply the easiest way to describe it. When I say that I have a 50mm full-frame equivalent lens, everyone knows what I'm talking about, unlike when I say my lens has 47° FoV. Unfortunately some let's say less gifted people misunderstand it and say that it's a disadvantage, that MFT cameras crop more. Which is nonsense, of course. MFT lenses are made with this in mind. Oh, and I definitely wouldn't say that those photos 16:32 are indistinguishable. There is a clearly a lot more detail in the second photo - that much is visible even when not playing this on fullscreen ("theatre mode", 27" monitor). Although I suspect this has a lot to do with the lenses used.

[@ThomasEisl.Photography]

Thank you for your comment! 1) Agreed - focal length is convenient. I use it as well. However, it can be really misleading if you do not keep in mind that FoV is the "real deal" 2) Agreed - there is a difference. The indistinguishable part is more referring to the 100% - actual print comparison. MF is very sharp even without sharpening applied. MFT is "in need of sharpening" - which I did not do. So, I should have said that explicitly! And yes, the OM was at a disadvantage with the zoom - it was a necessity to match the FOV, unfortunately. Thanks for contributing!

[@bkaustav]

I understand from where you are coming. What about new photographers who never used big sensors or film? If the beginner photographer starts with a smaller format what is the point of comparing focal lengths. Angle of View would be a better way.

[@AoyagiAichou]

@@bkaustav Well, that's because eventually t hey might start using different sensor size, or even merely talking to others. And basically everyone (including camera manufacturers) operate in full-frame equivalent focal length rather than FoV. If a beginner photographer asks me what FoV they should use, I would have to look the numbers up.

[@ReinoldFZ]

@Kaustav Banerjee exactly. I started with compact cameras, Even for film I use more compact cameras which have "5x" zoom or do. I don't see interchangeable cameras as upgrades and not interest in full frame. Although I know about focal lengths I honestly prefer the solution from smartphones and compact cameras in which 1x is around the 24mm equivalent,, 0.5x wide angle and 3x, 5x, 10x the telephoto. Reading OP's answer to you I think he believes there is a progression towards full frame ILC but that is not true anymore with MFT, 1", and Fuji aps-c lines with the lenses one will need to print big enough. Canon and Nikon somehow forced the "upgrade" to full frame by offering just not as good kit zooms. This without taking in account how smartphones have destroyed the market of compact cameras. My Samsung S20 FE is not as enjoyable as my Sony WX80 with its Carl Zeiss zoom but the image quality is better.

[@thijssiebeling5165]

Hi Thomas, thank you for teaching us! One thing I am still confused about is when for example Tony Northrup says "sensor size does not change the exposure in any way, but at the same time larger sensors gather more total light, so they can use a lower ISO". Is this true? How do these two statements not conflict? Also does it not take more light to project an equally bright picture onto a larger surface area vs smaller area, so in a way, is having a larger sensor not balanced perfectly between gathering and requiring more light at the same time?

[@ThomasEisl.Photography]

Ahhh, thanks for bringing that up! TBH, I think Tony caused more harm than good with the statement - and you just found out. Regarding "lower ISO" A larger sensor can gather more light in total - therefore, it is less noisy, has usually more DR and so on. It does not use a lower ISO - it is just "more efficient" at gathering light at the same ISO. What Tony probably meant was that larger sensors tend to have lower ISO limits. He probably wanted to indicate that these lower values are possible because the larger sensor is more efficient at detecting light. It might be somewhat true, but it is also a dangerous oversimplification, because a camera manufacturer can always offer a lower ISO number (sometimes at the expense of dynamic range) with a firmware update. So there are many many additional factors that come into play, that is why this statement is a bit over-simplistic and can cause major confusion. My video on dynamic range will definitely help to illustrate what I tried to write here: kzbin.info/www/bejne/q4qyo2mqbdGfncU&si=EnSIkaIECMiOmarE Regarding "more light" - you are right regarding the more light needed! The following variables define how much light a sensor receives: exposure time and aperture - meaning the physical size of the hole. Leaving SS aside, let's talk about the hole. The bigger the physical opening (entrance pupil), the more light. If you you look at the two f/1.4 lenses from the video, you will notice that the lens for mft has a smaller hole than the one for FF - because MFT is smaller, the lens does not have to collect so much light to (!) bring the same amount of light per surface area (!) to the sensor. However, the MFT lens does not project an image as big as the full frame lens. The f-number does not tell you how much light a lens collects, but how much light it collects per surface area (!). Therefore, a smaller sensor is not really more balanced in that regard, it just needs bigger lenses to get the same amount of light per surface area (!) - as it needs more light in total (aka a bigger hole). This is btw the reason for the size difference between lenses. To make things even more clear: If you put an FF lens with f/1.4 on MFT, you still don't get more light per surface area (!), but you will get a lot of light left and right of the MFT sensor that is of course not doing anything as there is no sensor area to detect it. More drastically: If I want a lens as small as MFT on a FF, it would have either abysmal optical properties or less light gathering per surface area -- aka the f/stop would not be f/1.4 but for example f/5.6 or worse. Regarding the "balance" Here is the bad news - there is no balance. Because in reality, the bigger the better. That is why analog large format is superior to even a Phase One IQ4 for 45.000 EUR. But, here is the good news: Bigger does not mean linearly better, but only incrementally better. That is why smartphone cams are relatively good compared to much bigger cameras, they are not 20x worse, right. Only a couple times worse. The "sweet spot" is subjective, but in reality, contemporary cameras are so good that there is absolutely no need to worry about all of this. They are just so good, that the real limitation is the print, the display and so on - not the camera. Let me know if I was "on target" with that reply

[@TL-xw6fh]

Tony Northrup was actually an engineer who happened onto photography. Now you know who you should be listening to instead. He has caused more harm to the photographic world than anyone else in history.

[@thijssiebeling5165]

@@ThomasEisl.Photography Excellent as always. Thank you for taking the time to answer!

[@viktorpaulsen627]

​@@ThomasEisl.Photography Are you aware that you wrote: "Therefore, a smaller sensor is not really more balanced in that regard, it just needs bigger lenses to get the same amount of light per surface area (!)"? Please confirm or correct. Thanks.

[@viktorpaulsen627]

@@TL-xw6fh What do you mean?

[@Cotictimmy]

Interestingly - you sometimes hear KZbinrs use the term 'Depth of Field' to mean more 'Bokeh' (ie the exact reverse of its traditional meaning.) Strange but true. 😮

[@RoderickJMacdonald]

And some go further, using “more depth of field” to mean blurrier bokeh.

[@ThomasEisl.Photography]

Yes! There are a lot of mix-ups floating around, I mean, mostly irrelevant in practice, but notable nonetheless!

[@TL-xw6fh]

Bokeh is an anathema to landscape photographers and yet KZbin influencers want to convince you that it is the be-all and end-all of photography!

[@okaro6595]

People associate more with better so when it is depth of field and they want more blur they say more depth of field.

[@Stephen_Baker]

Hmmmm. Perhaps two things (unless I misheard two of your statements);- A. [Trivial:] short focal lengths offer better DoF than longer. Eg Zeiss Distagon or Voigtländer native “short focal lengths), on Full frame or Micro Four Thirds. The shorter, the better DoF, relative / irrespective to these formats? Voigtländer is native to Nikon Z and MFT, for example, so the offer the same DoF equivalence? B. Please consider the HDMI standard published ca. five years ago; especially hdmi 2.0 and 2.1 (2.x massively increasing Mbps transfer speeds). You are right - analogue is still always better than digital (in any format) until digital reaches 8-10k, full gamut (!) at a certain bit depth, HDR etc. Large Format trumps Medium Format, trumps croppedMF and so on, on either the separate analogue or digital pathways. Meanwhile RAW may be good for sliders in Post but it still doesn’t match the human eye, compared to analogue (although prosumer printers at home are still a HDMI catastrophe; they don’t even have a roadmap)? Pro printing technology is perhaps another story, thanks to Adobe? I would therefore respectfully suggest that this ambitious video may need to be reconsidered, particularly toward the latter end of your otherwise excellent approach and thinking? Mfg Stephen

[@ThomasEisl.Photography]

Hey Stephen! 1) Interestingly, only the near-far distro of DoF is impacted by focal length, although very slightly. Here is the tricky part I only slightly touched: If you mount the same lens on different sensors and focus both times at the same distance, and then you enlarge the final images to the same size, the smaller sensor image will actually have less DoF (and a completely different crop). Same thing happens when you crop the image in post from a larger sensor. The difference is not really big, but it is there. The really important "metrics" for DoF are focusing distance and entrance pupil / physical aperture. If you examine a 35mm f/1.4 and a 105mm f/1.4 for the same sensor size, you will see that the entrance pupil of the 105 is way bigger than the 35. That is the main reason you get shallower DoF from the 105. 2) Yes - I have another video up which is about Dynamic Range, it is a bit in that direction, I'd say! What I really like about analog is that it does not really have "fixed values" it has to save. Although the practical difference is limited, I like the idea of "infinite gradation". From what I have read, I think we are on the same page - I'm not quite sure what your objections are. Thanks for contributing, feel free to further elaborate!

[@photos4045]

Thomas, what was the size of the prints?

[@ThomasEisl.Photography]

The double-spread was A3!

[@ianmeades6483]

I realize this comment may be slightly off topic, yet tangential related: I notice that the bit depth for Olympus MFT cameras is 12 bit, Nikon full frame is 14 bit, and Fujifilm medium format is 16 bit. Could you comment on how these differences might affect image quality? And if it does, under what conditions would it be of significance?

[@ThomasEisl.Photography]

Bit depth is more about gradation than about dynamic range - which sounds strange,but actually isn't - here is my video on that: kzbin.info/www/bejne/q4qyo2mqbdGfncU Having used various systems with various bit depth I can tell you one thing: The camera manufacturer makes sure that the camera has files with sufficient bit depth. No limiting factor here. More often than not, cameras have a higher bit depth than they can actually "record" / differentiate values. I think the video above will illustrate what I mean!

[@ianmeades6483]

@@ThomasEisl.Photography Ah! Thank you!

[@RoderickJMacdonald]

Thank you for this. After considering your explanations, I gather that “equivalence” is not and never was a technical term in photography. “Equivalent” means the same but different (in general, not as a photographic term). A 45mm lens in M43 is a different focal length that 90 in full frame, but gives the same field of view. I would say that one is equivalent to the other because the 2 dimensional compositions are the same. Is that wrong?

[@ThomasEisl.Photography]

Absolutely, there is definitely equivalent FOV, as you stated - however, the 90 and the 45 lenses you mentioned, they will never look exactly the same. Although they can look very similarly. It is splitting hairs, but I wanted to make this point nonetheless as this whole sensor comparison thing is getting completely out of hand IMHO. Thank you for watching and for contributing!

[@steveknight878]

My understanding - going back to the 1960s, so somewhat before all the sensor size wars, is that if you put a lens on a large format camera and take a photo, then - without changing anything else - put it on a smaller format camera and take a photo, then compare the area of the large format camera that is covered by the smaller sensor, they will be the same in terms of angle of view and depth of view. If you change your viewpoint with respect to the subject, then the angle of view will change. If you change the focal length of your lens, then you will not change the relative sizes of foreground and background objects - only changing your position will do that. If you take a photo with a 50mm lens, and enlarge the centre area then you will get the same effects as if you had taken the same photo with a longer focal length lens that contained the same part (area) of the scene. So for instance if you take a photo of a No Entry road sign with a 50mm lens, and then with a 500mm lens (assuming you are far enough back that the sign is contained withing the frame of the photo) from the same position, and printed both images with the sign the same size, then (grain/pixels aside) they, and their backgrounds, will look the same. Is any of that incorrect?

[@ThomasEisl.Photography]

Hey Steve - your statements are correct! There is only one - practically irrelevant detail - the more you have to enlarge an image, the less depth of field you will get, as the "blur" will be more visible. However, the effect is almost negligible in practice.

[@bpcs63]

Well! There you go. But the pixel peepers will continue to justify themselves. They all need to be challenged to pick the formats used to make a 20" print. A major reason the bigger formats are preferred is that nobody born into using digital, as opposed to film , knows how to use flash or control light or expose properly... the slide film intolerance to exposure errors or the slowness of film speeds never taught them. So the greater latitude to errors, and ridiculous high ISO usage, forces them to rely on larger sensors. Thank you again on an excellent video!

[@ThomasEisl.Photography]

Agree completely! Thank you for your kind words!

[@patrickhopkinson1851]

Brilliant that you mention large format. Everything else is a compromise.

[@ThomasEisl.Photography]

Very true! Large format is real photography.

[@josgeusens4637]

I was wondering what I miss in the following comparison ... Let's compare a Full Frame sensor and a MFT sensor. Both have the same sensitivity. We use them side by side under the exact same lighting conditions and at the same shutter speed. The f-number of both lenses are f/4.0. To get the same field of view, the FF camera uses 50 mm. The MFT therefore uses a 25 mm. Using the same shutter speed, f-stop and ISO, both resulting photos will be perfectly exposed. I see the same histogram for both. That's surprising because the FF lens has a diameter of 50/4 = 12,5 mm while the MFT lens has a diameter of 25/4, which is 6,25 mm and thus letting only half the light through. I guess it must be the way I think about this, but what's wrong?

[@ThomasEisl.Photography]

What you are missing is that f/4 tells you how much light a lens gathers per area, not in total. In total, the 35mm lens collects more light, but it spreads it out over a wider area. So even if you put it in front of a different sensor format, you will get the same amount of light per surface area, and not more or less. That's why the f number is such a useful metric. Hope this helps!

[@josgeusens4637]

@@ThomasEisl.Photography I now wonder how I missed that simple fact... Of course a 35 mm is closer to the sensor than a 70 mm and the spreading will be less. Thanks for clearing my brain, Thomas.

[@ThomasEisl.Photography]

@josgeusens4637 most welcome! Also, the image circle of a "full frame" lens is larger than that of an MFT lens, so it gathers more light, and spreads it over a wider surface. But I think I already wrote that. Best wishes, Thomas Thanks for engaging!

[@wayneholmes637]

I have a Nikon d5300, d7200, Canon EOS M, 6dii and a 7dii. However some of my best pictures were made with the small old EOS M with its kit lens in monochrome and processed with Silver Efex.

[@ThomasEisl.Photography]

Yes - it is not really about the gear, but how much effort we put into the process and our art!

[@pedrorrodriguez1]

I've been confused by your statement that different sensor looks can't be matched. Not necessarily disputing it, just curious. Resolution can be matched (on digital cameras), and dynamic range is not as relevant depending on the scene. The angle of view of the lens can be matched between systems. What remains is depth of field, which can be matched quite well at least between medium format and full frame. However, most comparisons I see online are taken focusing on a very close subject, and blurring the background to oblivion. The most striking difference between medium format and the rest (at least to my eyes) seems to be that it is possible to achieve a shallower depth of field, with a wider angle of view at medium distances, though this observation is only anecdotal, and i don't know if that can be matched between systems as well.

[@ThomasEisl.Photography]

Well, the statement is indeed very theoretical - as you can achieve a very similar if not almost identical look. But if you want to match everything that constitutes an image - including colors, noise, sharpness and so on, it is as good as impossible. Why did I make this statement - to underline that every system has its own unique look and feel.

[@pedrorrodriguez1]

@@ThomasEisl.Photography when it comes to noise, resolution and colors you're right, of course. Until proven otherwise, I remain unconvinced about depth of field equivalence between systems throughout the distance scale. I'm able to achieve quite shallow depth of field with my m43 cameras close up, but at medium distances, everything quickly comes into focus. Not sure if that is the same for other sensor sizes at "equivalent" apertures

[@ThomasEisl.Photography]

@pedrorrodriguez1 Yes, reading DoF scales you are completely right. They are only applicable to the format the lens was originally designed for and even then they are also subjective / dependant on the magnification of the final photograph.

[@pedrorrodriguez1]

@@ThomasEisl.Photography not sure I made my point clearly. Do you know if depth of field increases towards infinity at a faster rate in smaller sensors at equivalent focal length and depth of field than on larger sensors?

[@ThomasEisl.Photography]

@pedrorrodriguez1 If the exact same criteria are used, no.

[@washingtonradio]

Interesting that with quality gear, it's hard to distinguish images on different sensor sizes from each other for almost all practical purposes. Thus, which system is best is really heavily influenced by the photographer's use case and preferences as well as what is commercially available.

[@ThomasEisl.Photography]

Agreed!

[@franciscov.9644]

Hi Thomas, despite having a curious mind and having studied some science and liking photography since I was a kid, there is one thing I don't understand: How can it be that a 50mm at 1.4, will gather the same light as a 100mm at 1.4 or a 28mm at 1.4, since actually the diameter of the apertures differ ( 35.71, 71.42 and 20)?

[@ThomasEisl.Photography]

Hey Francisco, that is a bit tricky. Here is the thing - the 50 and the 100 focus the light to the same sized sensor. The 50, however, takes in light from a wider angle of view. The physical opening to gather enough light for the surface can therefore be smaller. The 100 is gathering light from a smaller angle of view. To get the same amount of light to the same sized sensor on the back-end, you need a bigger opening. Hope this helped!

[@professionalpotato4764]

Regarding equivalent image quality, I wouldn't say there were indistinguishable. The OM-1 was clearly less sharp in every way. Though it probably doesn't matter in a practical sense. We can simply refer to lp/mm or lw/ph. Given the same print size, the issue smaller formats will face is the lack of resolution. Even the same 24mp on a crop sensor will not print as large as a 24mp on a FF or MF for example. Simply because a lens for smaller format has to resolve far sharper images than larger formats in order to reach the same lw/ph. Or another way of looking at is is we have to enlarge a smaller image circle to match a larger image circle and all the lens imperfections will be magnified. And this was seen in your print comparison. However, I would like to raise... not a flaw but perhaps an opinion about the test photo. There was insufficient objects to compare detail apart from the screw on the lens. A scene of more fine details would display the differences even further. The DPReview image comparison tool is a good way to see it although it is still severely flawed due to their use of native lenses and not a standard lens across all brands. In my opinion, image quality testing should be tested not with native lenses but 1 single adapted lens.

[@ThomasEisl.Photography]

So this is probably a "lost in translation" thing - practically (direct translation) in German means in this context "as good as". The 645Z is sharper and more detailed, as you've said! Also, completely agree regarding bigger is better - it just is the way it is! Regarding the test photo - yes, it was not meant to be a precise comparison, but just a way to illustrate how small the difference is for practical applications. Also, regarding the dpreview scene - it is useful, but I would not buy a camera based on that alone. As you said, there are issues with the lenses used and so on and so forth - although I would not use the same lens for every system I test. Thanks for contributing and the constructive criticism.

[@ppzart]

I have to disagree to use a single lens for different formats - the results would be purely theoretical. As the working photographer in this video explains - 18*13cm big format will be king in theory, but for practice it is only relevant, if the system can deliver. The pro lenses in m43 are sufficient to deliver enough lp/mm. They profit of higher grade elements due to smaller size and less material use. Then every scenario will differ - you will need to take assumptions that will influence the outcome of your test - the same angle of view and dof are one thing, the dynamic or tele-compression of the subject, shooting distance, light settings due to distance and different base ISO - all will behave differently. So what a photographer needs to know, is not what a sensor could deliver, but if the system does deliver. Comparisons on KZbin without a practical benchmark in a sufficient product - like the double page - are only a marketing tool, as you will admit.

[@professionalpotato4764]

@@ThomasEisl.Photography I love your straightforward content and the neutral stance in your videos, unlike the other full frame "salesman". Keep it up :)

[@torb-no]

Great video! I agree about choosing camera. When people ask me about which camera to get I always say buy camera like you buy a guitar, get the one that feels nice in the hand and makes you want to use it. As for asbolute image quality (not that it matters, I’m just curious). I wonder if PhaseOne’s digital medium format cameras (which habe sensor sizes of traditional medium format) might be able to compete with analog large format (in some aspects like resolving details, not the look obviously).

[@ThomasEisl.Photography]

Thank you! Does a PhaseOne resolve an absolutely staggering amount of detail - yes it does! But: Estimates assume that a 4x5 large format resolves 300 MP, that is above what the phase one can do. The size difference is just absolutely incredible. An 8x10 is around 1.200 MP (!) In terms of ease of use - the Phase One is for sure the winner hehe

[@baptistepayendessinphoto]

Nice explanations, thanks ! (But i think you’re wrong on one statement : If I shoot with a 25mm at f/4 on a medium format, and then I crop the image to match the m43rd field of view with a 25mm at f/4, I can fake m43rd with a digital medium format. )

[@ThomasEisl.Photography]

So here is the thing, you can fake it in a way that it looks the same, however, the enlargement will be different (MFT being smaller) and therefore the DOF will be a bit different, esp. the near far distribution. It might look almost the same, but it won't be exactly the same. It is quite technical, and I don't see huge impact on practical photography, but I still found that interesting to mention. Fun fact: did you know that because of this effect, 50mm 1.4 focused at 5m will have less DOF on a smaller sensor? Yes, the crop will be different, but (!) It will actually have less DOF (although minimal) Thanks for asking, also thanks for the kind words!

[@baptistepayendessinphoto]

@@ThomasEisl.Photography I don't understand how the part of à MF image corresponding to a M43rd size couldn't be the same as an image generated by a M43rd sensor at the same place, behind the same lens. If you use "equivalent" focal length and aperture, and ISO I totally agree with you. But I don't understand in which way the enlargement differs between a crop sensor and a cropped image taken with the same lens and showing the same field of view.

[@okaro6595]

It important to make difference between digital crop and cropping a print. When you crop digitally the result has no inherent size. If you crop a print then the result has a size that is smaller. If you crop digitally it is no different from what a crop sensor produces (if one ignores the pixel count). Cropping digitally increases imperfections so noise increases and the depth of field decreases.

[@sdrtcacgnrjrc]

I probably should watch this again first, but I'll ask anyways. Let's say we have an M43 camera & a full-frame (FF) one. Prime lens @ 50mm on the FF, and 25mm (50mm equivalent) on the M43. Now, I'm still not clear: will e.g. F4.0 give the same amount of light on a small and a large sensor? Let's say that right now, my M43 camera needs a shutter speed of 200 with F4 aperture (@ 100 iso). Will the full-frame camera also require the same shutter speed (with other settings the same)?

[@sdrtcacgnrjrc]

I understand that the depth of field will be different

[@ThomasEisl.Photography]

Hey Tom! 1) Yes, you will have the same exposure settings (f number, ISO, SSpeed) on both cameras and get the exact same image in terms of exposure! 2) The bigger sensor collects more light in total - as it is bigger - but, the smaller sensor will get the same light per surface area! Therefore, same exposure settings. It is like when shooting film - if you put an ISO 100 film in a camera, it will be always ISO 100, no matter how big the camera / film sheet is. Hope this helped!

[@okaro6595]

It gives you same intensity of light but the full frame gets almost 4 times the amount of water. Think of you collect rain with different vessels. Each vessel gets the same depth of water but the large ones get a bigger amount of water. Sure the exposure will not depend on the sensor size. However, if you want similar image you should use f/8 and ISO 400 on full frame. Then the depth of field and noise would be same.

[@TL-xw6fh]

@@okaro6595 It lets in 4 times more light because the sensor area is 4 times more than MFT! Therefore, on a per sq mm area, the lumens is the same. Hope you understand this simple physics.

[@sdrtcacgnrjrc]

Thanks all, just wanted to get that put of the way. I still have to watch the video again cause there's concepts there that I never really came to grips with

[@griffith500tvr]

You mention image quality of large format film cameras, is it not true that the result I usually see of such a system has been scanned to make a digital image which I can view on my computer, if the scanner is not of the highest technical specifications then I will never see that difference in image quality. Am I thinking about this wrong? Obviously if you develop a large format film image in the dark room I expect to see the a large difference in quality.

[@ThomasEisl.Photography]

Thank you for bringing this up! This is a very interesting question - the resolution is only one part of the equation. The "problem" with non-large format cameras is that you have to enlarge the captured image quite a bit and therefore you are magnifying "lens defects" as well. So even if you scan a large format negative with a moderate scanner, the IQ will still be superb. Remember old Kodak box cameras - even those were able to produce respectable images as the negative format was just so big that there was not a lot of enlargement needed. There is a lot to scanning, as you've already hinted, but this is a good rule of thumb. In my next video on diffraction, the effect of enlarging "lens defects" will also be included, with a surprising twist, however.

[@kouroshlife]

Focal length can not be ignored in depth of field. Keep aperture, focus distance, and magnification the same. If you then use a higher focal length, you have shallower depth. You cannot eliminate the 4th variable. Sure, focal length and f-stop are related by opening diameter or aperture. But whichever variable you rewrite, you will still end up with 4 variables that impact depth of field and not 3.

[@ThomasEisl.Photography]

Interestingly, focal length impacts almost exclusively the near-far distribution of DOF - I know it sounds very strange at first. May I suggest the following link - they explain that in even more detail: www.cambridgeincolour.com/tutorials/depth-of-field.htm

[@kouroshlife]

@@ThomasEisl.Photography I don't believe your article is accurate because you assume when you go to a higher focal length then you need to proportionally adjust your distance (i.e., you are forcing constant angle of view). So you are implicitly eliminating one of the 4 variables that influence depth of field. And that leads you to draw an incorrect conclusion. Also, the variables have a different effect on depth. Distance to object has a squared effect ... you get 2x closer and you reduce depth by 4x. F-stop has a linear effect ... f/16 has 2x f/8. Magnification has linear inverse effect where 2x higher leads to 2x lower depth. Focal length has inverse squared effect in this version of 4 variables ... 2x gives you 4x reduction in depth. So saying it has a negligible effect is very incorrect. Here is one expression for depth-of-field being proportional to (f-stop number) * (distance to subject)^2 / (magnification of output) * (focal length)^2 ... you can rewrite that with other variables given (f-stop-number) = (focal length) / (actual opening diameter size of lens). For example, you can write it as proportional to (distance to subject)^2 / (magnification of output) * (actual opening diameter size of lens) * (focal length). Notice that the focal length is still there. You can also rewrite this as proportioal to (distance to object)^2 / (actual opening diameter size of lens)^2 * (magnification of output) * (f-stop number) ... it seems like you got rid of focal length but notice that you now have the f-stop-number showing up in addition to actual diameter (i.e., it is effectively bringing back focal length and it is not focal length independent). Hope this helps you appreciate the fact that your simplifications lead to incorrect conclusions. And happy to engage offline if you like. Best, Kourosh

[@ThomasEisl.Photography]

Thanks for taking the time to add that! Here is one of the best articles + math on the topic I'm aware of: www.normankoren.com/Tutorials/MTF6.html

[@kouroshlife]

@@ThomasEisl.Photography please pay attention to the article and table you cite above. That table shows that distance to subject is increased proportionally as you use higher focal length! For that case, it shows that IF you double the distance to subject as you double focal length while keeping f-stop constant, then the width of the depth of field does not change. That is correct. BUT, you are not expressing that assumption here. Say I am 3m away from my subject , use a 50mm at f/2 and then use a 100mm at f/2 from same distance. My depth will be radically different! It will be 4x narrower! To keep f-stop the same, the opening aperture grows by 2x. The other 2x in that 4x narrower depth comes from 2x longer focal length. Please plug above scenario into any dof calculator and understand and appreciate it. Sure my angle of view changes above, but nothing in your discussion talks about keeping the same angle of view as you change focal length on the same sensor size by moving further away from your subject. You just make a generic statement that depth is only impacted by three things (aperture, distance from subject, magnification) and not focal length ... and that statement is simply false. IF you added that you are assuming that you always have to keep angle of view the same on a given camera as you change focal length (a big assumption) then the observation that all things being kept equal (magnification and f-stop in this case; aperture needs to change to keep f-stop the same ... if you kept aperture the same even this statement would not hold) leads to same depth is accurate. BUT, you are NOT mentioning that HUGE assumption which is neutering the focal length impact thru changing distance to subject. Look at my expressions ... they indeed show the same IF you act according to your assumption. BUT how many photographers do you know that want a tighter shot, hence switch to a longer lens from same distance to subject ... do you want to tell them keeping distance, aperture opening (implies f-stop being 2 stops different if you 2x focal length) and magnification the same leads to same depth under that condition??? It will not ... even going from say f/2 to f/4 (2 full stops) will still lead to 1/2 the depth of field. If you were to keep f-stop the same (double opening aperture), the depth will reduce to 1/4 of what it was. You have seen one rule of thumb and seem to ignore a huge assumption on that rule of thumb, repeating it with confidence without repeating the huge assumption that allows for that rule of thumb. The expressions I shared allow you to derive ALL such cases without taking one specific case and stating it as if it applies in general. Again, happy to clarify offline if you like. Best, Kourosh

[@joestrahl6980]

Thanks for this video. I will try to arrange for a coffee even though I dislike paypal. At about 16 minutes you speak of using a double page spread as what should be used to compare "image quality" between camera systems. While I understand what a double page spread is (an image reproduced on opposite pages in a magazine as one picture) the absolute size in mm x mm is not obvious nor did you provide the dimensions in your video . Clearly the dimensions of a double page spread will depend on the format (external height and width) of the magazine. You could have a double page spread that was smaller than an A4 or a double page spread that was much larger than an A3 etc. Could you explain? Instead of using this *print* "standard" of double page spread as the basis for comparison ... since the overwhelming majority of photographs are now viewed using digital devices - on an iPhone or on a laptop - would it not make more sense to compare images on a 13 inch or 15 inch 1920×1080 screen? Or max it out with 4K resolution on say a 27 inch monitor? While these devices generally have a 16:9 proportion width to height and most camera sensors are 3:2 or 4:3 it is still fair to say that as a thought experiment a 1920x1080 is about 2 million pixels and a 4K is about 8 million. With my Panasonic Lumix G80 (called G85 or G81 in some places) at 16 megapixels using a 4:3 format and thus "the whole sensor area"..that sounds like a significant overkill in terms of data for a typical laptop screen or Ipad or 6" smartphone...and just a bit of overkill for a 4k monitor. Do you agree? Now there are other use cases, an image might be printed on something larger than A0 say....but since that is, in the grand scheme among all photographs taken including smartphones, not so common.... it just does not feel like a suitable case for comparison (?).

[@ThomasEisl.Photography]

Hello Joe! I used a total format of A3 for this comparison. I agree that digital devices require even less resolution. And I also agree that taking A0 as a reference is not necessary as viewing distance and general use cases make this format a bit "too large" in my view. Thanks for contributing!

[@borderlands6606]

There is a minimum size that a camera can be to have full control layout, and fit the human hand. Manufacturers could make all controls touch screen and shrink the body to the detriment of overall functionality, or in the case of professional models, add more programmable buttons and a heavier chassis, to the disadvantage of size. Either way, there are practical limits on camera size that are not directly related to sensor size. In the early days of "crop sensor" cameras, manufacturers exploited the natural advantages offered by micro four thirds and aps-c sensors to create a smaller camera. As time moved on those manufacturers offered professional cameras at the same time full frame makers were shrinking their products. This resulted in cameras having only a passing relationship to sensor size (Olympus E-M1X vs Sony A-series). This has resulted in sensor formats becoming associated with specific disciplines, m43 for wildlife and video (smaller lenses, better stabilisation). The market place speaks, however unwisely, and momentum is towards a universal "full frame" format, at least for stills.

[@ThomasEisl.Photography]

Agree - there is a minimum size requirement for a camera body - hands don't really shrink haha Regarding the universal full frame - there is a big "hype", and manufacturers who - coincidentally - make FF cameras, really push the format and try to sell it as the end all do all. I do not think that this move will be successful. Ppl already start to realize that FF mirrorless is just as big as FF DSLR, and they are again in search of more compact solutions. This always means smaller sensors and cameras like the OM-1, G9,... show the capabilities of the platform. Thank you for your very thoughtful, relevant comment!

[@imagenatura]

Interesting points you've made... You talked a lot about depth of field, which is not any real standard of anything. You should have talked about "blur circles" as they are mathematical and can be measured. Two cameras producing images with equivalent field of views and blur circles CAN produce exactly the same images, in theory. However, those cameras and lenses do not exist, but are possible. I suggest you look at an article written by Steve Yedlin about this subject on his personal website. Thank you for putting in the effort to make a KZbin video and tackling a subject that is relatively hard.

[@ThomasEisl.Photography]

Thank you very much for taking the time and bringing this up! So, after having studied the article, I think we are on the same page here: You can definitely match the blur circles (the "real thing", but rarely used in practice, so that is why I mentioned the flawed DOF-thing) as demonstrated in the article, but from what I know focal length would indeed impact the near-far distribution, leading to a slightly different (although probably indistinguishable) result in the final image. (also see e.g. www.cambridgeincolour.com/tutorials/depth-of-field.htm) Would love to hear your opinion on that!

[@LonStar3000]

Does a light meter distinguish F stop on frame size? Heck no! At least you know this and only one other that I know of does know this. They always change the equivalent F stop from a FF to 2X on a M43!

[@ThomasEisl.Photography]

I know, I know - and it is really misleading. People are drawing the wrong conclusions and making uninformed buying decisions because of this. Thanks for the comment!

[@elho001]

In the summary, you forgot available lens choice for ones intented purpose as an important factor in selecting a system. Saying that the light gathering/collecting ability of a lens is characterized by the f-stop is ambiguos, if not wrong. As correctly explained, the f-stop the geometric aspect of how much light the effective aperture allows to pass through the lens onto the sensor. However, how much light actually reaches the sensor that is not lost to practical imperfections of the optical system is characterized by the T-stop value. Those cheap f/0.95 lenses get you the bokeh of f/0.95, but an expensive modern f/1.2 of same focal rength makes more photons end up on the sensor instead of being lost within the lens and so actually gather more light and be the better choice if low light performance was the only criteria.

[@ThomasEisl.Photography]

I think you missed the point of this video - consider rewatching and stay tuned for more videos on this topic - lenses will be a separate video as I've recently talked with Peter Karbe, chief optical eng. at Leica about that and I will share many insights also regarding the 0.95 topic. I'm sure you'll be quite surprised. There are many fundamental misconceptions in photography, and that is one of them. Cheers :-)

[@elho001]

I got the point of speaking about sensor size, where f/1.4 is f/1.4 no matter the sensor. But a viewer that does not know better may be misled by the ambiguos light gathering bit to draw wrong conclusions. So I wanted to point that out to those along with an example. But yes, I really appreciate you doing videos that dig deep and look forward to future ones! 👍

[@ThomasEisl.Photography]

Ahhh, sorry about that - it seems it was me who completely misunderstood you! Sorry for that, I completely missed that! Thanks for engaging and have a great week!

[@elho001]

@@ThomasEisl.Photography Hehe, no worries. Have a nice week as well!

[@Superz3ro]

Some of the best most iconic images in our history, were taken with cameras that would be considered inferior today… Realistically, those cameras are as relevant as any currently produced, be it an action camera, smartphone, or even a mirrorless interchangeable lens camera… 🤔

[@ThomasEisl.Photography]

Completely agree - thanks for watching so many videos and taking the time to contribute in the comment section!

[@alexandrosel1131]

From a technical analysis, what was said is correct. But there is one detail that is missing and it has to do with the aesthetic effect of each format. A full frame sensor with a 50mm lens gives the same field of view as a 25mm lens on a 4/3 sensor. The 50mm lens however gives different proportions of the objects compared to the 25mm: the background in the 50mm appears larger and closer to the main subject compared to the 25mm. These proportions are also the reason that the larger a format, the more "compressed" the objects look for the same field of view, as lenses with more millimeters are required for the same field of view. This is why I never use a sensor smaller than full frame: the proportions between near objects and far objects are dispresed a lot in small formats.

[@rudyhulsmans7443]

Interesting. I understand what you are saying. Just would like to know why you prefer the compressed look over the dispersed look? Isn't compressed = flat? Would love to hear your opinion on this!

[@alexandrosel1131]

It's the same reason why we old photographers in the past preferred as large a format as possible: all the elements that made up the subject were present without looking small in the background and without distortion. Highlighting the main subject was done with the depth of field which is extremely shallow in 180-240mm lenses which were normal in large formats. This is why photos from large format cameras of the past look "dominant and imposing". Of course today we live in the age of speed and convenience where even a full frame seems "heavy". These concessions to quality will eventually kill the arts sooner or later.

[@tuhisdraws]

Is this true? Doesn’t the compression come from the distance between the photographer and the target? So if you’re standing on the same spot and taking photos with a full frame camera using say a 24mm and a 50mm lenses but then crop the photo taken with the 24mm lens to match the field of view of the 50mm lens, isn’t the compression in both images the same? Nothing in the scene is different and your point of view is the same, so why would the lens affect the compression? And this is a genuine question because I’m trying to understand how this works, not trying to provoke anyone into a heated debate 😃 (Feels like this has to be stated since this is KZbin and we’re chatting in the comment section of a video about equivalence 😂)

[@ThomasEisl.Photography]

​@@tuhisdraws You are correct - and this is actually an easy-to-mix-up issue, I'm glad Alexandros brought it up, I did not address it in the video. Here is the thing: As long as you stand in the exact same spot you will always get the same perspective. So the focal length does essentially change the field of view - in this case, it makes the field of view "equivalent" (I said it!) to get the same "crop". The images will have the exact same amount of background/foreground regardless of sensor format. You can test that on this neat little site: dofsimulator.net/en/

[@borderlands6606]

@@tuhisdraws It is counterintuitive because one of the effects of focal length is to change the apparent (but not actual) relationship between objects in a scene. It is the reason why a full moon rising over a house appears much larger than the same moon higher in the sky.

[@gustenisfeldt6976]

I don't think you explain why 'you cannot match looks between sensor sizes'. Given the same entrance pupil diameter and field of view, ideal optical systems should produce the same image. Aside from differences in sensor resolution, signal to noise ratio, etc, there would be no difference. Now in the real world, ideal optical systems do not exist, but it's much easier to design a lens with a smaller aperture to focal length ratio to have low amounts of aberrations. To create the same image with higher quality is therefore easier optically speaking with a larger sensor format. At smaller apertures, where well corrected lenses are diffraction limited however, I would argue that it is impossible to tell the sensor size given the same resolution and noise level. As a more direct example, a FF camera with an 50mm f2 lens will create very similar images to a m43 camera with a 25mm f1 lens, in terms of FoV and DoF, but the f1 lens likely has far more aberrations wide open than the f2 lens, so the quality of the FF images would be significantly higher, assuming similar 'quality' optics. When stopping down to probably something like f8 and f4 those differences will diminish.

[@ThomasEisl.Photography]

Thank you very much for the comment! The main reason why it is impossible to match two different formats exactly is the relativity of DOF - if you enlarge something bigger, you will get less DOF as the defects are more visible. The second, much smaller reason is the near-far distribution which depends on focal length. Regarding your last point - yes, the lens has to be optimized for the system! Thank you again!

[@Tbonyandsteak]

Yeah it is funny, how many that thinks how this is, but never actually really looked into it. Light is somelike how you calculate magnetism flux. Area flux and flux density. Area flux is the total flux available, flux density are the flux at mm^2 of the total flux. Same with light if you use the same lens at different formats. The lens produce a EV=total light x exposure time. If the different sensor format have the same pixel density they all reiceive the same light density. no matter the size of the sensors. If not NOW it is gonna get tricky.

[@ThomasEisl.Photography]

Agreed!

[@meta4101]

Conclusion ... forget about equivalence -- just get what feels best. I cannot concur although I would agree that there is a hidden truth underlying that statement -- some--perhaps many--photographers obsess on the specs of their gear rather than the artistry of their images. But throwing away equivalence entirely is taking it a bit too far in my opinion. You can certainly match the look -- field of view, subject isolation and noise level -- of a smaller sensor by cropping the image from a larger sensor or by via equivalence. The standard equivalence formula is valid when trying to match angle of view, light gathering and subject isolation of different formats and to me is far preferable to searching my feelings. For example, my16-50 f2.8 APS-C sensor has indistinguishable rendition to my 24-70 FF at f4 in terms of angle of view, subject isolation and light gathering of I can crop my 50mm lens' image to achieve 75mm aps-c equivalence or 100mm mft equivalence. The larger sensor is, of course, superior in terms of dynamic range and resolution (given similar sensor technologies). Interestingly, equivalent MFT lenses are about the same size and weight as their FF counterparts -- there is no free lunch in the world of optics. To balance things out--I'll make one final comment. I've never shot MFT, but I did shoot APS-C for years. My FF makes life far simpler for the kind of photography I do and allows the execution to be closer to my artistic vision with far fewer contortions. That said, sensor format and equipment, in general, has never been a unsurmountable limitation (for me personally). The vision of the photographer is the primary driver of superb images; the specs of the equipment are a distant number two.

[@ThomasEisl.Photography]

Absolutely agreed - there is no free lunch in the world of optics!

[@HokKan]

Sensor comparisons are often made too confusing. All the equivalency talk is what makes it confusing. The difference between cropped sensor and full sensor is very simple. The only difference is that the image is cropped on the cropped sensor. Compare a photo of a 50mm lens on a FF sensor and then take the same photo using the same lens, but adapted to a M43 sensor. The only difference you will find is that the image is cropped. Everything else will be the same.

[@ThomasEisl.Photography]

Yes, if we want to be super nitpicky, the image of the smaller sensor in your example will actually have less DOF at the same focusing distance. But practically, it is like you have said! Thanks !

[@HokKan]

@@ThomasEisl.Photography why is that? (less DOF)

[@jonasweiss5817]

Topaz Sharpen!

[@ThomasEisl.Photography]

Thanks for the recommendation!

[@elke1317]

Ich würde mir ja schon wünschen, den Inhalt auch auf deutsch hören oder lesen zu können. Dein Englisch ist zwar bestens zu verstehen, mein Englisch ausreichend für Vieles, aber wenn es so speziell wird, muss ich irgendwann passen. Schade, denn ich bin sicher, es würde sich lohnen, deine Ausführungen hundertprozentig zu verstehen.

[@ThomasEisl.Photography]

Vielen Dank Elke - ich kann Dir auf jeden Fall ein Einzelgespräch anbieten, in dem wir natürlich alles auf Deutsch besprechen könnten. Danke für dein Feedback und dass du trotz der Sprache meine Videos angesehen hast. LG Thomas 📸

[@rogermuggleton8127]

I wonder why people try to make these comparisons? Is it to justify their choice of equipment, maybe they are striving for the best possible results? While I am as guilty as anyone else when it comes to equipment, it sobers me to think about how others see my photos. First, most people who see my pictures are not photography enthusiasts or professionals. So they judge the pictures differently. A local professional publishes some of his photos of local scenes with saturation, contrast and colour 'tuned up to maximum'. I may wince at them, but the viewers love them. Secondly, most people see my photos online, usually on a phone. About 60mm wide. From about 40cm away. Their phone screen has less pixels across it than my original photos! A smaller size than the standard 6 x 4 inch prints we got from the chemist 50 years ago. I've just looked at some photos I took in 2001 on a 2 (Two) MP camera. Even at A4 size on my screen they look fine.

[@ThomasEisl.Photography]

Completely agree - thanks for sharing that!

[@MeAMuse]

People try to justify it to help people make better decisions. I shoot full frame, APSC, 1inch and smartphone (I also used to shoot M4/3 but got rid of that system because it was too close to APSC, and when I am portable now I go to 1 inch sensor). Realistically the system I take out depends on what compromises I want to make. Do I want portability or performance and quality. It is really that simple. A phone has a crop factor of 3 compared to a phone? Do you notice better quality? Or that it is easier to make a shot with a bigger sensor / system? In the end system choice does matter… and it is up to the individual to decide what system, or systems work best for them.

[@elho001]

The majority of people enjoys fast food and is unable to distinguish or aprreciate the difference quality igredients make. Also, an excellent cook could well take low quality ingredients as a starting point and thanks to his skills create a meal the majority of his customers would be happy with. Yet, no one would suggest him to do so, nor wonders nor questions why he would seek the best ingredients and why he dares to use quality cooking gear. And would that cook be advised to go by what the majority thinks about his food, or what the minority of connisseurs and qualified critics do? When it comes to the bare technical qualiity aspect of ones photos as a hobbyist, there is exactly one person on earth that matters as a viewer, and that is oneself. If one is a pixel peeper and perfectionist, who would either drool over the high image quality and level of detail to rediscover or only ever be reminded of the poor image quality when looking at his work, then one of course strives for high enough image quality to make himself happy with the result. Pretty logical.

[@rogermuggleton8127]

@@elho001 I suppose if a hobbyist spends a fortune on gear, they are obliged to justify their expense some way. So the usual thing is to judge the image quality by some unmeasurable, undefinable parameter, which justifies the inability to find any effective difference in objective tests. While I don't dispute that technology is improving in some ways, particularly the speed and accuracy of autofocus tracking on moving subjects, the end results are not advancing. The photos are just the same as before. I'm minded this year to break the rules and investigate the settings we avoid, like very high ISO. The art of image making is much more than optical measurements. Look at the work of Degas, Turner, etc. No Canon skin tones, no natural colours, no accurate representations and you can see the brush strokes. Even the early 35mm photographers broke the mould made by earlier professionals. Ropey film, ropey lenses, but photos we still admire today.

[@klaustomasini]

👍

[@ThomasEisl.Photography]

Thanks!

[@gregsullivan7408]

I'm not very happy with this presentation. Tony Northrup has done an truly excellent (IMHO) series on equivalency, including actual photos to back up his assertions. Suggestion: do another presentation, where you actually take some APS-C & medium format images, using "equivalent" lenses & apertures, and show us the results. Yes - it will be a contrived test, because you will have to choose lenses & settings that allow such "equivalence" - that's accepted & undersood. I can dig out his relevant videos if required. Note: "equivalent" apertures produce, in theory, the same DoF. This will of course result in different f-stop settings, and will then require a higher ISO on the larger sensor, because we want to keep the shutter speed identical.

[@gregsullivan7408]

Tony asserts: If two systems use the same quantity of light (intensity X area X time), to take photos with the same DoF & framing, and the sensor tech is about the same, the two photos will have very similar levels of noise. This is the most profound thing I have ever learnt in digital photography.

[@ThomasEisl.Photography]

Thanks for the feedback, interesting perspective.

[@gregsullivan7408]

@@ThomasEisl.Photography this is the most pertinent video from Tony Northrup: "Crop Factor with ISO & Aperture: How Sony, Olympus, Panasonic, Canon, Nikon & Fuji Cheat You"

[@ThomasEisl.Photography]

Well, that is not my line of thinking for various reasons. But thank you very much for sharing. Best, Thomas

[@gregsullivan7408]

​@@ThomasEisl.PhotographyWell, Tony backed up his assertions with photos. I'd be interested in why you don't agree, if you ever have the time. Thanks for your time, in any case.

[@LarryFasnacht]

I would LOVE to have you explain to me the difference between hyper focal and Infinity focus as shown in this video: kzbin.info/www/bejne/bYO8pZVsishprKs

[@ThomasEisl.Photography]

Hey Larry! I'll do that right away: 1) Infinity focus is actually the furthest distance any lens can be focused to - to a point that infinitely far away. That is pretty theoretical and in practice it just means: set the lens to this position if something is really really far away. 2) A great quote from cambridgeincolor: "The hyperfocal distance is defined as the focus distance which places the furthest edge of a depth of field at infinity." Practically it means if you stop down your lens, you will get more DOF. So you can actually focus the lens "in front of infinity" and the DOF will still extend to infinity. On an Olympus PRO lens you can see the scale on the lens barrel with corresponding f numbers. This indicates exactly that range. With MFT, I would not worry too much about that, as you have more DOF to work with and pretty easily achieve "hyperfocus". Hope this help - maybe I can make a video about that in the future!

[@klarion]

Well, you used the word "rhetorical" on youtube... And lost 90% of youtube audience in regards to understanding...

[@ThomasEisl.Photography]

😆