The Crop Factor Myth Explained

[@Davide_LP]

There's one major mistake, the compression is not due to the focal lenght but is due to the relative distance of the subject and the background from the sensor. So if you take a S35 camera with a 50mm lens and shoot a scene, and then, without moving anything, you shoot the same scene with a 16mm camera with a 25mm lens (same field of view) you will have the exact same compression of the background.

[@vagabondcaleb8915]

No. You don't. Because you either are going to get a different frame or different compression if you switch sensor size. If you were right, everyone would just shoot on smaller sensor sizes because there would be NO REASON to use bigger ones and smaller ones are vastly cheaper.

[@flyingfox2005]

@@vagabondcaleb8915 wrong. Sensor size has no effect on compression. Compression is purely a product of distance, camera to subject, subject to background. I quote DP Steve Yedlin: "Compression isn't actually an optical attribute in itself, but it's a word that's often thrown around while describing things in a confused way. Compression (in the sense that it's meant by filmmakers when discussing optical properties) is a combination of camera placement and angle-of-view -- it's just a combo of two other attributes. It means that your perspective is distant while your AoV is narrow. So, a shot that's 4 meters away from an actor on focal length x is much more compressed than (but the same image size as) a shot that's 1 meter away from the same actor on focal length that's one quarter of x. This is true no matter what the sensor size is. But, in trying to describe "the big format look," people often make a word-salad of focal length, AoV, and compression, like "you can get closer on a longer lens with the same AoV but it's more compressed." But that's just a self-contradictory jumble of words that doesn't really have any meaning. AoV and perspective are each properties that are not unique to one format size as opposed to another and are independent of one another (putting a certain lens on a camera doesn't force you to put that camera in a certain position in space -- a filmmaker is free to choose AoV and camera placement separately). And compression is nothing but how you combine AoV and camera postion when setting up a shot. If you use the same perspective (camera postion) and same AoV on two different sensor sizes, you'll have the same compression. Compression is not an attribute of the sensor size, but a description of how a filmmaker sets up a shot (like: do we back up with a narrower AoV or go closer with a wider one)."

[@ejmikk]

The reason is that you get more bokeh with a bigger sensor, that's not the same as lens compression. Lens compression does not exist. Check out Fstoppers' video explaining why.

[@Kakaellsen]

what are you talking. ​people use bigger sensor for tighter spaces, higherlight sensivity=better low light, better bokeh and many more reasons. he is right about his point. get your facts, this is not opinion talk.

[@flyingfox2005]

@@vagabondcaleb8915 compression is simply the product of distance. Camera to subject - subject to background. A 25mm lens on S16 has the identical compression as a 50mm lens on S35. The difference you will see (at the same ftstop) is depth of field. A 25mm lens on S16 has two stops less DOF than the 50mm on S35. Close the 50mm down two stops and the depth of field also matches. Read Steve Yedlin's articles on large format and matching blur across different formats.

[@colinjudge1261]

Bit of a swing and a miss on this one. I had to stop when you stated that the lens creates compression. Aside from the unique characteristics of each lens (sharpness, aberrations, etc), you will indeed get the exact same image if you use the crop factor principle. What's commonly forgotten though is that the crop factor applies not just to the focal length, but to the f-stop too. Framing up a head-shot on a Super 35 sensor with a 100mm lens at f/4 will give you the exact same frame, compression, DOF and distortion as staying in the same position and switching to a Super 16 sensor, with a 50mm lens at f/2. The only difference will be the exposure change due to the new f-stop, but this is also equaled out by the difference in sensitivity between the two sensors. All else being equal, a Super 35 sensor will show a similar amount of noise at, for example, ISO 3200, as a Super 16 will show at ISO 800, due to the smaller sensor having a worse signal to noise ratio given the smaller area on which it is registering light. I'm a fan of your channel, so don't take this as an attack, just a correction.

[@albionmerrick]

The lens does not "compress" the image. So-called compression is an effect of perspective. As you move away from something, it becomes relatively closer to the background. Making them seem closer. A 25mm with a 2x crop will have the same "compression" as a 50mm with no crop. It's the same perspective change that makes stars feel like they're inches apart, despite being lightyears apart.

[@deccawatt5741]

that's right, compression only depends on the distance to subject

[@Kliffot]

You're playing with words, the 25mm M4/3 of your example will have the same FoV of a 50mm FF but the rendering of the "compression" is absolutely not the same. You ll have to get 2x time closer to have the same rendering.

[@professionalpotato4764]

@@Kliffot Nope, it will have the exact same "compression". Read Petapixel "Is Lens Compression Fact or Fiction?" or Fstoppers "Lens Compression Doesn't Exist" Cropping a 25mm down to a 50mm fov will render the exact same fov AND background look. Just look at the image samples in the article. 16mm cropped to 145mm looks exactly the same.

[@flyingfox2005]

@@Kliffot 100% wrong. A 25mm lens on MFT has the same compression and perspective distortion as a 50mm lens on FF / 135. Compression and perspective distortion are both simply products of distance - nothing more. A 25mm f2 on MFT will have less blur than a 50mm f2 lens on FF / 135 ... despite having the same angle of view... but if you stop down the 50mm on FF / 135 down to f4 - the blur will match I suggest reading DP Steve Yedlin's articles on the myths of large format and how to match blur on different formats.

[@Kliffot]

@flyingfox2005 My bad by compression rendering I meant bokeh, background blur.

[@christoffer886]

Compression does not work like this. That's just a matter of distance between the camera and subject. You wouldn't use a 50mm as a "wide angle" close up on a s35mm being right in front of the subject, instead you might use a 35mm to get a wide close up. But if you put a 35mm on a 65mm you need to be much closer to the subject to get the same framing and therefore you get a more distorted wide effect. If you take a 50mm on a large format camera, match up the aperture a few stops for the same bokeh as a 35mm on a s35 sensor, frame it the same, they will look identical. The only two things that differs is that the resolution and glass distortions become much more visible the further out of the image circle you get; which leads to more lens artifacts visible on larger sensors, alternatively if the image goes into the extreme wide, the s35mm requires much wider lenses for the same effect and extreme wide angles usually are harder to get without heavy glass artifacts. The second part is covered in the video, but it's not as simple as this. You can match up much of the look between s35mm and large format, to a point. It's when you get into wider images that larger sensors show their prime. If you use a 24mm T1.4 for a really wide shot on s35mm with a shallow DOF, you get the same on a larger sensor with increased focal length around T2.8, but if you try to go wider on the s35mm you cannot retain the shallow DOF as wider lenses cannot be that fast. The larger sensor however can still go lower and retain a fast T-stop, resulting in a shallow DOF at lower focal lengths. So, you can get the same image on a s35mm sensor using a 35mm at T1.4 as a large format sensor with a 50mm lens stopped down. But as soon as you open that 50mm up you reach a DOF that isn't possible on the s35 sensor. The only way for that sensor to get a similar image is to go below T1.0 and that's a hell hole for glass clarity. This is the sole reason why larger sensors produce a shallower DOF, but the lenses do not compress or change any other aspects other than imperfections at the edge of the image circle.

[@vagabondcaleb8915]

Meanwhile, actual cinematographers opt for large format cameras simply as a flex. They could use 16mm and it would be much cheaper. But for SOME STRANGE REASON they use large format. WHAT A BUNCH OF STUPID PRO CINEMATOGRAPHERS WHO HAVE NO CLUE WHAT THEY ARE DOING. WE NEED TO REPLACE THESE FOOLS WITH GENIUS KZbin COMMENTORS. CHACHAHCAH

[@colinjudge1261]

Yes, thank you for bringing up the optical drop off around f/1.0. This is the limiting factor, and actually a reason why it becomes more helpful to use F-numbers rather than T-stops in this instance. Because effectively improving light gathering becomes more difficult, most f/0.95 lenses end up having a very similar T-stop to an f/1.2 lens. The USP of a Full Frame (photography) lens at f/1.2, is that an equivalent lens for a smaller sensor literally does not (and quite likely, cannot) exist. For APS-C sensors, the lens would need to be f/0.8. Inversely, people will sometimes look at things the other way around and say that a larger sensor camera cannot compete with smaller sensors for capturing deeper depths of field. But that ignores the fact that diffraction effects start to become visible at wider apertures on smaller sensors, so in practice f/22 on a Full Frame sensor is about as deep a depth of field as you can go while still achieving acuity.

[@JakobMaier]

I'm usually a big fan of your videos but i think you should delete and re-do this one. You got a few things wrong in the background compression section. The only real difference in image between sensor sizes is the amount of background blur, but this has nothing to do with the sensor; it's just that a 30mm lens at f1.4 generally has less background blur than a 50mm at 1.4 if used from the same distance, and you need a larger focal length with a bigger sensor to achieve the same FOV as with a smaller sensor. In theory, if you had a sensor with infinite resolution, you could shoot everything with say a 16mm lens and then crop in later to get every other focal length. The only thing that dictates background compression is the position of the camera.

[@NoSuRReNDeR001]

I AGREE its ARGIOUSLY erroneous

[@benjamin.kelley]

Fstoppers proved this!

[@jakphoto]

I have to sadly agree. this channel is otherwise methodically very accurate and balances creativity with logic but this is a big enough mistake to at least pin a comment about, if not re-edit and re-post the video.

[@JakobMaier]

@@jakphoto yup, sad that he doesn't seem to read/care about the comments

[@littleboy1425]

I want to clarify things up. Its a hard thing to say, but the compresion effect you were referring to as the result of the focal lenght of the lens used does, in fact, hypothetically, depends solely and only by the distance between the camera and the subject not precisely the focal lenght itself. the focal leght of the lense does only one job -- cropping the image in front of your eye into preferred sizes, in other words, control the field of view. let's say we are to shoot a shot opted for medium shot size, on a full frame camera (namely large format for cinimatography). you would be needing 50 mm focusing at 1.0m to get that shot size on this sensor size -- this shall be our control set. Then, we are to shoot this same shot on a camera w different sensor size, -- lets say super 35 having a crop factor of 1.5 compared to Full frame(LF) -- if we use this same 50mm lens focusing at the same 1.0 meter the image will come out to be 1.5 time croped, maybe it will become medium close up, so you will either need to move the camera backwards to, lets say, 2 meters to get the same opted medium shot, which creates a compression effect on the background and ,hence, has more feeling of dimensionality blabla , or -- more normal usual way -- change the lens in front of this super 35 camera into a 35mm which will give 50mm "FULL FRAME FEILD OF VIEW EQUIVALENT" and be able to shot at the same 1.0 meter focusing distance. Apart from this, talking about depth of feild (aka background seperation aka bokeh) is a different subject and is already mentioned correctly in the video. I am currently teaching cinematography in an art school using mainly the pocket 4k having micro 4/3, and was a photography using a normal full frame dslr. honestly, there is no actual difference form this crop factor "compression " and "dimensionality" kinds of things (apart from the size of the bokeh which no one who actually shoot cinematograph cares about much once its already shallow enough). You just need to know how to choose what lenses to used. The only concrete enough differece ive heard so far is about the difference in lens designs for each "focal lenght" which tends to make the wider (lower number) prone to more distorsions and spherical abberation and conversly, the longer(higher number) prone to chromatic abberation, but, honestly, in this era, should be all taken for granted.

[@BunnyChannel918]

hello! any cinematography book recommendations? 😢

[@Kliffot]

Seems there's confusion with words. Bokeh is compression. ( one aspect to be exact ) more bokeh = more compression

[@flyingfox2005]

@@Kliffot Bokeh is NOT compression. Bokeh is a product of depth of field - which is controlled by choice of focal length and fstop. Compression is purely a product of distance, camera to subject, subject to background. I quote DP Steve Yedlin: "Compression isn't actually an optical attribute in itself, but it's a word that's often thrown around while describing things in a confused way. Compression (in the sense that it's meant by filmmakers when discussing optical properties) is a combination of camera placement and angle-of-view -- it's just a combo of two other attributes. It means that your perspective is distant while your AoV is narrow. So, a shot that's 4 meters away from an actor on focal length x is much more compressed than (but the same image size as) a shot that's 1 meter away from the same actor on focal length that's one quarter of x. This is true no matter what the sensor size is. But, in trying to describe "the big format look," people often make a word-salad of focal length, AoV, and compression, like "you can get closer on a longer lens with the same AoV but it's more compressed." But that's just a self-contradictory jumble of words that doesn't really have any meaning. AoV and perspective are each properties that are not unique to one format size as opposed to another and are independent of one another (putting a certain lens on a camera doesn't force you to put that camera in a certain position in space -- a filmmaker is free to choose AoV and camera placement separately). And compression is nothing but how you combine AoV and camera postion when setting up a shot. If you use the same perspective (camera postion) and same AoV on two different sensor sizes, you'll have the same compression. Compression is not an attribute of the sensor size, but a description of how a filmmaker sets up a shot (like: do we back up with a narrower AoV or go closer with a wider one)."

[@littleboy1425]

@@Kliffot Yea, you might be correct. it does partially influence the size of bokeh balls but im sure not the depth of field?. Anyway, the word compression effect is so confusing as mr.flyingfox explained. There is no need to be that techically precise.

[@Kliffot]

@@flyingfox2005 yeah as I said confusion of words, I actually had bokeh in mind. Now you're mentionning the MF look, as I see it, the advantage is not having bad distortion when getting closer with longer lens while keeping a wider look ( + eventually extra bokeh fall of )

[@jinchoung]

yikes... you got the section on "compression" completely wrong. it is NOT a function of the focal length. it is a function of DISTANCE FROM CAMERA. in all the cinema books where they're showing you the differences in focal length on image compression, they're actually MOVING THE CAMERA in order to keep the subject the same size in the frame. THAT is what causes the difference in compression. so for example, if you take the typical example of shooting telephone poles receding into the horizon vanishing point - if you shoot that with a wide angle lens, the poles CLOSER to camera will look farther apart. but in that exact same shot, shot with the wide angle lens, if you zoom in on the telephone poles in the distance with a magnifying glass, their distance from each other looks COMPRESSED. those poles, at that distance, shot with a telephoto lens to fill a screen will have the exact same compression that was visible when shot with the wide angle lens... it would just fill the screen.

[@gony_kun]

I guess it depends on what’s the meaning of the word “function” here.

[@BunnyChannel918]

any book recommendation that explain this further?

[@flyingfox2005]

@@BunnyChannel918 I suggest reading DP Steve Yedlin's articles on the myths of large format and how to match blur on different formats.

[@jinchoung]

@@gony_kun it's not the cause of the difference. as i said, in a wide angle lens photo, if you look at something in the bg that's far away in the shot, it will have the compressed perspective that is attributed to a telephoto lens. all the telephoto lens does is makes something far away fill more of the frame. the perspective change is as a result of distance.

[@gony_kun]

@@jinchoung yeah, but now you’re using the word “cause”, which is different from “function”. If we’re nitpicking we might as well use wording that isn’t confusing. I think you meant “result” initially, instead of “function”. Though, of course in this context does it matter if compression is the result of distance? Isn’t a telephoto’s actual “function” to limit the field of view so that you get compression out of faraway subjects? Is it its function or kust something it does due to its characteristics?

[@SaxSpy]

please stop with the compression lie. its distance.

[@thermonuclearcollider4418]

2:07 "28 Days Later" was shot on Canon XL1S cameras: they were 1\3'' machines. 3:13 Sorry, but the standard everything is derived from is full frame. That's the "1x" format. As such, Super35 has a crop factor of approximately 1.5x (different sensors have a slightly different diagonal while with film it really depends on the amount of perforations and wether or not you're shooting open matte).

[@naruto5046]

after reading all these comments, it has reaffirmed my understanding that most people are still “spec & technical” guided rather than “creativity & feel” guided, which for me is more important in the field of cinematography.

[@SquirrelHybrid]

All someone needs to do is shoot with 2 different focal lengths from the same spot with matching depth of field (ie. 25mm @ f/2 vs 50mm @ f/4), and then crop to match. The compression, bokeh, and distortion should look pretty much identical if the optics are of similar quality, but the image fidelity is higher on the larger sensor. Optical distortion varies from one lens to another - if someone compared a highly-corrected wide-angle lens to a pancake lens of a slightly tighter focal length with a ton of barrel distortion and then cropped to match, then you might think the tighter lens has more of the wide-angle distortion look.

[@okaro6595]

No, it should be 25 mm f/2 (a typo?) . The ratio need to be the same. (Also i.e. = "that is", while e.g. = "for example")

[@SquirrelHybrid]

Corrected, thanks. 🙂

[@Tony__S]

If you have ever used a zoom lens you should immediately recognize that compression doesn't exist. Zooming in changes the focal length, yet zooming in expands the image the same as 'cropping in' on the sensor, same as zooming in in post. The one exception is that at a constant f-number, the zoom lens will make the background more out of focus as it zooms in. All lenses (outside of special machine vision lenses used in manufacturing) have the same perspective. Fish eye, 10mm, 1000mm, anamorphic - they just have different magnifications. Another way to convince yourself is to think of why objects don't look darker as they get further away. We know further away light sources dim by "one over the distance squared". Well all objects imaged by a lens also are rendered smaller by "one over the distance squared" - twice as far away and they appear half as tall, and half as wide, so one quarter as big, and so the light per area in the image never changes.

[@timschneider8139]

Just to be clear: isn‘t the 1x crop factor referring to 35 mm wind up film in photographic stills cameras? Which is apparently larger compared to the S35 sensor area. I think that debating about crop factors and sensor sizes in digital cinema technology first started when people used full frame lenses on their (digital) APS-C or mFT camera bodies - which in the first place were DSLRs. The so called „full frame image circle“ was - as far as I know - never a significant measurement size for cinema lenses. Although lenses for larger format film areas like 65 mm negative stock existed since the mid 1900s. There are of course 0.x crop factors which refer to sensor/film areas larger than „digital“ full frame or 35 mm celluloid stills film but I think the 1x crop always referred to what is called „full frame“ (nowadays).

[@timschneider8139]

Addendum for precisioning: the Alexa 35 is a digital imaging device with an S35 sensor. That in fact IS a crop sensor of about (roughly) 1.5x.

[@flyingfox2005]

Not true I've seen plenty of documents by lens makers (Leica) and even Panavision (when discussing lens choices for 65mm) that take S35 (3 or 4 perf motion picture film) as the baseline with 1x crop factor.

[@timschneider8139]

@@flyingfox2005 That’s interesting! Thank you. I just replied to one of your other comments 😉

[@flyingfox2005]

@@timschneider8139 the Alexa has a 1.5x only compared to the totally arbitrary "full frame" photography standard. Crop factors work from any format to any other. In cinematography S35 (3 or 4 perf) is considered the baseline... not so called "full frame".

[@flyingfox2005]

@@timschneider8139 the issue is really a battle between how things have worked in cinema for over 100 years (4 perf as the standard, but DPs knowing how to move between other formats) and photographers who post the Canon 5D now think that they have invented using different formats and that everything revolves around "full frame". Full frame in cinema goes back to the 50s when it was branded as VistaVision - and it ran the film horizontally through the camera, while a standard 35mm movie camera, rans it vertically. The two camera systems use the piece of film (with a width of 35mm) differently. The "standard" (simply the format that has been ubiquitous for over 100 years) is what is now called S35 - and so that is what most DPs view as the baseline. The term "full frame" was simply marketing to the prosumer photography market to differentiate between 8 perf and 4 perf film (FF and S35) to the prosumer market. The problems is too many people have taken the word "full" to mean complete and view it as the baseline, when it reality of course, it's just another format... with all the usually pros and cons. If you are comparing FF to S35 the of course you can use a crop factor of 1.5 if that makes it simpler... the issue come when people are comparing say S35 and MFT and insist on round tripping the calculation via the totally arbitrary FF format. All this does is introduce inaccuracy to the calculations. All that ever matters when comparing any two formats is their individual horizontal measurements.

[@absolutelyeverything]

FYI super 35 (1.5x crop factor) and full frame 35mm (1x crop) are different things 3:21

[@flyingfox2005]

In cinema S35 is the baseline and has been for 100 years. It is a KZbin myth that all formats use "full frame" as the baseline. So in cinema Super has a crop of 1x

[@absolutelyeverything]

@@flyingfox2005 true but most modern camera manufacturers work on a “full frame” method and most people who watch these kinds of videos will need to be familiar with the modern terminology more than the high end/old school stuff

[@flyingfox2005]

@@absolutelyeverything except these are videos made by someone who works within the industry - he talks almost exclusively about high end cameras and lenses and yes part of that is 35mm film. This is not a KZbin channel talking about shooting on a mirrorless camera with cheap primes. People want to know about the industry, maybe they should used these videos as a learning situation, one that challenges their preconceptions and the lies they have been fed by camera and lens manufacturers... not to mention 100 KZbinrs who think filmmaking started with the Canon 5D. When Roger Deakins talked about moving to the Alexa Mini LF - no mention of crop factors, full frame etc. He referred to the lenses on the LF compared to the "35mm equivalent" - by which he was referring to the lens he would use on S35. When Lubezki talked about his lens choices on the Alexa 65 for The Revenant - he made no mention of crop factor or full frame. He again references the "35mm equivalent" ie: the lens he would use on the Alexa M or XT (S35) for the same angle of view. Many of the high end camera and lens makers (Arri, Leica, Zeiss, Panavision) don't revolve everything around "full frame"... because it's never been a thing in the cinema world.

[@KeshenMac]

You went through this entire video without talking about aperture and how you DO get an identical image if you also apply the crop factor to the aperture. 27 mm f/1.4 on APS-C (photography term) / Super 35 (cinematography term) will look NEAR IDENTICAL to 41 mm f/2.1 Full-frame (photography term) / Large Format (cinematography term)

[@chamayyamestre]

Thank you for information. From India

[@WillChao]

As others have explained compression has nothing to do sensor size, I’d also like to point out that depth of field differences can also be compensated e using different aperture stops. For instance shooting Master Primes on Alexa 35 at T1.3 versus shooting Signature Primes on Mini LF at T1.8, when matched for framing should yield largely identical results (lens characteristics aside). The super 35 setup also has the benefit of one extra stop of light when needed

[@ForlornCreature]

Oh my god please don’t peddle the bigger sensor size = more compressed garbage, this is misinformation that makes absolutely no sense. Larger sensor allows for more bokeh, more detail, potentially smoother focus rolloff, but does NOT magically compress the image to make it feel “bigger”. All of the other things are what have that effect. Compression is an effect of distance from the subject to the camera, and field of view. Almost any field of view and distance to the subject can be achieved on any sensor size (for most shots).

[@StephenFord]

We love you homie but compression works differently than you explained

[@jeyycie3656]

Ironically there is one major misconception in your video. Yes the sensor doesn't influence anything and it's the focal length that matters, but again that's not the actual millimeters on a lens that do that. It's all because of magnification ratios within the lens element, and the entrance pupil. For the depth of field for exemple, it's because to get the same aperture number, you need to physically enlarge that pupil. a 24mm f/2 as a much smaller entrance pupil diameter than a 85mm f/2, and this IS the parameter that changes depth of field. (if you close the iris to match the physical size of the entrance pupil of the 24mm, you will get the same DOP) So focal length is a consequence but not the direct culprit of those changes. In similar fashion, the actual focusing plane isn't on the sensor or film gate either, it's on the nodal point of the lens. In a lot of cases it isn't that impacting but for very long focal length at close focus, or macro shots it does matter. and that nodal point slightly moves in and out depending on the focusing distance.

[@fabiobarbati6029]

I think the concept you should have stressed to simplify what otherwise is a long and somehow confusing explanation, is that a LENS (with a certain focal length) is a specific 'vision', producing a specific type of image (compression, d.o.f., distortion, colours, sharpness, contrast...) ; it is like a specific brush for a painter. And that specific 'vision' doesn't change at all if we merely change the sensor format: we are just using only a certain portion of that 'vision'. This is the point! It is like if that painter would change the canvas size (sensor), using the same brush (lens). I think the confusion may come from thinking the sensor size (crop factor) as a determining factor, when that is only the "size of the canvas". Of course if we change the size of the canvas we would probably change the size/type of the brushes accordingly. But what many photographers and videographers continue to ignore is that THE LENS is the turning point, not the crop factor. And they don't know anything about optics. This ignorance, especially among still photographers, is also due to the general use of zoom lenses.

[@gokul_ml]

I think focal length itselt doesn't directly affect the depth of field. It's basically the distance between the camera(sensor) and subject that decides the depth of field. And also you have to decide the correct aperture to create the desired shallow/deep depth of field.

[@lefthandright01]

Bokeh and depth of field has always been a lens characteristic, never a sensor characteristic.

[@HarvestStore]

Great video.

[@okaro6595]

There is no lens compression. Compression or perspective is achieved by only the distance and the framing. How the framing is done is not relevant. I know this may be hard to get. It was for me 45 years ago. With depth of field you are right but it can be fixed by opening the aperture more on a small sensor - if possible (unfortunately it often is not and that is why larger sensors are preferred in photography)

[@richarddimery]

Take a full frame lens, change the back elements to narrow the image circle to match S35 (similar to how speed boosters work), you get the same FOV and DOF, but a higher exposure output, which in-turn, would help against the slightly worse sensitivity of the S35 sensor. This is why you tend to get faster APSC lenses relative equivalent Full Frame FOV. The relationship to the numbers change but thats about it. I think the differences between sensor size lay in the technicalities of the manufacturing and marketing departments.

[@AxTechs]

Love your videos, but there’s lots wrong with this one. Crop factor is measured at 1.0x when referring to 35mm stills film, not super 35 motion picture film. This is a major difference as 1.0x size sensors are actually Full Frame sensors such as the FX3. This means that S35 cameras such as the Alexa mini have a crop factor of approximately 1.25x or 1.33 with a camera such as the Komodo. Compression is also defined completely incorrectly in the video. Crop factor does in fact changes the perceived focal length of an image, and compression is directly affected by the perceived field of view of a lens, rather than the lens itself. Therefore, a 50mm lens on the Alexa mini, will give the exact same compression as a 65mm on the mini lf, assuming they are both in their open gate modes, or a 22mm on S16 (1.66) film. The only real difference that larger sensors give you, is higher pixel pitch at the same resolution, and a perceptually shallower depth of field when at the same field of view with the same T stop

[@flyingfox2005]

Crop factor in cinematography uses S35 (3 or 4 perf) as the baseline with a crop of 1x I suggest you get your hands on the Panavision documents discussing how to shoot on larger formats - S35, not "full frame" is the baseline - because for over 100 years S35 has bee the standard in cinema. Photographers and KZbinrs since the Canon 5D have pushed the idea that cinematography uses FF as the baseline... that is simply not true. Crop factor has no effect of focal length, perceived or other wise. Crop factor is a ratio between sensors that tells you what lens to use on a specific format to match the angle of view on another format. Compression is not affected by "perceived" focal lengths. Compression is the product of distance. Distance between camera to subject and subject to background. Therefore a 25mm lens on S16 has the same compression as a 50mm on S35 - as long as the distances all remain the same.

[@AxTechs]

@@flyingfox2005 You're saying exactly what I'm saying, I may have just worded it in a strange way, can you send me a link to that Panavision document, would be useful. Crop factor isn't really standardised from what I've heard to be completly honest, it only matters when you have a point of reference, e.g. the crop factor of a mini lf to an alexa mini

[@flyingfox2005]

@@AxTechs crop factor is a comparative tool - no format has zero crop... that is the main lie that manufacturers tell, as they want people to feel the need to upgrade from a "cropped" camera to one that is "uncropped". It's marketing - nothing more. The best thing to do is to take the horizontal measurement of the two sensors being compared and calculate that ratio. But if any format has claim within cinematography it is S35 (3 or 4 perf) - not "full frame" (8 perf) and yes you do see that in documents like those made by Panavision. The danger is people buying cameras or lenses based on wether a system is "cropped" or "uncropped"... there-in lies madness as people will often trade in a better S35 camera - for an inferior FF camera.

[@optimumfilms]

I've been using MFT for almost 20 years now and finally understand what all my lenses do...

[@dagonzalez1757]

There's one thing I don't quite get with crop factors smaller than 1. When they're bigger than 1, it's because the sensor only uses a part of what the lens let's through. So how does it work with factors smaller than 1? How can it get more data than what the lens can give?

[@christykail3314]

You're misunderstanding. A crop factor bigger than 1 means you're getting using part of the image relative to the "normal" sensor size, not what the lens can do. Large format lenses can cover a much larger circle than the "normal" sensor, so you can have smaller than 1 crop factors.

[@Kliffot]

It's just a ratio indicator, you need a larger lens that fit the larger sensor . That said many glass are designed larger than necessary for optimal performance ( sharp corner, low vignette) that's why for example many people put some FF lens ( EF / F DSLR usually ) on GFX medium format .

[@dgillphotos]

There’s an easy way to learn this. Pick up an older digital SLR camera versus a full frame camera. Shoot them side-by-side with the same lenses. The problem with the smaller sensors is that in order to get the same or relative field of you need a back up. Depth the field revolves around four factors, one of which is distance the subject. The best way to learn these things are just to shoot with various sensor sizes and be willing to learn. Most people will never understand these concepts while they stand and argue their points while holding the cellphone camera. The farther away you get from those people - the smaller they will appear.

[@flyingfox2005]

No - to get the same angle of view on a smaller format, you DO NOT move the camera, you change focal length. A 35mm lens on S35 matches the AOV a 50mm gives on FF / 135... and there is a 1.5 stop difference in depth of field. Adjust for that and the shots match. Moving the camera back changes the very nature of the shot.

[@thisischristor]

Sorry to pile on but it's not called a "micro four thirds sensor" (2:12). "Micro four thirds" refers to the camera system that uses a 4/3 sensor but doesn't have a mirror. Thus the cameras can be smaller (micro).

[@imagenatura]

Wow. Lots of mistakes in this video. I'm surprised you did what seems like a lot of research and editing but there are quite a few errors. Others have mentioned them.

[@jaschaeidam7469]

Will tie the "master photographer" who administered my journeyman-exam to a chair and make him watch this clockwork-orange-style. Dude hated my work based on it being shot on 6x7cm film (180mm lens) instead of a 35mm digital camera. Well, I think he mostly hated me, but still. (Got my certification, turns out somebody who doesn't grasp their field of expertise can't create documents that hold up in front of a judge)

[@gostriderful]

One big question. Is s35 equivalent to full frame? Or in cine world the standard sensor size is s35 (aps-c) instead of full frame?

[@6WeeksTV]

S35 is slightly larger than APSC

[@christykail3314]

No, this is a point that I think needs to be earlier in the video. The only time I hear crop factor being talked about is in relation to stills camera "full frame", not super 35mm which is closer to stills APS-C. A lens's "35mm equivilent" almost always relates to stills photography 35mm, not motion picture 35mm.

[@flyingfox2005]

@@christykail3314 not true! When a DP talks about "35mm equivalent" - they are referring to 3 or 4 perf motion picture film. Check out interviews with Roger Deakins or Emmanuel Lubezki when discussing their lenses choices for 1917 and The Revenant. Emmanuel Lubezki especially when talking about the lenses he used on the Alexa65 compares them to their "35mm equivalent" - a 24mm on the Alexa 65 compared to a 12mm on the Alexa XT. So the "35mm equivalent" is a thing within cinematography - but it uses 3 or 4 perf film as the baseline... not a photography format. I also have the Panavision documents discussing what lenses to use on 65mm cameras - this uses S35 as the "35mm equivalent" baseline... not so called "full frame"

[@timschneider8139]

@@flyingfox2005That‘s an interesting fact. I heard about it a while ago and discussed it with a representative from Sony who is a close colleague of mine. He told me that companies which did not produce 35 mm film cameras used to stick with the photographic equivalents in their digital cinema line up.

[@christykail3314]

@@flyingfox2005Interesting. I've been around a lot of film sets but I've never heard a DPs talking about crop factors at all, mainly just KZbinrs who are used to 35mm stills cameras.

[@digitaldevigner4080]

A fan of this channel but I would like to add that I think people are aware it’s not perfect. They are mostly interested in the framing and field of view. DOC and compression are of course factors but not nearly the desire to match as the FOV is. Plus adjusting aperture will compensate for the DOF part. A 1.5x factor is equal to a stop and a 2x factor equal to two stops. So a f8 50mm on FF will match the DOF and FOV of f5.6 35mm on s35mm. Roughly. At that point only compression is really different and I personally feel like that’s splitting hairs. Especially with a smaller move like s35mm to FF. A much larger jump like iPhone 2/3” to FF will have more noticeable compression but even then it’s not that big of a deal in my opinion. There is too much misinformation out there that has way over complicated something that should be pretty simple.

[@ddp227]

Great job. Thank You.

[@bobbydrake8965]

What Mic do you use? On your KZbin videos?

[@BryceMiguelWilliams]

These comments should be addressed in another video. It would make for good knowledge sharing and be better for the community.

[@frankhu8692]

Another major mistake, the crop factor only applies to filed of view but not focal length, regardless of sensor size, a 50mm is a 50mm, regardless of field of view, all sensor shares same perspective, thus regardless of sensor size, you never say that a 90mm on bigger sensor looks exactly the same as a 50mm on smaller senor

[@valcriston]

Wrong.

[@m.i.andersen8167]

Thank you for the video. 5:51 / 13:23 "...a wider focal length you will need to use" should probably be "A wider field of view you will need to use". You mention it yourself later in the video; that there are long and short focal lengths, but that it has nothing to do with the lens' field of view. An S16mm lens does not cover the image circle on a large format image chip, no matter if it is an 18mm or 75mm lens. There are of course some exceptions, for example the Zeiss Jena Biotar 50mm f:1.4 from the late 1950s, which covers the S35 format even though it is a 16mm format lens.

[@flyingfox2005]

No the video is correct - you need to use a wider focal length on smaller formats, for the same angle of view. A wider fields of view are only achieved using a wider focal length. A 25mm lens on MFT has the same angle of view as a 50mm on FF. The whole issue of coverage is irrelevant - as obviously if you are using a 9mm on S16 (to match the AOV of a 18mm on S35) no one expects the 9mm to cover S35...

[@m.i.andersen8167]

@@flyingfox2005 A focal length is not wider or narrower, but shorter or longer. On a single lens it is the distance from the lens in mm for parallel light rays to the point where the light hit the same spot, the focus point. When you talk about Wide or narrow it has to do with the field of view, how big an image circle can the lens cover with a decent picture. So you need a shorter focal length on smaller format to cover the same field of view as on bigger format. But the focal length does not determinate what size of image circle the lens can cover.

[@flyingfox2005]

@@m.i.andersen8167 a short focal length is also called a wide focal length. And no one said a short focal length determines the size of the image circle - please show me where that was said? But there are very few 9mm lens made for either S35 or FF... there are plenty of 9mm lenses made for S16 - as smaller formats require more wide angle lenses. But a 9mm lens could be made for S16, MFT, S35 or FF - on S16 it would give you the equivalent of an 18mm lens on S35 - and that is the point.

[@fernandooliveiralino]

Great video once again, thank you.

[@Crttr78]

S16mm and 16mm as a crop factor around 3. 3.41 in almost 16mm cameras. Blackmagic pocket cinema camera, 2.88 crop factor. MFT 2 crop factor ang GH5S 1,79.

[@fr33dom_s4int]

all the crop factor tells you is how close or far away you’ll have to put the camera to use the same lens.

[@flyingfox2005]

No crop factor tells you what lens you need to use on a different format to achieve the same angle of view. Moving the camera changes the entire nature of the shot.

[@JopaDP]

Could you do a cinematography style video for Bruno Delbonnel?

[@MichalKuzminski]

thank you for your content Sir, are you UK based? and Will you ever consider some live workshops?

[@ayouthwellspent]

You need to leave this video up. Your engagement is going through the roof with all the people correcting the factual errors!

[@DavidsOldChannel]

I wish you didn't add fuel to the fire of missinformation about compression and I'm quite baffled that someone like you doesn't understand it. Otherwise it's very informative video.

[@Skepdigger]

S35 has a cropfactor of 1.4-1.6, or am I missing something?

[@flyingfox2005]

That is only if you have bought into the idea that "full frame" is the baseline from which other formats are judged. Full frame was developed as a prosumer photography format - and it was developed from the already existing 35mm motion picture standard (4 perf) called by most people S35. S35 has been the standard for cinema over 100 years, while full frame was used briefly in cinema (as Vistavision) but has always been a niche format. KZbinr and photographers (post the Canon 5D) have pushed the idea that full frame is "uncropped" and the baseline. In cinematography - shooting 35mm refers to 3 or 4 perf film or a sensor around the same size... see the Alexa, Alexa35, F65, F55 etc. So in cinematography - S35 is the baseline, not "full frame".

[@JirehTorres]

Watch until the end of the video lol

[@Skepdigger]

@@flyingfox2005 super 35 and 35mm isn’t the same. 35mm ist the classic format from the 1890s. Fullframe is the equivalent of 35mm film. Super35 is smaller and from the 1980s. Apsc sensors have a similar size of super35 cameras. So technically it makes more sense to call full frame the baseline and not super35 .

[@flyingfox2005]

@@Skepdigger 35mm motion picture film - the standard for over 100 years runs the film vertically through the camera. This format is known as 3 or 4 perf - depending on the area used. This format is what cinematographers (not KZbinrs) call "35mm film. In terms of a digital sensor, this is referred to as S35. 3 perf gives you a 16:9 sensor and 4 perf gives you a 4:3 open gate sensor - the same size as the film stocks used on 99% of movies ever made. The so called "full frame" format dates from the 1910s. This took the same strip of 35mm film and ran it through a "stills camera" horizontally. This was known as the 135 format. The 135 format was developed for prosumer photographers. So - yes "full frame" is a prosumer format. It was developed from 35mm motion picture film. When used in cinema FF / 135 was called 8 perf or VistaVision and like the prosumer photography cameras ran horizontally through the camera. About 250 films were made on VistaVision in the 50s and 60s. In the 70s and 80s it was used to shoot VFX plates by companies like ILM. So no - calling "full frame" the baseline makes no sense what's so ever - as 8 perf was a very niche product and has never been the baseline from which cinematographers work. Arri refers to this format as LF - as it is a format larger than 35mm (S35). A S35 sensor, which is the same size as either 3 or 4 perf film however does make perfect senses as it gives an active area the same size as the most ubiquitous film format - "35mm" - known by most people today as S35.

[@flyingfox2005]

@@Skepdigger 35mm motion picture film - the standard for over 100 years runs the film vertically through the camera. This format is known as 3 or 4 perf - depending on the area used. This format is what cinematographers call "35mm film. In terms of a digital sensor, this is referred to as S35. 3 perf gives you a 16:9 sensor and 4 perf gives you a 4:3 open gate sensor - the same size as the film stocks used on 99% of movies ever made. The so called "full frame" format dates from the 1910s. This took the same strip of 35mm film and ran it through a "stills camera" horizontally. This was known as the 135 format. The 135 format was developed for prosumer photographers. So - yes "full frame" is a prosumer format. It was developed from 35mm motion picture film. When used in cinema FF / 135 was called 8 perf or VistaVision and like the prosumer photography cameras ran horizontally through the camera. About 250 films were made on VistaVision in the 50s and 60s. In the 70s and 80s it was used to shoot VFX plates by companies like ILM. So no - calling "full frame" the baseline makes no sense what's so ever - as 8 perf was a very niche product and has never been the baseline from which cinematographers work. Arri refers to this format as LF - as it is a format larger than 35mm (S35). A S35 sensor, which is the same size as either 3 or 4 perf film however does make perfect senses as it gives an active area the same size as the most ubiquitous film format - "35mm" - known by most people today as S35.

[@JeffBourke]

Super35 is crop factor 1.0 when we are in Cine Mode?

Uhm i think there are some thing wrong... super35 has a cropfactor of 1.6x but and is 24mm wide but there are many variations alexa mini has a cropfactor of 1.27x some other sensors have 1.5x...and fullframe is 35mm and has a cropfactor of 1x. The alexa 65 has a crop factor of 0.7x

[@MaximoJoshua]

Might be better to discuss the difference between Super35 and 35mm...

[@hiramesensei3112]

oh good, complete strawmanning in the first 60 seconds, this should be fun

[@xavieryt412]

It's funny because in the videography world (indie filmmaking...etc) the standard size is Full-Frame. So that S35 sensors are considered 1.33 or 1.50 crop factor.

[@JoATTech]

Hope everybody is aware that same F-stop with same crop on the subject (for example portrait) will have exactly the same depth of field regardless the focal length. Only thing changing is background compression which gives an illusion of "more bokeh". Same F-stop on different sensors will create different DoF ... This video is kinda misleading IMHO ...

[@flyingfox2005]

The video is correct. You are assuming that the camera is moved to create two different framings. Depth of field does change if you use an equivalent focal lengths on different formats. Using a 25mm f2 on MFT has two stops less depth of field than a 50mm f2 on FF / 135 - even though angle of view, compression and perspective distortion will be the same.

[@JoATTech]

@@flyingfox2005 By crop I mean framing, not different sensor sizes ... And I said same crop ... you talking about crop factor. This part is kinda correct in the video ...

[@verebellus]

I though that crop factor was 1x on 35mm full frame sensors, not s35 ones

[@flyingfox2005]

That's how photographers view things - in cinema S35 (3 or 4 perf) has the baseline.

[@verebellus]

@@flyingfox2005 so cine lenses that cover s35 are 1x crop and photo lenses that cover full frame are also 1x crop?

[@flyingfox2005]

@@verebellus There is a lot of bad marketing material used to sell cameras and lenses and one is to assume that sensors and lenses have "crops". Lenses project an image circle. A S35 lens has an image circle optimised to cover a S35 sensor. A FF lens has a larger image circle optimised to cover a FF sensor. Put a FF lens on S35 and it gives the same angle of view as a native S35 lens of the same focal length. The only difference is how much of the image circle is used. Put a S35 lens on FF and the image circle will vignette - as it is too small for the format. A crop factor is simply a comparative tool - it lets you match a specific angle of view on a different format. What format you say has a 1x crop factor is arbitrary - but the idea that all decisions in cinematography are based on FF / 135 is a lie. 95% of movies ever shot have used S35 (3 / 4 perf) - not FF which in cinema was called Vistavision. So in cinematography the convention is that we start from S35 as that is still the standard format.

[@chris_jorge]

Oh this one is gonna trigger tons of folks. 😂

[@DJDiarrhea]

Nobody who has any idea about what they're talking about thinks that crop factor is the only difference in sensor sizes wtf?

[@NKRDBL]

COMPRESSION

[@Max-lw2rt]

this is just straight up misinformation from the beginning, please redo

[@timthompsondp]

You can use T1.3 lenses on S35 - go learn how to light better and stop arguing about sensor size.

[@MWB_FoolsParadisePictures]

This is close but not quite right. Gerald Undone has a good video explaining the nitty gritty of crop factor, and Tony & Chelsea Northrup have a good video demonstrating an easy formula for applying crop factor to not only focal length but to F/T-stop (regarding its effect on DoF). Even a formula for ISO. But as a cinematographer shooting on a native ISO sensor, all you have to remember is to multiply both the focal length and the T-stop by the crop factor to get the equivalence (and then adjust your NDs or lights accordingly, obvi) if you're going to swap out lenses for the same FoV. In this case, a T/2.8 on Super 35 is more like an T/1.8 on Full Frame-not directly because of sensor size, but because if, when switching to a smaller sensor, you're changing to a wider lens to keep your FoV and distance from the subject the same, then your lens diameter at T/2.8 is going to be narrower than it was on the longer focal length when that one was set to T/2.8. So you'll have to open up to roughly T/1.8 to get the same DoF. If that isn't confusing lolol

[@Eissen_meteor]

Gerald the purple need to see this..

[@tomasdiaz2249]

La cantidad de pelotudeces que tengo que ir a leer en los comentarios, mamita querida!!

[@dylon2932]

S35 ≠ Crop Factor 1x 35mm AKA Full-Frame = Crop Factor 1x

[@vagabondcaleb8915]

How does everyone who talks about crop factor fail to bring up anamorphic?

[@vagabondcaleb8915]

If you think that you clearly are not understanding how one/either work.@@cicolas_nage

[@mattm7426]

Yeah... that's not how it works. Nice try though!

[@giancarlodambrosio230]

No esta correcto este video !

[@Vincent654]

Bro got roasted in the comments 💀

[@dwpix]

Why does this guy talk this way? With a 10-word “sing along” cadence. Fantastic information, but the vocal style drives me away after a few minutes. The inflection pattern is amazingly regular, like a droning sound. Sorry…

[@SSJ4Vegiito]

This video is racist AF. 😳