TECHNICAL: Full-frame lenses on APS-C cameras is USUALLY bad

[@franksamet]

I use full frame lenses on my D500 for two reasons: 1) I find the image quality excellent and very similar to using Cropped prime lenses 2) When I upgrade to a full frame in the future there won’t be the further cost of new glass.

[@andreasbuder4417]

That is actually only partially true. Because of this, you have excercise and familiarization with certain field of views (that is 1.5 crop of the focal length). If you switch to full frame, you suddenly use field of views much bigger than before. Now, you have to buy different lenses for matching field of views, if you want to keep your way of shooting. I have seen many people realising this mistake after the switch. For some focal length, however, you may have luck: A 50mm lens is the substitute for a 35mm on a crop. You may already have those two lenses. But a 85mm is no substitute for a 50mm on a crop, there is still a considerable difference in field of view. So, all in all: Buy lenses made for the sensor size, because after the switch, you buy new lenses most probably anyway.

[@nairbyad7188]

me too. he's lost his faculties on this.

[@marcd7332]

Andreas Buder That’s not a big problem, also a 50 on crop is a 75 so yeah an 85 is a good enough replacement on full frame, you won’t miss those 10mm

[@ikusanjay]

2 nd point is valid for me...

[@commenter4799]

I told myself that I'll keep the lenses when I upgrade, too. I'll never be able to afford to upgrade, lol.

[@peteanddrake4242]

The Northrops have been very adamant about their beliefs around light pass through and sharpness. They are working professionals (at least they used to be. they may be full time influencers now). As a working professional that started in the film days (1992--till now). My response to them is that none of what they have focused so much time on has mattered for a second to working professionals. I have shot every format. I've shot NFL and NHL APS-C (starting 2007) and never once worried if the f stop on the lens was literal or not. The Northrups think acceptable imagine started somewhere around 2013--whereas those of us who made a career in photography published and exhibited with whatever we (or our clients) could afford. Doesn't matter. I shot full frame lenses on APS-C for ESPN this week on a Canon 7D. 20 year old lens on 10+ year old body. Same paycheck. Same awards. Same "likes". Sorry, but any videos about stills photography made after 2013 are mental masturbation.

[@RobertFalconer1967]

"When you put an FX lens on a DX body, you're capturing less than half the detail that that lens is producing." This is incorrect and misleading. You're comparing images taken with different sensor sizes and inferring that the results are attributable to the lenses. The volume of detail is not a function of the surface area of the lens but of the sensor itself. You don't lose any of the potentiality of the lens by strictly using it's central portion. In fact, as you pointed out, the central portion is typically the sharpest part of any lens.

[@toddrobbins4608]

Ding ding ding ding ding! Gold star Robert. You are absolutely, 100% correct and you said it much better than I did. This video is complete nonsense.

[@marcdevries9027]

No, you are incorrect. When you put a FF lens on a crop body, you are indeed throwing away a lot of the detail that the lens produces. That same lens on a FF body will produce a much sharper image than on a crop body. So if you think you get the same performance of that FF lens on a crop body you are wrong. BUT crop lenses are usually of the same (or lower) optical quality than FF lenses. So the FF lens will perform just as good as the crop lenses. So in that regard there is no reason not to use FF lenses on crop cameras. If not for the fact that usually the FF will be more expensive than the crop lens as it has a larger image circle, which means more glas, which means higher price.

[@toddrobbins4608]

@@marcdevries9027 absolute nonsense. You are not throwing away any detail in the manner you think. The image circle is larger than what the sensor can resolve, yes. But the only part of the image that isn't being resolved is that tiny area around the edges that is larger than the sensor. Your not losing one iota of detail from what is being passed to the sensor within it's field of view. That is just complete nonsense and a total misunderstanding of how camera and lenses actually work. A DX sized sensor can only resolve a DX sized image circle regardless of what size image circle the lens produces. Your not magically loosing photons from within that circle that are adversely affecting the image in any way. Sorry but you are one hundred percent dead wrong.

[@marcdevries9027]

@@toddrobbins4608 It seems you have completely missed what I have explained. (And I think you misunderstand what Tony is saying as well) Let me try to explain it in a different way : Let's assume perfect FF and crop-C sensors that capture every bit of detail that the lens has resolved. And let's take FF and crop lenses that all have exactly the same optical quality. NOT perfect theoretical lenses, but lenses that have the resolving power of real lenses. And the FF and crop lens have the same optical quality for both lenses. We'll take a fictional FF zoom lens so that we can use the same lens to compensate for the different field of view with crop. We'll assume the zoom lens is equally sharp across the range. And use the sharpest f-stop. This way we can shoot equivalent pictures where the lens performs the same in each situation. In real life this is impossible to accomplish, but for understanding the point assume such a zoom exists. We now have three options: FF sensor + FF lens. APS-C Sensor + FF lens. APS-C Sensor + APS-C lens. We shoot three equivalent pictures and display them at the same size. e.g. fullsize on your PC monitor. The results will be as follows: The pictures from the APS-C sensor + FF lens and APS-C sensor + APS-C lens will be EXACTLY the same. (Which I think is also what you are saying above) But the picture from the FF sensor + FF lens will be a lot sharper. In this regard there is no reason why you should not use a FF lens on an APS-C sensor as it produces the same image quality as the APS-C lens on the APS-C sensor. BUT the situation can change when we consider real life lenses. Especially for wide-angle lenses. Making a wide-angle lens that has a large image circle is more difficult and uses more glass than a lens with a smaller image circle. So if I use the same quality glass in a FF and APS-C lens, the FF lens will be more expensive and heavier. Now the part where I disagree with Tony. In most situations you don't have equal FF and APS-C lenses. Even with Canons big lens line-up there are only a few situations where you have comparable lenses.

[@toddrobbins4608]

@@marcdevries9027 now go back through, let's assume that all your givens and work arounds and all that if we lived in a theoretical universe and your still dead wrong. What your trying to do here is say that because one image is "higher megapixel" that it's sharper. No, it isn't. It's just a larger image size on the full frame and mp equals length times height. That does not mean that the higher mp image is automatically sharper. At no point we're magical photon stealing Gremlins involved. Very simple test to prove my point. Take a full frame lens, attached to a FF camera. Coat the exterior lens element in Vaseline. Take a test shot. Then take an APS-C lens or a full frame lens, your choice, on an APS-C sensor and shoot that without Vaseline. The lower mp apsc shot will be sharper. The amount of mp does not equate to image sharpness. It's that simple. This perceived mega pixel argument is complete hogwash

[@zFLAVEz]

When I was starting out buying camera gear and lenses, I had trouble justifying APSC only lenses when I knew in the future I wanted to upgrade to full frame

[@pdotc]

That's what I was going to say. Especially with so y since no adaptation is needed.

[@johncampbell335]

Just starting to watch now; was hoping he covered this. It's a major factor in the upgrade path.

[@keithgoreham1463]

When I had my old D50, I bought full-frame primes and 2 APS-C zooms, with the intention of going full-frame eventually. Worked out pretty well a decade later when I moved to the D750 and then the D850.

[@footsy420]

I went straight to a sony a7iii then i bought my wife an a6400. Now for shooting wildlife or macro the cropped sensor is superior so it depends what you want to shoot. having both is wonderful though I might be happier with a single riv though i wouldn't have a backup.

[@AngelusHD]

@@footsy420 Right there with you, but having a A6400 separately for video work and wildlife/macro and sharing video/photography with your wife is a lot better than be restricted with just 1 camera. Now having the A7IV and a A6400 but better having an A6600 because of the batteries is the winner combo. That being said, there is always a better option which cost probably a lot more money and if u can afford it go for it. I think the A7III and the A6400 is a great value for the results we get which is imo what counts.

[@DarrinHowells]

I've used full frame lenses on a crop body because I knew I was going to eventually move to full frame and didn't want to have to re-invest in full frame lenses. With the differences being so minimal for a recreational shooter, that was the smartest financial decision for me.

[@Paulygotthatd]

Thank you. This has been the question I was wondering. I plan on upgrading my body eventually.

[@touristguy87]

It would have made more financial sense if you'd just stuck to using your cellphone

[@potatofuryy]

@@touristguy87 What are you trying to say?

[@touristguy87]

@@potatofuryy read

[@potatofuryy]

@@touristguy87 kinda long-winded way to say "read" but ok ig

[@mikehenthorn1778]

So bottom line use the best lens you have and if you're happy with the results it's all good.

[@LeroyLegacy]

It took him 19 minutes to say that? Lol

[@pow9606]

What happens if you haven't got a lens. Which is the best lens to have? Think that is the real question. Don't want to buy a tons of lenses to determine that. Ye?

[@mikehenthorn1778]

@@pow9606 well if you don't have a lens then you only have half of a DSLR right. otherwise think about what you want to shoot and get a lens that works for that. there is no best lens, there is only what works best for you.

[@Leo9ine]

"The same FF lens would be better on a FF body than on an APS-C body" Okay, yeah, but the real question is *"would that same body be better with an APS-C lens instead of a FF lens?"* If you're going to use an APS-C body either way, then which is better? The constant should be the body, not the lens.

[@mikulmusic32]

Dude I was thinking the same thing. The whole time I was thinking DUH! Obviously no one needs to be convinced that FF cameras capture more detailed images. People use FF lenses on aspc bodies because as long as you don't mind accounting for the crop factor you probably figure it's just as good as the aspc equivalent, and you have a lens that works on both of your cameras with no other downsides.

[@touristguy87]

@@mikulmusic32 cept the aps-c lenses are cheaper (and often smaller and lighter) , and for good reason: they don't have to match the ruggedness, sharpness or speed of FF lenses

[@trulsdirio]

Honestly, I use Sony A mount and only have full frame Minolta lenses. They are cheap (like I got my 50mm 1.4 for 40€ with a flash, film camera which I still use, a second Sigma zoom lens and a few other things) and of superb quality. Yes, the edges don't live up to modern 1000€ lenses, but guess what, I don't use the edges on a crop sensor, so get tack sharp images all the way to the edge of the frame.

[@gliazzurra]

Dude is asking the wrong question. Of course FF sensors/bodies are better. They need to be to justify the extra weight.

[@EtherealSunset]

​@@touristguy87 not always when buying secondhand. Sometimes a ff can be the same price, but have better build quality like weatherproofing.

[@HussainAlkumaish]

I have nothing against you Tony, but there is so much wrong in this video, I can't believe for a second that you don't realize it. You could've cropped the FF image to match the crop sensor, because this is exactly how a crop sensor works. Use the same lens, same distance, same aperture, and same focal length if you're using a zoom, then you can actually say that you are comparing the results objectively. I'm sure you know this already, which makes me think that you used zooming (or suggested changing the distance) just so you can prove your point. Using your method to test _will_ produce skewed results which makes your conclusions inaccurate and misleading.

[@MrJed_s]

So in a real-life scenario you'd crop the FF image instead of zooming to fill the frame?

[@HussainAlkumaish]

@@MrJed_s this has nothing to do with real life scenario. This is a test of lens performance on different sensor sizes. lenses don't perform the same when you change zoom, aperture or even focus. Albeit this is irrelevant to this discussion, but you asked: yes, I would crop instead of zooming if that would give me a better picture.

[@MrJed_s]

@@HussainAlkumaish what I'm getting at is that in real life, the composition of the photo isn't dictated by the sensor size. So Tony's experiment reflects what any normal photographer would do, standing in the same spot, wanting the same composition with either a fx or dx body in hand.

[@HussainAlkumaish]

It is only natural that you don't get the same _result_ from different-sized sensors when using the same lens, but that doesn't make the lens any less or more sharp. The image will still look as sharp on FF when you're using the same focal length, in fact it might look even less sharp on FF than on crop because zoom lenses are usually less sharp as go further away from the center. If you still can't see how inaccurate and misleading the video was: Think of primes, it is simpler. No zoom, is it still not as sharp on a crop sensor?

[@davidellinsworth22]

@@MrJed_s this isn't about real life. It's a scientific test of how a lens performs on different sensors. In other words, to be scientific there can only be ONE variable when comparing, I.e. the sensor. You CANNOT change sensor AND focal length then make your mind up for yourself which variable is responsible for your observation.

[@huepix]

The difference your showing is to do with focal length not crop factor. The fact is there is no difference. The part of the image circle that hits the cropped sensor is exactly the same part of the image circle that hits the part of the full frame sensor that correlates to the cropped sensor. It just has the extra bit of sensor that gets the extra part of the image circle. Your comparison is valid only in the sense of achieving the same composition, but that is a different thing. One would need to use a prime lens and then compare the same sensor area (the central part of the full frame v the cropped sensor) and then it's more really comparing the fidelity of the individual sensor.

[@gonmax]

The guy on the video uses vague arguments and asumptions, a more scientific approach please.

[@siewkimng1085]

That isn't how you use lenses. People don't deliberately crop their FF framing to match APSC when they shoot. You would pick a 55mm in APSC and then 85mm in FF to get the same field of view when you shoot. Tony is right to say that using FF lenses on APSC bodies will generally be more expensive, heavier and deliver less sharpness than using APSC specific lenses. Technically if you compared the same image circle of the lens of course it will perform identically. But then it's like buying a 50 MP camera then measures the image sharpness after cropping to APSC format - that's deliberately putting FF at a disadvantage.

[@elbajomundo]

Your´re right. This experiment doesn´t make any sense. To compare the image quality of both lenses, he should have compared a full frame lens with an APSC lens on the same APSC camera. If you modify all the variables of the experiment, in the end there is no way to identify what influences the results. This experiment is very poorly planned.

[@TunaSoda]

@huepix ^ this is exactly why this video is skewed, nobody seems to understand this lol

[@drchtct]

You really didn't understand anything of the video, his point was not FF vs APSC, it's about which lenses to use on which body (don't use FF lenses on APSC body, it's a waste of money, resolution and size).

[@jdw715]

Shoot at the same focal length but magnify the image. You're shooting at two different focal lengths of the lens so this isn't a good comparison. A zoom might be sharper at one focal length vs another. Use a prime.

[@WesPerry]

John Williams he talks about this 1/3 of the way into the video.

[@robph8421]

The 2 other things he suggested, adjust the distance and adjust the F/n, will end up with the same apple orange problem. The lens should be kept exactly the same for the 2 shots, the comparison then made between 2 equally physically cropped areas. Of course provided the pixel counts are not too different.

[@davidellinsworth22]

@@robph8421 I suggested this also. D850 Vs D500/D7500 would be the ideal comparison because their pixel densities are almost identical

[@robph8421]

David Ellinsworth I always like Tony’s posts except wherever he brings up issues that concern crop vs full frame, where I think he’s off both theoretically & practically.

[@eltouristoduo]

@@robph8421 As odd as it may seem, I think for practical information on this subject we should compare prime lenses of focal lengths that are relatively shorter than the crop format lens, by approximately the crop factor amount. So we should for example compare a FF 35 mm prime (on a mount adapter) vs an APS-C 55 mm.

[@thesharpercoder]

I am sorry, but applying crop factor to aperture is simply wrong. Crop factor applies to the angle of view, not exposure. Aperture applies to exposure, not angle of view. Please stop conflating the two. I have never seen a light meter with a crop factor. Have you?

[@thesharpercoder]

@tyvek05: Some FF cameras have a “crop mode”. Theses cameras all work in basically the same way. Crop mode only uses pixels in the center area of the FF sensor. You can use “crop mode” with a full frame lens. This is equivalent to using a FF lens on a crop sensor body. Guess what the images look like when the camera is in FF mode vs Crop mode. The images will look identical. The only real difference is the crop mode produces a cropped version of the full frame mode image. BTW, when you find a light meter with a crop factor, please let us know.

[@commenter4799]

To compose the image exactly the same, you apply crop factor, like you said. However, aperture isn't only used to determine exposure, but also depth of field. You may apply the crop factor to aperture because to frame the photo the same way with a crop sensor you either have to zoom out or get further away from the subject, and both will increase depth of field. So, my 50mm f/1.8 on a full frame will have more background blur than my APS-C because I have to get further from the subject to frame it the same. If you multiply the aperture by the crop factor, and use the new number on the FF, you'll get equal bokeh in both pictures. No one says exposure is effected by crop factor.

[@commenter4799]

Correction: Tony does say that exposure is effected. Because ISO is based on light hitting per square inch, a smaller sensor gets less total light in a given picture. However, because sensor size isn't taken into account, full frame or crop sensor cameras will have the same ISO with equal apertures and shutter speeds. This is misleading because the sensors on crop cameras, though the ISO number is the same, actually need higher gain which is why crop sensors tend to be noisier at higher ISOs. So no, a light meter doesn't have to account for crop factor because the software in the camera does. However, that light meter won't tell you how noisy the picture will be. I think this can be demonstrated with a 6mm sensor, the pupil, and an astronomy telescope. If aperture is the focal length divided by entrance pupil, then a 1000mm focal length scope with a 100mm entrance pupil will have the same aperture as a 100mm focal length scope with a 10mm entrance pupil, but the 100mm entrance pupil is 10 times the diameter of the smaller, so, much more light is being let in. Not even linear since area is on a curve. So, the pupil being the sensor and staying the same, two telescopes with equal apertures have vastly different light transfer. Take that to a crop sensor, and it sees 1.6 times less surface area for a given focal length as the full frame. So, the light reflected off of a surface reaches the lens, but 1.6 times less of the area, so total light is 1.6 times less, thus a darker picture. The camera accounts for this and increases gain, but the light hitting per square inch is the same, so while it has to be more sensitive, the ISO number stays the same. Thus, noisier for the same ISO, but no noisier when given equal light. So, your aperture may say f/1.8, but be closer to an f/2.8 in light transfer with a crop sensor. Thus, all things equal including the framing of the shot, the crop picture will have more noise. If you take the same shot, but change the aperture of the full frame to 2.8 leaving the crop on 1.8, and increase ISO to account for the less light coming in, you'll get similar noise levels, because light levels are equal. In summary, the settings on your camera will not change from a FF to a crop with a given aperture, but noise will because you're getting less light to the smaller sensor which then needs to compensate.

[@MsIrrealis]

It does affect the f-stop by definition.... so you do need to apply the crop factor to both or to neither. You are correct in saying that crop factor does not apply to exposure.... as that is t-stops and not f-stops

[@TexpatOTG]

I think this is wrong. Light coming through the lens isn't digital, it's analog function. (if both sensors are same ) Of course if you use an crop lens on a full frame you won't utilize the full frame sensor to it's maximum resolution. If you use a full frame lens on a crop sensor it will give full coverage on the sensor. I don't believe you'd see a difference in the full frame or the SEL when used on a crop sensor camera - you would however see a difference using a crop lens on a full frame because it can't cover the entire sensor. Am I missing something?

[@user-wd3ot8kr4v]

man all this pixel peeping when most of people's work end up posted on instagram where all these minute differences make 0 difference lol.

[@ryancampbell1151]

This is absolute nonsense. The ONLY difference is the level of crop. There is no such thing as a perceptual megapixel. Even using a full frame lens on a full frame sensor there is a crop. This is just false information.

[@vipersrt30]

perceptual is a made up term to identify the true resolution of a lens + camera combo because lenses are usually not optically perfect.

[@ChristopherKemsley]

This is not true. As the previous commenter says, lenses aren’t perfect. A perfect lens would focus a single point on your subject onto a single point on the sensor, but a real lens won’t. A real lens will have a little bit of imperfection and blur. If that blur is bigger than a pixel, then it bleeds into neighboring pixels - thus creating an image that’s perceptually lower resolution. Physically there’s a limit too. If your aperture is too small, you’ll start getting an Airy Disk that’s bigger than a pixel, and you can’t overcome this without increasing the aperture. Orrrr you can increase the size of the pixel, which is what a full frame sensor does. In both cases, having larger pixels (larger sensor) keeps the blur of lens imperfection and airy disk on the same pixel in a wider range of cases, thus leading to a higher perceptual resolution.

[@jeffberg8015]

I agree with everything Tony says about comparing lenses on cameras of different sensor sizes, but as to the title subject of this video, full frame lenses on APS-C cameras, I somewhat disagree. I shoot a Nikon D7100 and have a mix of full frame and APS-C lenses for it. I tended to choose my lenses more for what they cost versus what format they were designed for and found some great values on used full frame lenses. I'm not a pixel peeper but have found very little difference in sharpness between the two lens formats on my camera. The reasoning behind why I think this issue is overblown is this: glass is glass. All lenses are designed primarily to render a focused image at a certain distance. The size of the sensor at that distance should have nothing to do with the sharpness rendered per unit of sensor area. Now, I can see where APS-C lenses could have some slight advantages in some areas. For example, they may have less errant refraction of light because of the smaller light gathering area needed and lower amount of glass the light must travel through in order to render a smaller image window, but I've found, and believe the data backs me up, that these differences are pretty slight and that full frame lenses will indeed work fine with APS-C cameras. As an example, the Nikkor 35mm 1.8G DX lens has a lower DxOMark sharpness score on the D7100 than any of the 3 Nikkor 35mm full frame prime lenses listed there. So, my advice is to buy whatever is cost effective for what you want to shoot.

[@3W14]

Jeff Berg good point but one thing to mention. Dxomark score of 35mm dx f1.8 lens is not true. They didn’t measure f2.8 and estimated it by averaging sharpness at f1.8 and f5.6, unlike other measures. Lenses tend to get drastically sharper at f2.8, which means the score doesn’t make sense at all. Dxomark “tries” to be accurate and I respect their work but we should be careful not to trust the numbers regardless.

[@NalinKhurb]

The Nikkor 35mm 1.8G lens costs substantially less than the FF alternatives. If you used a pro DX lens it would make for a better comparison

[@jamoncitovideos]

That 35mm 1.8dx is such an inexpensive and amazing lens. Everyone who owns a Nikon DX camera should own one! I use it with my D500 and it's one of my favourite lenses, and I only paid 120€ for it!

[@thdman15111]

I would buy full lens for my Crop Sensor in preparation to get a full frame camera.

[@jeffberg8015]

@@3W14 I checked on what you say, and it's true there are no results listed for the 35mm DX lens between f1.8 and f5.6, but comparing the 35mm f1.8 DX lens to the 35mm f1.8 ED lens in those settings where both were tested it looks like the results were almost identical at f5.6 and f8 while the DX lens looks sharper at f1.8 and the ED lens looks sharper at f11. Would testing the DX lens between f1.8 and f5.6 have changed the overall score? Possibly, but I saw nothing there to indicate that the DX lens is going to be automatically sharper on an APS-C camera and stand by my original assertion. Thanks for pointing out the discrepancies though.

[@Photojouralist123]

Tony again you're wrong!!! I'm a professional photographer and I use full frame lens on a D500 in all sorts of conditions and no problem. In fact during the old days of a D1x and D2x we could only use older large Nikon lens from Nikon film cameras . I've gotten many front covers for WSJ, Washington Post, Boston Globe, CNN etc. My photo editor at AP had no problem and the picture editor is like god. So your wrong bro sorry.

[@MrYankee853]

exactly..thats why wildlife photographers like Steve Perry do the same thing..dont know why Tony puts some of this stuff out there

[@WilliamJohnston]

He never said you can’t get professionally sharp images with dx/dc combos, only that in some scenarios, using fx lenses in dx bodies can be bigger, heavier, more expensive and less sharp than an equivalent lens designed for apsc... which he admitted isn’t always possible, and he addressed wildlife separately where dx has some advantage unless using a 60+mp ff sensor. Watch the whole video next time before jumping to wrong conclusions!

[@danteojeda2023]

I'm sure he also is a professional photographer, but he made experiments and investigation, so why do you think you know more? To start with, he says it is less sharp than in full frame bodies, not that they are not sharp at all

[@TCGhits]

I don’t see what’s the big issue. There’s a reason why Nikon does not produce many DX lenses. IMO you can use FX lenses with no issues. 🤷🏻‍♂️

[@chosenideahandle]

I don't think there is a big issue either. Nikon has been run into the ground on the other hand.

[@TCGhits]

Chosen Idea that’s because they didn’t get into the Mirrorless game for a while. Before that they were fine

[@chosenideahandle]

@@TCGhits yes, that was their first mistake.

[@saiiiiiii1]

Nikon has been going downhill for a long time. Producing new lenses costs money which they lack. The best Nikon pro aps-c standard zoom is still the 17-55 2.8 which is quiet bad by current standards. Even 10 years ago you had to buy a FF lens for your pro Nikon aps-c camera.

[@toddrobbins4608]

Yanis, that is not just your opinion. That is an absolute, empirical, proven fact. This video is complete nonsense.

[@pauka13]

so when I look trough a smaller window I see less details of the outer world? I don't think so...

[@MrYankee853]

bingo !! he is so wrong

[@freecycling6687]

Or - if you crop into a 35mm film frame, it would be less sharp than the edges?

[@tomwd.2825]

Perfect example! Right on the spot, sir.

[@marcdevries9027]

When your eyes are smaller and the window has a limited amount of details it can project on your eyes, than YES you would see less detail through a smaller window. That's where your thinking go wrong. But let me explain it in a different way that would be easier to understand. Lenses have a limited amount of detail they can resolve. That image with that limited amount of detail is projected on the sensor. To make it easy to understand I'll compare the resolving power of on the sensor with a resolution of detail per inch: dots per inch. Lets say the lens can resolve 1000 dots per inch at the distance of the sensor. And let's say my crop sensor is 1 inch wide. That means I have 1000 dots in the width of my shot with the crop sensor. A full frame sensor is about 50% wider. So on the width of that sensor I have 1500 dots. So the picture show with the full frame sensor has 50% more detail in the width of the shot. (and of course also the height) It's exactly the same lens, with exactly the same sharpness. But in the full frame shot you get more detail. Now of course the edges on the full frame are worse than with the FF lens on the crop body. But those edges have to be really bad before the crop looks better, because that FF starts that big advantage. If the edges are 30% worse in FF than in crop, than it's still equally sharp. You need to have a lens with really soft edges before the crop cameras has an advantage in the edges.

[@pauka13]

@@marcdevries9027 thank you for the detailed reply! Hopefully I can test full frame glass on my crop sensor camera soon and see what's de real difference compared to my dx lenses.

[@theizza68]

With sigma's contemporary trio, 16mm f1.4, 30mm f1.4, and 56mm, the Sony aps c cameras are the best option for people with low budget. They produce professional quality results and are affordable. Fujifilm's equivalent lenses are probably slightly better but cost twice as much. Canon and Nikon can't compete YET. So many KZbinrs seem to ignore those lenses for some reason.

[@josephfinkleman8358]

Tony this was not a scientific test since you changed the focal length. I am a retired professional, commercial photographer. I use FF lenses on my crop sensor and they are wickedly sharp. They are sharp because I am largely using the center of the lens and the near borders. I have a FF Nikon system, 36Mp, and 45 Mp. I also have a Fuji system, 24 Mp and 40 Mp. Fuji lenses if one is discerning are high-resolution professional lenses. However, the same is true for Nikon lenses. My 300mm Nikon Prime is noticeably sharper than my 70-300 Fuji zoom. To just be really fair my Zeiss 15mm is much sharper than my 14mm Fuji lens. My 50mm Nikon lens at f/5.6 is sharper than my Nikon DX macro at f/5.6 and it is a great lens. Now, my 27mm Fuji lens is slightly sharper than my 28 Nikon lens, but they are really close. The 27mm is an outlier lens in that it was designed to be ultra-sharp. My 85mm Nikon lens at f/5.6 is sharper than my 80mm macro Fuji lens. In no sense are the Fuji lenses inferior, it is simply on the FF lenses I only am using the center.

[@barmalini]

how could a great FX lens get to know that it's mounted on a crappy DX body, to produce a less sharp image for that DX? It could not. It has no idea on which body it is mounted, so it will deliver always, always, Tony, FX lens will always produce image of the same quality, no matter what body and what adapter you use. It is a given fact. If you want to argue about that, please argue off camera, because people who could believe in that argument wold not be able to even open youtube, and the rest of us know that any particular lens, on any day of the week, no matter what, is always producing the same image quality: one lens - one image, one sharpness, one bokeh, one microcontrast(though i do not believe in the latter).

[@siewkimng1085]

The lens will produce the same image sharpness but the camera will not (at the same framing).

[@drchtct]

It amazes me how few people in the comments understand the video. Simply put, use FF lenses with FF bodies and use APSC bodies with APSC lenses. If you use FF lenses on APSC bodies, you're only using the middle of the image, which means unless your lens is a $2000 G-Master pro grade lens, it will not be able to resolve the high-density APSC sensor (you're also carrying twice the weight compared to APSC lenses). This is not a weakness of APSC cameras, it's user error. APSC cameras produce fantastic images once you put lenses on there which were designed for the smaller, higher-density sensor. Since Fuji is the only system that has no FF upgrade path, their system provides you with the biggest choice of high-quality APSC glass. All other manufacturers want you to go to FF eventually, so they hardly produce pro-grade APSC lenses. This is not a shortcoming of APSC, it's a shortcoming of the available or used lenses of that Sony/Nikon/Canon system.

[@derryk1]

All my lenses are full frame "pro grade" and I used them on my Lumix GH5 and even my G85 with no problems and no complaints from actual clients. It looks great and best of all they will look great on my full frame Lumix S1R and which ever other camera body I use. Marry the lens, date the camera body.

[@christopherleachman5903]

Mary the lens date the camera. Too right!

[@oldfilmguy9413]

NO! NO! NO! Optics are optics. Optical principles are optical principles. Using the same lens any image is the same - differences have to be in camera sensors, software etc. Only difference as far as the lens is concerned is how much of the image is cropped (image circle out of the back of the lens is the same).

[@zoranzaric8256]

And the resolution that the sensor is providing on the same area which is exactly what Tony is talking about. The optics is the same but the details resolved depend on the sensor. Same reason why the lenses that were considered sharp on 16 MP FF sensors are not sharp on 30 MP and up.

[@cbflazaro]

smaller sensors do not affect aperture/DOF. "stepping back" to "match the composition" affects DOF. taking photos on the same spot with a 50 1.8 will have the same dof/bokeh as a m43's/apsc/fullframe/medium format with a 50 1.8 taken on the same spot.

[@WilliamJohnston]

Nobody’s disputing that

[@HelloFellowDinosaurs]

Lol what!? You couldn't be more wrong if you tried. Sensor size absolutely matters, you just have to take a lot more steps to counter it, Tony already did a video a while ago called like "Does full frame matter" or something. There's a reason my phone, having a 135mm F2.2 telephoto, doesn't get any Bokeh in shots. Put a 135mm 2.2 lens on an APS-C and that changes drastically.

[@WilliamJohnston]

Mc GetRekt I don’t know what phone you have, but I’m 99% sure it’s not a true 135mm, just the equivelant to a 135, which is a lot different. The iPhone ‘28mm equivelant’ main camera is actually a 4mm lens or something, and that’s one of the reasons it produces no natural bokeh, it’s just a huge crop of a 4mm 1.8 lens, replicating the look of a 28mm f13 on ff. Tony has addressed this many times, but Bruno is also totally correct here, a 50mm lens will produce the same DoF on any sensor, it’s just smaller sensors crop into the image more, making it look more like a longer lens, and when you compare that against the equivalent longer lens with the same aperture on a ff camera, the original lens has less dof than the longer one you have to compare to. They’re both right, and no reason to get emotional over it.

[@HelloFellowDinosaurs]

@@WilliamJohnston The Huawei P30 Pro. It is a true 135mm. It's a 70-135mm F/2.2 8mp sensor, and main sensor is a 40mp 34mm F/1.6 sensor.

[@WilliamJohnston]

Mc GetRekt I’m sorry that you think that, but you’re just wrong - the p30 pro has a 1/1.17” sensor with a crop factor of 4.6x... so your ‘135mm f2.2’ is actually a 29mm f2.2 which behaves more like a 135mm f10, even though it has the brightness of f2.2. So the reason there’s no background blur is it’s a 4.6x crop of a 29mm f2.2. Look it up, sorry to sound rude but you’re just wrong. If it was a 135 f2, on your 4.6x crop sensor phone camera it would behave like a 620mm lens...

[@OlegKorsak]

A7RIV has a bigger sensor than a6500, BUT at the same time its pixel size is SMALLER. Should it be worse then? Another example: Switch FF camera with FF lens to a crop mode... should it become worse automatically while nothing really changed? bullshit

[@cudackedees3327]

Wow so tony doesn’t know that 16-35 is least sharp at 35mm?? Did he rent the lens!!

[@w9fcc]

Wasn’t going to comment. There are hundreds of comments, probably thousands soon. But still, just can’t resist! I like Tony’s videos and highly respect his intelligence and scientific knowledge. I do disagree on this topic. I really need a blackboard to explain, but I’ll try a few words... For simplicity, let’s say I use an 85mm prime lens designed for a full frame sensor, and also an 85mm prime lens designed for an APS-C sensor. I take a picture of a book case in my home, zooming with my feet to fill the frame. So the book case fills the sensor in both the full frame camera body and the APS-C body. Both sensors are 24 megapixels. The book case fills the sensors of both cameras completely. So, we have an image of the book case using the entire sensor of the full frame and APS-C bodies, all 24 megapixels are used in both cases. There is no reduction in resolution at all; there can’t be. In both cases, the book case image fills the sensor, using 24 megapixels. DXOmark is useful in comparing lenses, but their virtual megapixels theory is not really very useful or valid. They seem to be trying to describe the crop factor in an APS-C body in a peculiar way. True, the APS-C designed lens does produce a smaller circle on the sensor, but simply zooming slightly negates this effect. The subject, the book case in this example, fills both the full frame and APS-C sensor, using all 24 megapixels. You simply have to stand back a little more from the subject to compensate for it. (or zoom the lens out slightly if it’s a zoom lens) When you’re doing extreme pixel peeping, there are many factors that can affect the sharpness. In Tony’s tests, he used two different cameras and sensors. Even the tiniest difference in focus or sensor could easily cause an apparent difference in sharpness. So there’s my take on it. Again, with probably thousands of comments here by now it was probably a waste of time; but I feel better. Now, more coffee!

[@MrYankee853]

bingo ! Tony has valuable info on some things, but completely missed the boat on this one

[@ofmetalphilosophy4837]

whenever I receive a notification from this channel, I prepare myself for a discussion and explanation on the words 'sharpness', 'sharper', and 'not as sharp'.

[@joshrock]

As usual you are discounting a major factor. The fact you're blowing up the apsc twice as much as the full frame certainly is affecting the visible sharpness. Also as you point out zoom lenses aren't always as Sharp at all focal lengths could be a factor. If you wanted to test accurately you'd take both at the same focal length, then crop the FF down to 1.5 crop, and compare.

[@popcornparam]

Oh wow that's so interesting.

[@alphaxfang]

Blowing up the apsc image? Both use 24mp i don't think tony blow up any image... Yes different focal length in zoom can give you a slightly sharper image and usually it is sharper in the wider end of the zoom lens and it means the crop body should have sharper image... Yet the test result speak differently... If you use same focal length and do the crop then you will blow up the FF image since it will be 16mp ff vs 24mp apsc...

[@_antoniocouto]

Josh Sporre agreed

[@joshrock]

@@alphaxfang honestly I don't understand how you don't get that viewing an image from two sized sensors at the same size causes a discrepancy.

[@TonyAndChelsea]

Well, yeah, that's why the FF is sharper, because APS-C is more magnified. But in the wildlife section I showed APS-C is sharper if you have to crop. We totally agree with each other.

[@angumotzfeldt3093]

Wow.. I didn't know perceptual megapixels existed. I just thought the image was projected from the lens to the sensor.

[@MrYankee853]

haha...you're right..no such thing as perceptual megapixels..it just sounds good to Tony

[@timothylatour4977]

You know what he means -- you're just trolling him now. PMpix is simply equal to the result you would get in a perfect scenario with a sensor with that many Mpix. With a perfect lens, PMpix = Mpix.

[@timothylatour4977]

@@MrYankee853 Of course PMpix exists. With a perfect lens, the f stop and t stop are equal, and with that perfect lens PMpix = Mpix. In all other cases, PMpix < Mpix. Simple.

[@jamoncitovideos]

This is simply incorrect. You cannot compare sharpness between sensors if you are using a zoom at different focal lengths. That zooms perform differently at different focal lengths is a straight up fact, so doing this comparison is like using two completely different lenses. The whole "we use different focal lengths to get the same field of view" does not make any sense when trying to compare sharpness. The correct comparison would be to stick the same lens at the same focal length (using a prime would be ideal) and at the same aperture in an aps-c and a full frame body, and then compare the sharpness between the crop sensor and the full frame being used in crop mode (or cropping it in post). It's sad that such a big KZbin channel is misleading less experienced photographers, specially by making videos masked behind a layer of supposed science to prove their opinions. And comparing two things which are not in equal conditions is just not a correct comparison.

[@jamoncitovideos]

@Chris But the point is not to test how much sharpness can you get at a fixed field of view by using different lenses, this actually would depend on the available options in the market and not be a good comparison. Sharpness varies when using different lenses or a different focal length (which by the way also affects depth of field). The point here supposedly is to check if a lens performs differently depending on the sensor, not vice versa. And to do that you need to be rigorous (or get "some nerdy numbers matching" as you call it), which is what Tony is trying to do but failing at.

[@jerzypietak5291]

So if I have got it right You blowed up smaller sensor and full frame one to match them up. That would mean your magnification for dx sensor is much higher than FF ONE. Or You compared them with 100 % enlargement each?

[@chrischan5168]

Jerzy Pietak yeah looks more like he ended up comparing sensors more than the effects of glass.

[@bharatadhikari4136]

Never buy dx lenses if you intend to go full frame in future. I have nikon d7200 and have FX lenses except the crappy kit lens. I love the result.

[@othomsen1]

If I take my full frame sensor out of my camera and with a knife cut it down to a APS-C and put it in the camera again. Did a FX lens suddenly get worser than a DX lens??

[@MrYankee853]

very nice analogy !

[@othomsen1]

Dan Ausec 😊👍

[@dxb526]

Shouldn't this be done using crop mode on FF instead zooming in?

[@AdrianGalli]

This is mostly nonsense. Changing the focal length has already skewed the results. No need to continue watching.

[@chosenideahandle]

Ya, it was a goofy move.

[@joeaddison]

What's the better solution then?

[@AdrianGalli]

@joeaddison Use a prime lens. It is foregone conclusion that zoom lenses do not maintain the same resolution at all focal lengths. Novice mistake. In the end, by virtue of the laws of physics, changing what is behind a lens does not affect the output qualities (resolution, for example) of said lens.

[@scotthullinger4684]

The resolving power of a lens has NOTHING to do with which camera body it was meant to be mounted on, a full frame body, or a crop sensor body. So Tony is WRONG. He's improperly explaining a concept, saying a certain thing is accomplished for such and such reason. He said you can get sharper results attaching a DX lens to a full frame body, which is ridiculous. Here is a way in which a full frame lens is GREAT on a DX format camera: The portion of the glass elements which is used for creating the image on a DX sensor is the more central portion, rather than towards the outer edge of the element. This means that the worst part of the lens is not even being used, simply because it is NOT revealed by the smaller sensor. This is why a 50 mm lens used on a DX sensor will produce an image as if you were using a 75mm lens. In other words, you get what seems to be a telephoto effect. The image circle, as they say, is going to be much smaller. So you get the "sweetest" portion of the lens creating your image.

[@meanmarine24]

I've been thinking this as well. Yes, a APS-C sensors throws away a big part of the FF image, but that part is towards the edge where defocus and CA is more appearent. Ignoring cost and weight, that should be an advantage.

[@jariol]

The difference is so small you're practically pixel peeping. Any difference you point out is swallowed by the skill or lack there of from the photographer

[@samhardy2479]

jariol thank you

[@robertturnip7850]

That's true, but he did mention that the results are purely academic.

[@dericsanchez4081]

If you have to zoom in 4x to see the smallest difference, it doesn’t matter. That is just nitpicking.

[@starry_lis]

Well, my reason is: I'm dirt poor. I shoot for pleasure, not as a career, too. I stuck a trusty Helios on any cheap dslr and that's just good enough :/

[@Filtersloth]

The same lens is not sharper on a full frame or cropped sensor. Exactly the same image comes out of the back of the lens regardless. It’s the same sharpness at the same focal length on full frame or aps-c, one of them is just cropped. It’s as simple as that.

[@user-wi7vu5hv8g]

hallelujah

[@marcdevries9027]

Sorry but you are wrong. The lens is indeed not sharper on full frame or crop. The same image comes out of the lens. But you capture a smaller part of the image with the crop lens. And then you ENLARGE it more so that it has the same picture size as the ff picture. When you take a picture with a crop sensor, you do not display it at a smaller size than a picture taken with a full sensor! That is where everybody always goes wrong in discussion about FF vs crop. It's really simple. Suppose the lens produces a image with a detail level of 1500x1500 dots. The FF sensor captures all that detail. But the crop sensor captures only 1000x1000 dots. Then you show both pictures full screen on your display. Tada! the picture with the same lens shows more detail with the FF sensor.

[@Filtersloth]

Marc De Vries thats a completely different problem and you are assuming that the full frame sensor has a higher megapixel count than the cropped sensor, which isnt always the case. Canon’s flagship camera the 1Dx MkIII has a full frame sensor with 21 megapixels, while Fujifilm’s X-T3 has a cropped APSC sensor with 26 megapixels, so the Fujifilm has a much higher pixel density. So if you cropped the full frame image so that both pictures showed the same section that comes out of the lens, in this case the image from the full frame camera would be much blurrier. Even in your own arbitrary example of 1500 dots vs 1000 dots you’ve done it wrong. To get the same image you wouldn’t blow up the cropped sensor image, you would have to crop the full frame image, so that it shows the same FOV. Then the images would be exactly the same. You are inventing a process that doesn’t make sense and also forgetting that sensors have different pixel densities.

[@marcdevries9027]

@@Filtersloth NO! I did NOT talk about the megapixel count of the sensor. The resolution example I talked about is the RESOLVING POWER of the LENS! It seems that a lot of people don't realize that there is a limit to the amount of detail a lens can resolve. That is why at 100% view an image will be soft. You are looking at a magnification higher than the resolving power of the lens. All current sensors have resolutions higher than the resolving powers of the lenses. That's why I took 1500x1500 as example. A current FF or crop camera can easily capture all that detail. The sensor is not the limiting factor. The LENS is the limiting factor. That is why the high pixel density of the crop sensor does not help. When you already have captured all the detail the lens can resolve, it does not help to have even higher pixel density as there is no extra detail to capture. Thus: as the total amount of image information in the image circle is limited, that means that you get less image information if you only use part of the image circle. Which means you get less image information. (lower sharpness) if you display both images at the same size. (And yes, for equivalent images you need to change the focal length. So either uses two primes of the same quality or a high-end zoom to do that comparison) I think the reason why people get this wrong, is because it is different for birders. Those extremely big, heavy and expensive lenses have incredible resolving power. In THAT situation a higher pixel density still helps in capturing more detail. But most people don't use lenses that cost $20000.

[@Filtersloth]

Marc De Vries ok then why are they now releasing sensors with 60 or 100 megapixels? I suppose the images from those cameras wont have more detail? If ‘everybody’ gets this wrong, has it occurred to you that you might be the one that’s confused? Because I’m certainly not confused about it and I’m not the one that keeps having to insert new variables into the argument to be correct, and change the original premise away from ‘are full frame lenses less sharp on cropped sensors’.

[@xedarkrunner5167]

With photography you should honestly look long term. If you plan to upgrade to full frame, you should stop buying apsc lenses for your crop camera immediately. Get an adapter and start building a lens collection before getting the full frame body. I'm heading towards a R6 mk2, and just put a EF 16-35 2.8L II lens on my m50, and they match perfectly. And will give me benefits on both crop and FF

[@Chris-NZ]

That was the route I went way back in 2005 with my 20D , taking it a step further I only got L glass. Sure overkill for a few years but not when I got my 5D2 😀, Buy good and by once.

[@ekill1395]

The premise of your video is flawed. You shouldn't be comparing crop sensor cameras and full frame cameras with full frame lenses and adjusting for field of view. There are a number of issues with the video. You say that since an aps-c camera is capturing less than half of the image produced by the lens, a full frame camera captures more than 2x the detail. Well, you forget that lenses are round. Camera sensors are rectangular. Even a full frame sensor is not capturing anywhere close to the full image produced by the lens. Also, a fairer comparison would be aps-c lenses on an aps-c sensor vs full frame lenses on an aps-c sensor. There is absolutely no reason to choose aps-c lenses over full frame lenses on the basis of image quality, except in particular case by case examples. The comparison you made is just dumb. All you're comparing is essentially the image quality of the camera. Most of the time, iq is going to be better from a full frame camera than an aps-c, so when you change the framing so that the camera captures the same fov, you're really just testing the camera body, not the combination of body and lens. All this video is saying is full frame cameras capture more detail. However, you're forgetting the main reasons people use full frame lenses on aps-c cameras. I see two main reasons. One, full frame cameras are a lot more expensive, typically, so someone starting out would buy a crop sensor camera. When they upgrade, an easy way to improve photo quality is to get better lenses. If they think they may get a full frame camera down the road, it makes complete sense to get full frame lenses. They will perform just as well as, if not better than, aps-c lenses on their aps-c camera. Then, when they upgrade to full frame, they don't have to buy all new lenses. Another big reason is that they need more reach. Now, with newer extremely high megapixel cameras coming out, this may not be as prevalent as it once was, but even with a 36mp D800, the 20.9mp D500 has greater pixel density. With wildlife photography in particular, a lot of the time, you can't get close enough to the subject and have to crop. Let's say for example that you are photographing a cardinal. Everytime you get close it flies a little farther away. You finally found a spot that means you're not too far away, and it won't fly away. Let's also say you have a D800 and a D500, that's my personal setup, so it is what I'm familiar with. Now, let's say just for the sake of this example that you are using a 500 f4. You have it mounted to a tripod and all you change between shots is what camera is on the back of the lens. You take one shot with the D800 and one with the D500. Even with the added reach from the crop sensor of the d500, you're not quite as close as you would like. So, you will crop both photos to the exact same fov. Well, the D800 used in DX mode captures about a 16 mp photo. As such, since you'll be cropping past that point, you'll have less than that. With the D500's DX sensor, you have 20.9 mp, so even though you won't end up with that, as you are cropping some, you will end up with more than the D800. Now, a D850 may have more pixel density than a D500, but it's also twice the price. A lot of wildlife photographers shot on crop sensors because it would give them more reach. Now, a lot do it because you can get a lot more reach for the money. Sure, when you adjust the frame to get the same fov, a full frame camera is typically going to perform better than a crop sensor, but that comparison is nonsensical because that defeats the purpose of a crop sensor.

[@ramonarias1234]

amen!

[@samozeal9466]

Good points. Bad attitude.

[@ekill1395]

@@samozeal9466 well, I posted that comment 2 years ago, so I don't remember my attitude at the time, but what makes you say that?

[@samozeal9466]

@@ekill1395 well it felt full of criticism and empty of grace. Felt like an attack on him with comments like "flawed" and "dumb". I feel you had good points that could have been presented in an uplifting way and not a "this is the internet so I can call you dumb even though I wouldn't face to face" kind of way.

[@ekill1395]

@@samozeal9466 well, like I said, I don't remember my attitude at the time of writing, and you have a point on the word dumb. That said, saying something is flawed is not attacking anyone or being overly critical. I'm sure I was being critical, to an extent, because I think it is bad advice that will end up costing people a lot of money and/or give them worse image quality.

[@waveland]

A poorly conceived and highly misleading comparison Tony. Changing the focal length to create an “equivalent” field of view, automatically means you’re not comparing the same optical rendering out the back of the lens. I don’t know that particular lens, but it could easily be softer at a wider field of view. It also means that the full frame image is 10mm more magnified in the center compared with the cropped sensor image, which almost certainly means the rendering of an object a few feet away will appear clearer and more detailed. Beyond that, what are the differences with the sensors themselves? Do they have the same photo site pitch? Does the more expensive camera have better internals that affect the quality of the captured image? Are there differing approaches to antialiasing on the two sensors? Do the two cameras approach sharpening and other in-camera processing differently? Are the photo sites smaller on the APS-C lens, meaning at any given exposure the sensor is having to apply more gain (which means more image noise) to capture an image at that exposure? I have enjoyed and learned a great deal from some of your technical videos, but this one probably needs to be deleted. The image circle is the image circle. If you grab a third of it with a crop sensor, or a half with a full frame, or three-quarters (with vignetting) using a medium format sensor, IF the sensors themselves are equivalent at the photo site level, then the center rendering in post processing will be exactly the same at the same focal length, only the overall field of view will differ. But if you attempt to equalize the field of view like you have done here, then quite obviously none of the three renders will have an equivalent output because you’re viewing the subject matter differently, and, you are by definition reconfiguring the optical properties of the lens. No reliable comparison can be made under those circumstances.

[@nilanjan160]

Excellent response!

[@PaulKretz]

I agree with theoretical base, but in practice I would say it all depends on the particular lens. Sometimes they're (FF vs APS-C) equal, sometimes any part wins.

[@johngrant765]

Isn’t the point to gain the additional reach by using a full frame lens on a aps-c?

[@michaelbowles420]

I use apsc cameras with full frame lenes and nobody notices. The average person isn't going to check the camera and lens combination . They just want the good results.

[@bmwslk230]

Nonsense from the beginning to the end. In this "experiment" different cameras, with different sensors, with different pixel-pitches and different image processing are compared. Let's think about this: The lens is mounted in front of a focusing screen (not on a camera) and you focus the image that is projected by the lens so that you get a sharp image on the screen. Now, put a 35mm slide frame behind the screen and "crop" the circle of projection to a full-frame image. Is the image going to be less sharp? NO! Now, take a frame in the size of an APS-C Sensor. Does it change the image? Will it become softer? NO! You can not change physics by image cropping.

[@luv2machine]

I'm so glad you addressed the issue about shooting wildlife. This should be a video all on it's own so us bird photographers don't spend extra money. I shoot mostly small birds and used crop sensors for years. I recently upgraded because of all the hype and feeling like I'm missing out by not shooting full frame. What a disappointment the first few days shooting in good light and comparing heavy cropped images against my crop sensor. I was expecting incredible detail from my new A7III camera. Unfortunately they were equal or worse than my crop sensor images. Of course features, focusing, and low light are amazing but I couldn't understand where's the detail?? Now I understand! Wish I watched the whole video when it first came out.

[@charlesjames9783]

Did you factor in the megapixel comparison of the crop vs. FF? The crop should look better if it has more MP on the subject. A large MP full frame camera should show an image improvement if it has more MPs on the subject.

[@MrAidit]

So using speed booster will make ff lens on apsc body better than using ff lens straight forward?

[@DeVere80134]

A FF lens will spit out the same image circle regardless of camera body type; you have not explained why the portion of that same image circle captured by the smaller aps-c sensor will be less sharp than on the FF sensor. Please explain how the quality of the image circle is different from one camera type to the next. You are comparing sensors and not lenses.

[@joeaddison]

Lenses have a max amount of detail they can output. The crop is taking that information only from the center and throwing the rest away. I can explain more if you need.

[@HelloFellowDinosaurs]

@@joeaddison You're spot on. The same way, if you crop in a full frame, it'll look lower quality than if it was zoomed out. I'm pretty sure, camera sensors are actually restricted by lens 99% of the time. A 75mp sensor would need insane glass to be able to utilize it's full potential, the lens would suffer diffraction and softness way before the sensor does, even on top of the line lenses.

[@DeVere80134]

Joe Addison - please do. Your comment does not address my point that Tony is not comparing lenses, he’s comparing sensors because the lens circle of projection is of the same quality regardless of what body it is on. The only difference is the amount that overlays the sensor. The cropped out portion is simply the cropped out portion, you are not losing any detail for the circle of projection that overlays the sensor.

[@r_v_g]

The problem must be the sensor. That's the only logical explanation. The output of a lens does not change, no matter what camera.

[@marcdevries9027]

Yes, the issue is the sensor. One is twice the size as the other and thus captures twice as much information.

[@HelloFellowDinosaurs]

@@marcdevries9027 Bigger pixels matter. A 10MP Full frame sensor would be better than a 24mp full frame sensor in low light, due to lower pixel density. The bigger each pixel, the better it's ability to capture more light, having more pixels at a smaller size, gives you less overall light.

[@joeshmoe7967]

@@marcdevries9027 I would jump in but I have seen your previous comments, and know better than to engage someone who does not understand there is no such thing as 'capturing half the detail the lens can capture'......

[@nightryder21]

Is he still messing up crop factor?

[@TonyAndChelsea]

please check out sdp.io/crop and tell me specifically what i'm messing up.

[@chrisklugh]

Are we not splitting a hair here. I would consider the long term use/value of a lens over the minimum differences in performance mentioned here. Make content, stop pixel peeping.

[@chosenideahandle]

This for those who want to know. I don't think Tony is at all a proponent of pixel peeping, but more interested in dispelling myths. You've read the title of this video before watching, so clearly something here was of interest.

[@chrisklugh]

@@chosenideahandle I agree. I did 'like' the video.

[@MchalesNavy]

There's definitely some exceptions to this. My personal experience has been, if you're shooting with cheaper lenses, kit lenses or even something more expensive, but still aps-c, and then switch to a pro-level lens, the results can be significantly better. My example here is going from a tamron 16-300 to a canon 70-200 IS on a canon 70 and 80d. The images from the 70-200 were significantly and repeatably better. Granted the two lenses can't take equivalent images across the range, but inside the ranges where they can compete, the 70-200 was just better, sharper, cleaner. Guess there's just a point where the full frame lens really is that much better than the apsc lens.

[@gamebuster800]

the answer i want to know: Is a good FF lens sharper than a cheaper APS-C lens? Edit: ah, 7:55, I was impatient, I'm sorry.

[@RedBullishTrading]

Is it simply because the crop bodies essentially magnify the imperfections in the glass where you on a fill frame body you wouldn’t necessarily see these imperfections until you crop?

[@s87343jim]

Yes, pretty much.

[@TonyAndChelsea]

yeah, ASP-C bodies produce higher magnifications. You're basically blowing up a smaller part of the lens.

[@tonylouisvisionvideography3469]

@@TonyAndChelsea What about FF Lenses on a Panasonic GH5s?

[@fernank017]

@@TonyAndChelsea but if you treat the APS-C + FF lens like an actual crop, IE comparing the full image of the APSC-FF combo to a 1.6x crop of FF+FF image, shouldn't the APSC+FF combo be sharper? Doesn't it come down to pixel density at that point?

[@s87343jim]

@@fernank017It depends. If you use a same lens(let's say 50mm FF lens), then put it on a 36MP FF body then do a APS-C crop. The result will be the same as that lens on a 16MP APS-C camera. So that's with the sensors with the same pixels per area. However, if the total pixel count the same for both cameras then the APS-C will appear to look worse. If the lens has infinite resolution power, then the result will be the same for both system. FF lens doesn't magically become worse on an APS-C camera body.

[@nerys71]

So. I have a Canon 6D and 7D. I have some decent glass for them. 70-200L II, sigma 15mm 2.8, older 28-70L 2.8, a 50mm f2.5 with lifesize adaptor, sigma 150-600 contemporary and I am trying to get a sigma 150mm 2.8 macro contemporary but grrr expensive :-) I just bought a 5Ds and will sell one of the other bodies. I was going to sell the 6D and keep the 7D so I can have both a crop and a FF but its seems from this I might be better off keeping the 6D for the FF benefits and better IQ with FF Glass. Does that sound logical to you? suggestions?

[@ToxicGopher]

I'm a photography geek so I get this but objectively, the situation is absurdly complex especially for consumer products.

[@andreistre7336]

what are your thoughts on using focal reducer/speed booster while running FF lenses on a crop?

[@burkholdst.rudderberg3574]

There is nothing sacred about "Full Frame"; it is just digital 35mm! Back in the day, when we spent all our hours in the Dark Room, 35mm was considered a SMALL format. As far a lenses go the rule of thumb is: If it fits, and you have a use for it, USE IT ( and if it doesn't fit, use an adapter) !

[@cooloox]

That wasn't a very smart post. FF generally gives MUCH cleaner images at high ISOs than crop sensor cameras. That's a fact, not an opinion. That one trait alone makes it superior. ISO noise is the one thing which manufacturers just haven't been able to overcome (yet). All APS-C cameras give noticeably noisy images at ISO 6400 and above. Modern FF cameras are much much cleaner. If you shoot wildlife and don't want to spend a fortune on long lenses then APS-C is a big advantage, except, you still get that crappy noise if shooting in anything less than ideal light conditions.

[@burkholdst.rudderberg3574]

@@cooloox So in other words, I should sell my Medium Format Hasselblad 500C/M camera and buy a digital 35mm"Full Frame"so I can get the superior, much much cleaner image ? As I did not mention APS-C cameras at all, perhaps your post was the one that was not very smart!

[@JasonMilner]

Another point to consider here is the fit of focal length ranges with sensor size. I bought an EF 24-105 f/4L for my APS-C Canon as an upgrade to the EF-S 18-55 kit lens, and a stepping stone towards my then ambition to eventually go FF. Yes it was a "better" lens, but I was constantly frustrated by the lack of a wide enough angle. 24mm on a crop body is not very wide at all, & having that 18mm had made a lot of difference. I eventually bought the EF-S 17-55 f2.8. It was a big improvement on the 18-55 kit lens, and had a far more useful range than the 24-105.

[@user-qj2wb7ne4e]

Absolute BS

[@danestead84]

Hi Tony, is the loss of sharpness by putting a FF lens on a crop body caused by the increased pixel density? If you cropped the centre portion out of an image taken with the a7r4 and compared it with an image taken by a crop camera (eg a6600) and used the same lens, would you expect very similar results due to similar pixel density? The AA filter may make a difference but that difference aside, would you think the results would be the same?

[@ricci.hidalgo]

I used for some few years a 70 - 200 f2.8 IS II Canon lens on Canon 7D and 7DMII APS-C crop bodies and results were impressively superb. Even comparable to the same lens on my full frame EOS R in spite of the higher sensor resolution.

[@Whoreshoer]

You HAVE to be kidding....This is HOGWASH.

[@Spiritbro77]

Complete nonsense. This isn't even remotely true.

[@lildevilgamer]

Unless you provide test results that contradict this test results this is just an opinion. Doesn't have to be your test results but provide something to back your statement up.

[@davidellinsworth22]

@@lildevilgamer he changes focal length and sensor in the same test.... that's two variables. It's an unscientific test, period.

[@Mosesybanez]

Full frame have larger sensors there usually gonna get a better image either way. So I kinda agree most of this testing is nonsense

[@gonmax]

The light that reaches the sensor in the apsc and the same portion of light that reaches the fx sensor is the same, and know what, its the sensor physical characteristics and software behind what defines the capability to represent that data as an image. The question is if that ff lens performs better or worse than the equivalent in apsc lens. Hint: IT DOESN'T.

[@23rdsentry72]

I’m pretty sure the pixel distance also plays a role in this. The smaller aps-c sensors usually have the pixels closer together, I think like 4nm apart, similar to the 61mp A7r iv, which ties in to the other concepts you mentioned.

[@touristguy87]

You have to take pixel pitch and total pixel count into account, to determine the pixel edge spacing, and you can always take that out of the equation (as you should) when comparing subfames to full-frames with the same lens. otherwise you run into the generic problem of putting an average subframe behind the lens, taking shots, then putting a good fullframe (with better AF and IP) behind the lens, taking similar shots, and comparing the results, and then generalizing about putting FF cameras behind FF lenses instead of subframes behind FF lenses. The point is that what may be true for a particular combination of lenses and bodies is not therefore inherently true for all combinations of lenses and bodies.

[@Design475]

At 9:52 you mention canon not having other options with the mirrorless system. What kind of results would a viltrox speedbooster yield using a ff lens on an m50 efm body??? Would it be worth it?

[@jorgemendez4517]

I use my 50mm F1.8 on my apsc and its GREAT

[@christianentertainmentoutdoors]

Thank you. I shoot 10 mp Canon 40D with 300mm crop lens for wildlife. I often need to crop. I was worried about that with the low megapixels of the camera to start with, but now I know if I an conservative on cropping it will most likely do little to no harm.

[@CShivery]

With all due respect, your methodology on determining pixel size is completely wrong and you should retract the part of your video that is inaccurate or misleading. What you should be doing is comparing the results of two lenses, an APS-C and full frame, both with the same FOV and millimeter size, on the same camera. Comparing a 20mm on a crop sensor to a 30mm on a full frame might sound like a good idea, but you're not comparing two lenses, you're comparing Lens A + Camera A against Lens B + Camera B with the assumption that any differences will be due solely to the lens, which patently is not the case. This is poor reasoning, and would be tossed on its backside if you were presenting it for peer review. Although KZbin doesn't hold you to the same standards as Academia, it is misleading to your loyal audience, who may not recognize the inaccuracies of your methodology. I for one was disappointed to see that part of your video.

[@TonyAndChelsea]

I have an entire section of the video where I discuss why that approach is the only approach that resembles real-world usage. And I do compare APS-C and FF lenses at the same FOV and MM size on the same camera. I literally do that.

[@jerzypietak5291]

So one more suggestion (if Ican). Unfortunately I don"t have NIKON D 850, but if I had ,here is what I would do: As far as I know D 850 and d 500 have the same pixel density except that of the d 500 is basically cropped d 850 sensor.(I might be wrong but if so, find another maybe Sony which have that reliations ). Now I would set up target in one place possibly close enough so I could use a flash to achieve maximum consistency of condition. Now I would position my let say d 850 and take a shot , than switch to d 500 with the same ff lens, take a shot. If what I stated about a sensor is true , then first I would crop d 850 to exact size of d 500 sensor. That would mean , i would have the same very similar sensor size ( APSC OF D 500 AND CROPPED NOT ENLARGED YET OF D 850!) I would proceed than with both to enlarge to 100%. Now you can compare same lens, same density sensor. Now I do not know what would the outcome be, but that would be more convincing to me. I write this not to criticize anybody I am just curious and that is it. Personally I use APSC camera completely happy with a results. There is way more to picture than pixel pipping. Also I am not against evaluating super sharp lenses, but when I see how much money you have to spend for ( according my judgement very little improvement in sharpness) I do want to LOL. Obviously there is that ( 1%) on top which need the best ,but those guys are not looking for advise on you tube they know exactly what to buy , where and how for specific tasks. That is only my small point of view, which probably many will disagree with . Well that is it. I am coming back for real education from masters of photography I like to learn.

[@iyzyz]

Misleading garbage.

[@mrkangfu]

Lots of accurate statements, but the takeaway is misleading. The sharpness of a lens is basically how much detail it can resolve. This is independent of the body or the sensor size that is attached. As others have mentioned, the picture from a crop body may appear to be less sharp, but this only because the pixel density is usually higher, thus revealing any imperfections in the lens. Here's another way to think about it. Take a picture with a Sony full frame camera and lens. Now take the exact same picture, but in APS-C mode. Your field of view would change, and your megapixels would drop, but you wouldn't say that the first picture is more or less sharp than the second picture. The second picture is basically just a crop of the first picture. Your second point is a bit more revelatory, however. A full frame lens on a crop body may perform worse than a crop lens on a crop body. My explanation is that the manufacturer expects the full frame lens to be paired with a full frame sensor, with lower pixel density than a crop sensor. Thus their target for resolving power can be lower than if they were manufacturing a crop lens.

[@KznnyL]

This was fantastic and answered many questions as I struggle to pick from a A7rii vs a6500.

[@cooper9917]

I was in a wedding where the second photographer was using a Canon 5Dmk4 with a Sigma 18-35mm f1.8 (for crop sensor), and she didn't understand why the corners were so dark when at wider focal lengths; she said they came out fine when corrected in Lightroom. I get so frustrated at these kinds of people. If you are going to claim to be a professional, at least know the tools of the trade. You don't have to be an expert, but at least know the basics.

[@davidho2977]

LOL!

[@AgnostosGnostos]

Larger sensors offer less high ISO noise and shallower depth of field. These are facts. Both these are very important for amateurs and professionals. Lenses for larger sensors aren't necessarily sharper or brighter than lenses for smaller sensors. The truth is that most lenses of high optical quality with reasonable prices are made for full frame cameras. Theses lenses can used on APS-C cameras with good results. Also in comparison to the variety of prime full frame lenses, the variety of Canon, Nikon, Sigma, Tamron prime APS-C lenses for dSLR cameras is very very poor. During the film era, full frame film and full frame lenses weren't always the best choice. Many professional photographers preferred medium format or large format film and lenses for sharper results and shallower depth of field. However the full frame film and full frame lenses at the end of film era became the norm for professionals and amateurs. APS-C film appeared very late during the start of the digital photography without real success. So full frame lenses continued to be very important during the digital era and still are. With the recent mirrorless revolution Sony and Fujifilm have introduced a significant good variety of prime APS-C lenses. APS-C lenses aren't mostly zoom ones with mediocre quality.

[@Needacreate]

Sadly, in key parts of its message, a rehash of half-truths, myths, and outright nonsense peddled earlier, this time enhanced with some questionable-methodology "testing". Other than (usually) higher costs, more bulk and weight, there is no disadvantage to shooting FF lenses on APS-C sensor bodies whatsoever. Particularly, there is no optical disadvantage that would negatively affect your image output. All digital sensors on this planet only ever use a crop of the image circle projected onto them. So, if anything, with a FF lens on a crop body, you're using the part of the image circle where the lens is at its best, namely the centre of it. I have shot Pentax APS-C DSLRs for a decade, and some of the highest-IQ lenses that you can put on those bodies are actually FF lenses. At the same time, Ricoh makes arguably one of the most diverse line-ups of dedicated APS-C lenses for these bodies. But their attractiveness does not lie in the fact that they would magically outperform their FF counterparts on the crop sensor, but rather in their more compact and lightweight designs (that take advantage of the size difference between FF and crop bodies) and more affordable prices. Bottom line: You may argue that, depending on the application, FF lenses on crop bodies can be a considerable waste of resources, but there is absolutely nothing "bad" about it. Why this BS is reiterated again and again like some weird conspiracy theory just blows my mind.

[@adamabele785]

Never had a problem with a f-f-lens on an apsc camera. The problem might come up, when you have some weak lenses, then you might see more of the flaws because of the higher resolution. Of course the full-frame camera performs better, that is the whole point of full-frame cameras, but this is a quality of the camera, not of the lens. Otherwise they would be a complete waste of resources.

[@j.k5654]

Very true, it has nothing to do with the lens but with the sensor.

[@touristguy87]

"Of course the full-frame camera performs better, that is the whole point of full-frame cameras, but this is a quality of the camera, not of the lens. Otherwise they would be a complete waste of resources." DING we have a winner! although he doesn't know how or why he won.... FF bodies pretty-much ARE a waste of resources compared to subframes for this very reason! You can't really isolate IQ differences to the BODY because the larger sensor "crops-in" more lens flaws than a subframe does. You put the same lens on a fullframe and now you have to worry more about the lens than you had to before as the lens simply will not perform the same when placed in front of a larger sensor at the same offset. And thus this entire video!

[@SmallSpoonBrigade]

My Canon 70-200mm F2.8L is absolute garbage on my 7D, but phenomenal on my 5D mk iv.

[@lalimalik6614]

@@SmallSpoonBrigade hi, why is it bad?

[@moritzmuessig]

I use a Sony aps-c camera. I am thinking about buying the Tamron 17-70 f2.8 APS-C lens or the Tamron 17-28 f2.8 Fullframe lens because i will upgrade to Fullframe in the future. Will there be a difference in depth of field?

[@ayhancapan]

Tony, just because of form factor, i think you should have changed the aperture also... When you was using the full frame lens on a6600 at the begining of the video... I mean... if you shoot f2.8 with full frame... Equivalent to APSC, aperture should be 2.0 on a6600 Am i wrong?

[@countbailiff3120]

I often wonder why photography enthusiasts worry so much about ultra sharpness, some of the most iconic photographs were produced decades ago, take a look at the Vietnamese children running for their lives, the image was captured with a film camera, its not that sharp and suffers from grain etc but it's an image any photographer would be proud to have captured

[@sleeplessgiant7407]

I can confirm for the sigma 1.8 zooms. I own both. The 18-35 has pretty random missed focus and the 50-100 is almost unusable due to missing focus constantly. Should have gone full frame :(

[@Lokix182]

I have these lenses also and my workaround has been just shooting in live view. It's kind of a pain, but in live view I have not had the same issues with the lenses missing focus.

[@sleeplessgiant7407]

@@Lokix182 I actually hadn't tried live view since it's usually not very good. I'm gonna give it a try, thanks ! :)

[@jsward96]

Yeah, I got the Sigma 18-35 for my D500, and was devastated to see so many of my images be completely back focused. Even after I got it calibrated, the outer AF fields are unusable. Really disappointing considering the main reason I got the D500 was because it's AF points covered more of the frame than Nikon's FX cameras. Still salty that practically *none* of the camera reviewing channels realised that this was an issue. I'm probably gonna sell the lens, though I am curious to see how it would perform on a Z mount camera with the F to Z adapter.

[@skylarkbonotto8051]

What microphone are you using ?

[@noplastik]

"Millions of photographers use full-frame lenses on their APS-C cameras". The world is full of mad photographers :D

[@SeanFisher]

Or broke people who use what they have or are given

[@LegionOf3]

Yeah I mean not all of us can go out and get an A7R III for $2,500 on top of another few grand in lenses.

[@ArnoldLamYT]

How do two lenses with the same technical specs compare AFTER considering the crop factor? eg, how would a f2.8 used on an APSC compare to a f4 used on a full frame?

[@yourtallness]

Each and every Christopher Frost video corroborates this as well.

[@GarryM66]

Mark Pitsilos I was thinking exactly the same 👍

[@cbflazaro]

except that he doesnt compare a lens at 2.8 on apsc with a lens at f4 on full frame. seems tony did that here because of his non sense "fstop equivalence"

[@marianksiazek7115]

well, not exactly, because 20MP FF and 20MP Crop sensor have very different pixel density, you would need to compare a 46MP FF to get a 20MP Crop sensor equivalent as far as pixel density goes... you would probably get the same results if you did it that way

[@VangelisMatosMedina]

Yes, especially the chromatic aberration test

[@JokingJay]

@@marianksiazek7115 He, i.e. Chris, essentially does this (at least to the extent it's feasible) by comparing lenses mounted to Sony FF cameras using their 42MP sensor vs. Sony APS-C cameras using their 24MP sensor. Not quite the perfect ratio, but close enough to make the point.

[@MattHalpain]

10-2021 I have a full frame Canon 5D Mark ii. I use full frame EF mount glass on my 5D Mark ii. I want to upgrade to a Canon M50 crop sensor camera and still use my EF mount glass on it. I've amassed some EF lenses and I don't want to have to re-buy glass that is native to the M50. I mainly shoot macro foliage and still life scenery. I think being cropped in on macro photos will not be so bad ?

[@Theforth09]

I love the one I am with: a6400 with 100-400mm gm for birds and other wildlife.

[@tinplater]

it seems to me that half the wildlife photo world use full frame lenses on crop sensor to achieve greater "effective" focal length. I doubt they would do this if they were producing inferior images.

[@GraphicMill]

Exception: What if you actually shoot the same lens at the same focal length and then compare image sharpness. Yes, the APSC sensor is going to be a tighter shot because of the crop, but that is one of the advantages of a crop sensor. I bet once you enlarge the FF image to match the cropped APSC image, the APSC is going to be sharper than the FF. It’s capturing that cropped area at full resolution where the FF will be lower resolution. .... I just noticed that you addressed this. I use my a7III FF lenses on my 6500 and for video they work great. I do have ‘wider’ APSC glass that are not available in FF. All in all, I love the higher resolution from the cropped APSC when I need that reach, yet using the 10-18mm f4 on the 6500 for a wide angle is not as nice as the 16-35 f4 on the a7III but it’s ideal for gimbal work. So, you live with it. :-).

[@CharlieMora]

Senor Tony, I have been waiting for your Review of the Canon 90D, but the camera has been out for months now, and have yet to see any mention of the 90D after you posted the Camera's announcement. The 90D with it's High Megapixel Sensor is having the same issues as the 5DS, where users are having to use Higher Shutter Speeds, and Lenses with Higher Resolving Power, to keep from getting soft pictures. When I saw the title for this video, I thought it would be a completely updated video from the original, and mention the 90D as the exception to the rule for FF Lenses on APS-C Bodies, but a lot all of the information is the same as the original video. The addition of more up to date camera models, and sample pictures to show the differences was great. Michael the Mavin, has been on the forefront with information on the 90D, and even recommends your book SDP in one of his first videos of the 90D. Michael has been doing a great job, but with you being one of the first KZbin'ers I followed when getting back in photography many years back, I love and respect your extremely analytical approach and am still waiting to see your Hands on Review of the 90D, and would Love to see you address and test the 90D issues with the Resolving power of lenses.

[@amermeleitor]

What about speedboosters? I will buy a Nikon Z50, Canon M50 II or Canon M6 II. I know there are adapters for EF and EF-S lenses, but there are speedboosters too, to get all the light from the EF lens, with AF and OIS. For Nikon there are adapters and speedboosters too.

[@nilofido411]

24MP FF vs 24MP A-PSC isn’t a like for like comparison

[@cooloox]

It's a perfect like-for-like example for this particular topic. A FF lens on a FF 24MP camera will use the full image circle (make best use of the optics of the lens) as intended by the manufacturer. The same lens on a 24MP aps-c camera will use far less of the image circle (use less of the glass) to still cover 24MP. So using less than half the lens to cover the same MP will clearly give a less detailed image. Keep in mind every lens only resolves a certain number of lines per mm of resolution. Going from FF to aps-c with the same lens is effectively asking the lens to resolve more detail out of less glass, which it cannot do, hence the resulting lesser detail.

[@nilofido411]

cooloox my point is that the comparison is flawed from its concept, too many variables, pixels pitch, AA filters, colour array filters, analog to digital converter... they are two different sensors, the only test that would have eliminated this variables hasn’t been carried, and that would have been to use the Sony A7R4 with both the 16-35 lenses and compare the apsc area of the images, then with the caveat of the sensor variables compare the image to the ones taken on a 24MP cropped sensor with the two lenses... Every lens has a peculiar line x millimetre resolution, as you rightly point out, however it is the sensor that changes, the lens is still the same, it won’t physically change irrelevant of what camera is mounted on; so if you use a lens designed for a 60MP FF on a cropped sensor that has 24MP it will perform better than a apsc lens designed for a 20MP apsc, or worse than an apsc lens designed for a 30MP sensor. With the exception of Fuji, camera manufacturers have stopped producing pro glass for apsc bodies more than a decade ago, when apsc were around 12MP, so even the old few pro apsc lenses are nowadays obsolete, whilst new kit lenses have a better line x millimetres resolution, still are kit lenses.... The second part of the video is more to the point, I would have started with the second part then use the images comparison to point out that in 2020 apsc users are facing being short changed by camera manufacturers...

[@lazic2856]

Yeah that was his point. He even pointed out that the ff24mp body is more like 10mp when its cropped and that's why its not as sharp. He is trying to make sure people understand what happens why they buy an entry level full frame and continue to use crop lens they are actually downgrading the image quality not upgrading.

[@actionphotopassion5082]

@@cooloox you said it. Using the FF lens on APSC means using less of that particular lens. Now what about this lens on a 40+Mpx FF sensor vs a 20+Mpx apsc sensor. On the APS-C sensor only the best part of the lens is used (=center) on the 40+Mpx FF sensor the corners will have less sharpness than the corners on the APSC image exactly because the APS-C is using the best part of the lens... The flaws of a lens are obviously more visible with the increase of Mpx of sensor. So that's why I agree that 24mpx FF vs 24Mpx APS-C isn't stressing enough to show that flaws of the inner lens properties.

[@reddonharper5195]

Let it go Tony. Enough.

[@Tophymaster]

I don´t care. I have used so many Full-frame lenses on the 70D and the results were superb!

[@joe_y.]

Cool, I don't care about your irrelevant anecdotal evidence.

[@cooloox]

@@joe_y. You're a bit arrogant and clearly missed the point. Tophymaster didn't disagree with Tony. By saying "I don't care", he actually acknowledged he realises he's getting a compromise, but doesn't care as he's getting great results anyway, even though the results would be better still with his lenses fitted to a FF camera. I have some FF lenses I use on aps-c bodies too and they're absolutely sharp and detailed. They'd be sharper on a FF camera, but without placing them side-by-side you'd never know!

[@Tophymaster]

@@cooloox Thank you for adding that to my comment.

[@edrader]

sure you're right. there's theory and then there is reality.

[@edrader]

there are always tradeoffs in photography and there's time when I choose crop over FF (reach).

[@jimm5593]

Bad method, bad theory. You are comparing different sensors, with different focal lengths and different apertures. Impossible to expect identical results.

[@vtkz]

I use the Samyang AF 35mm and the Sony 85mm 1.8 Fullframe Lenses on my 6400 and i`m realy impressed / satisfied from the sharpness and overall look, spec. for my photography style and use, theyre realy great. And i think after i compared it to my pictures with my previous apsc lenses, theyre a little bit better than (for exmple) my previous Sigma 60mm 2.8 APSC lense. I think its not a bad idea & money saver to buy and use FF lenses spec when you want to ,,upgrade,, someday to a Sony fullframe system. when you stay in the apsc sector i agree to buy apsc lenses and save money for the next photo travel ;- ) - at the end i`m happy with my 2x FF lenses that i bought a few months ago

[@oje101]

Hi. So am using a Canon R7 and with a couple of ef lenses.. so if I understand clearly am loosing quality by using ef lens on an apc.. I thought the only difference. Was that if I wanted to shoot wide .. say @ 24 I'd have to use a 15mm.. but I didn't know I was loosing quality.. see there are no 2.8 or faster lenses that are rfs.. would a speed booster help quality?