FF Sharper than crop?

[Marsu42]

We are not debating functionality but rather sharpness

But then you're missing the point of L lenses - they're not L because only they excel in sharpness, but as a combination of different factors ... if looking at sharpness alone, there are quite few L duds wide open uwa or older L lenses like 35L vs. newer 3rd party. The L glass is also supposed to have good color rendition which might be more important to some than test-chart pixel counting.

 

[CropFactor]

We are not debating functionality but rather sharpness

But then you're missing the point of L lenses - they're not L because only they excel in sharpness, but as a combination of different factors ... if looking at sharpness alone, there are quite few L duds wide open uwa or older L lenses like 35L vs. newer 3rd party. The L glass is also supposed to have good color rendition which might be more important to some than test-chart pixel counting.

The question is : FF Sharper than crop?

Answer : Yes it is. Bigger sensors capture more detail even when compared to a crop with the same MP.
(6D vs 70D = no contest, 6D wins)

Added : To get the most from an FF, stick an L on it. (Look, even non L primes are amazing)

Again ill say, the difference in sharpness between CR + L and CR + Non L is marginal at best.

So with everything said, if you have a cropped body and you want more detail in your photos, go for a FF body.

 

[CarlTN]

The formal answer is that with any lens detail contrast drops as resolution increases. This relationship is illustrated by the lens MTF curve. A lens has more contrast at 10 lpmm then at 20 lpmm. When you frame a scene onto a smaller sensor, the details occur at a higher lpmm frequency and therefore have less contrast.

However, at low to mid ISO it's a meaningless difference because the contrast can easily be restored in post processing, whether in a tool like Photoshop or in camera using the sharpness setting. Detail contrast is not an unlimited good, and at ISO 800 and below it's trivial to make an APS-C file as sharp as an optimally processed FF file. At high ISO FF has a true sharpness advantage because when you apply extra sharpening to the ASP-C file you emphasize noise that's not in the FF file.

+1, well said!

Full frame is generally sharper than crop, because the pixels are larger, thus the lens need not be as sharp to achieve a desired level of sharpness.

The link to the EF 200 f/2L comparison is interesting, because it is showing the border and corner resolution inferior on the 70D, to that of the 1Ds3, yet the center resolution appears identical. This alone should show you that the difference here, is that the 1Ds3's pixels are so much larger than the 70D's, that the lens's loss of "sharpness" towards the full frame borders, is hardly noticed by those larger pixels. Yet the 70D is finding the loss halfway to those borders, within its own..."crop circle"!

This is why I have said (and got pounced on for it), that a future 50+ MP full frame camera, is rarely if ever going to fully resolve detail on all of its pixels on most every lens there is (if not actually every one, even perhaps including the Zeiss Otus...especially if it's more like a 60+ MP full frame sensor). The reason being that you would see unbelievable softness at the pixel level, as you get closer to the full frame borders and corners (especially on even such a fine "big white" as the 200 f/2, shot wide open). I've rented this lens briefly, and I liked it more than every other lens I've tried or owned...so I am not biased against it whatsoever. I frankly feel it has the kind of color rendition that no other lens in the world has...almost everything about it was as close to perfect as I could ask for.

Here is one of my favorite images that I shot with it. It's not full size, because I try not to show those. Camera was the 50D.

 

[verysimplejason]

If you want real gain in sharpness, go with FF + L

L? It's also do-able on most primes.

 

[dtaylor]

The resolution of the lens used in the Crop sensor needed to have 1.5 time more resolution than the one used in the FF to give us the same sharpness.

This is false. Resolution and detail contrast (sharpness) are two related but separate things. The measured resolution difference (in lpmm) between FF and APS-C sensors of comparable pixel counts is small as good lenses still comfortably out resolve sensors at MTF10. Adding more pixels to the APS-C sensor would not alter the lens MTF curve. The loss of detail contrast happens in the lens, not on the sensor. (Assuming AA filters of equal strength.)

Read this :

I would rather watch paint dry then read DxO theories.

For the pixel peepers, it's rather worrying the amount of resolution lost in cropped systems.

DPReview measured the 5D2's resolution to 2800/3300 (absolute/extinction). The 7D was measured to 2500/3100. The difference is smaller then the difference in sensor pixel count. (So much for DxO theories.)

There is very little to gain by sticking an L lens on a crop body.

Apparently you've never actually tried this. FYI, I can see the difference out of camera between the 70-200 f/4L and 70-200 f/4L IS on a 7D. The difference between either L lens and a consumer zoom on the same body is quite large. (The L vs L differences probably wouldn't survive post processing, but the L vs non-L differences definitely would.)

For example you won't gain 8MP in overall resolution by jumping from a 12MP 450D to a 20MP 70D (crop of course).

You will gain exactly 8 MP because MP is a measure of the number of photo sites on the sensor. The fact that DxO plays fast and loose with definitions and creates meaningless ones like "perceptual megapixels" is the first indication that they are a pseudo-science site.

Your percentage gain in image lpmm will not be equal to the gain in MP because there are losses. But the losses are nearly identical for a 12-20 MP jump in the 35mm format.

Can we possibly say this :
Lets assume a 20MP crop canon here....
20/1.6 = 12.5
12.5 being the maximum MP you could possibly hope to get.

No we can't say that. Strictly speaking that is absurd because MP always refers to the number of photo sites on the sensor. I know what you are trying to say, but we can't say it even with correct terminology because all observations are to the contrary (see below).

Answer : Yes it is. Bigger sensors capture more detail even when compared to a crop with the same MP. (6D vs 70D = no contest, 6D wins)

Detail != sharpness.

For sharpness, I agree that a 6D will be sharper out of camera all other factors being equal. And I'll add that the difference will not survive post processing unless the images were made above ISO 800.

For detail, Imaging Resource has measured and published the resolutions of both, and they are nearly identical. 2400/3400 for the 6D and 2500/3200 for the 70D.

 

[dtaylor]

This is why I have said (and got pounced on for it), that a future 50+ MP full frame camera, is rarely if ever going to fully resolve detail on all of its pixels on most every lens there is...

I wouldn't "pounce" on you for this, but I would disagree. If we were to scale up current APS-C densities they would equal 45 MP or more on FF. The number of lenses and aperture combinations that yield excellent detail and sharpness on my 7D and M are quite large actually. Granted it's more challenging to hold that across the frame on 35mm, but I don't doubt that a 50 MP FF body would prove excellent with good glass and a tripod or IS. I think we would be looking at 75-100 MP before there would be hardly any lenses or apertures that benefit.

Here is one of my favorite images that I shot with it. It's not full size, because I try not to show those. Camera was the 50D.

Beautiful.

 

[ecka]

This is why I have said (and got pounced on for it), that a future 50+ MP full frame camera, is rarely if ever going to fully resolve detail on all of its pixels on most every lens there is...

I wouldn't "pounce" on you for this, but I would disagree. If we were to scale up current APS-C densities they would equal 45 MP or more on FF. The number of lenses and aperture combinations that yield excellent detail and sharpness on my 7D and M are quite large actually. Granted it's more challenging to hold that across the frame on 35mm, but I don't doubt that a 50 MP FF body would prove excellent with good glass and a tripod or IS. I think we would be looking at 75-100 MP before there would be hardly any lenses or apertures that benefit.

I think that "excellent detail and sharpness" is a matter of opinion. I thought my 7D+Sigma 50/1.4 was excellent, until I tried 5D2+50/1.8'II (I hated the build, pentagon aperture and AF noise, but it was SHARP!). FF wins thanks to either bigger pixels or more of them.

 

[jeffa4444]

Real estate will always win out why do people think fashion photographer shoot with medium format.

 

[dtaylor]

I think that "excellent detail and sharpness" is a matter of opinion. I thought my 7D+Sigma 50/1.4 was excellent, until I tried 5D2+50/1.8'II (I hated the build, pentagon aperture and AF noise, but it was SHARP!). FF wins thanks to either bigger pixels or more of them.

I'm going to be blunt because I've shot both combinations (owned both lenses at one time, now just the Sigma): at low ISO and wide apertures, if your final 7D+Sigma file doesn't look better then your final 5D2+NiftyFifty file something is wrong.

 

[ecka]

I think that "excellent detail and sharpness" is a matter of opinion. I thought my 7D+Sigma 50/1.4 was excellent, until I tried 5D2+50/1.8'II (I hated the build, pentagon aperture and AF noise, but it was SHARP!). FF wins thanks to either bigger pixels or more of them.

I'm going to be blunt because I've shot both combinations (owned both lenses at one time, now just the Sigma): at low ISO and wide apertures, if your final 7D+Sigma file doesn't look better then your final 5D2+NiftyFifty file something is wrong.

By SHARP! I mean f/2.8+ sharp . Sigma 50/1.4 produces much nicer bokeh (I think it is one of the best 50s), but I don't think it is sharper wide open on crop, than 50/1.8'II on FF. However, sometimes wide open images from 50/1.8'II are a bit dreamy with glowing high contrast edges.

 

[CarlTN]

This is why I have said (and got pounced on for it), that a future 50+ MP full frame camera, is rarely if ever going to fully resolve detail on all of its pixels on most every lens there is...

I wouldn't "pounce" on you for this, but I would disagree. If we were to scale up current APS-C densities they would equal 45 MP or more on FF. The number of lenses and aperture combinations that yield excellent detail and sharpness on my 7D and M are quite large actually. Granted it's more challenging to hold that across the frame on 35mm, but I don't doubt that a 50 MP FF body would prove excellent with good glass and a tripod or IS. I think we would be looking at 75-100 MP before there would be hardly any lenses or apertures that benefit.

Here is one of my favorite images that I shot with it. It's not full size, because I try not to show those. Camera was the 50D.

Beautiful.

Thanks very much! I still think I have to disagree with you though. There aren't that many lenses that are sharper than the 200 f/2L, but yet the 70D can't use but about half its pixels to resolve detail through it (at least when wide open at f/2). And the 70D is equal to the middle of about a 50 MP full frame's...frame. I'm not saying you couldn't appreciate the sharpness of the world's best lenses with such full frame sensors...it's just that you could only appreciate it in a small part of the center at wider apertures, and perhaps up to maybe 65% of the sensor area when closed to optimum arperture (especially if we go to 60+ MP).

When you discuss how sharp your results have been with an 18 MP crop sensor, you're forgetting just how much softer the lens becomes once you go larger than that sensor, it seems to me. Discussing the current 22MP 5D3 sensor, has nothing to do with what a 50MP sensor would look like on the same lens.

This surely is one reason why Canon has expressed interest in medium format. I suspect that 10 years from now, medium format will be what we are all using, or beginning to use. And full frame digital cameras will be priced like the Rebels of today (adjusted for inflation of course). But this assumes we will still have a currency, or even a civilization then, and there are no guarantees of that.