IQ advantage of Aps-c vs cropping FF?

[Photografica]

Only talking image quality, is there an advantage of using an Aps-c camera over cropping a FF (with the same pixel density and everything else equal) to get more "reach"? Or will the result be identical?

 

[sybersitizen]

Only talking image quality, is there an advantage of using an Aps-c camera over cropping a FF (with the same pixel density and everything else equal) to get more "reach"?

No, not if the sensor technology is the same.

Or will the result be identical?

As close to identical as two results can be.

 

[FingerPainter]

If all else is equal , then you are using the same lens, so sharpness should be the same. However, if both sensors have the same pixel pitch, then the larger sensor has more pixels. This means the larger sensor will probably exhibit a fraction of a stop more read noise, especially at low exposures (high ISO).

 

[PHAER]

Only talking image quality, is there an advantage of using an Aps-c camera over cropping a FF (with the same pixel density and everything else equal) to get more "reach"? Or will the result be identical?

On good light, I'd say they will be very very similar. On worst light conditions, not really.

 

[FrancoD]

By equal, what is meant is pixels per duck. (birder term...)

What it means is that if after cropping the FF shot you still have the same amount of pixels you have in the APS one, yes the image will be (more or less) the same.

The problem is that if ,say, your FF has a 42MP sensor, the APS crops gives you 18MP, so in this case the 24MP APS version would be better.

If you start with a FF 24MP sensor, well you end up with 10MP....

 

[robert1955]

If all else is equal , then you are using the same lens, so sharpness should be the same. However, if both sensors have the same pixel pitch, then the larger sensor has more pixels.

In total yes. But the OP wants to use only a apsc sized crop from the FF. Which I think would result in almost identical images, especially since same brand of camera is implied

This means the larger sensor will probably exhibit a fraction of a stop more read noise, especially at low exposures (high ISO).

 

[FrancoD]

Only talking image quality, is there an advantage of using an Aps-c camera over cropping a FF (with the same pixel density and everything else equal) to get more "reach"? Or will the result be identical?

On good light, I'd say they will be very very similar. On worst light conditions, not really.

Have you seen samples of that ?

Say the 61 MP on APS crop (26 MP) versus the image taken by a 24 MP APS camera.

 

[robert1955]

By equal, what is meant is pixels per duck. (birder term...)

What it means is that if after cropping the FF shot you still have the same amount of pixels you have in the APS one, yes the image will be (more or less) the same.

The problem is that if ,say, your FF has a 42MP sensor, the APS crops gives you 18MP, so in this case the 24MP APS version would be better.

If you start with a FF 24MP sensor, well you end up with 10MP....

But for the sake of completeness, if you use cameras with the same pixel pitch, the FF would be about 61MP

 

[Rene Gr]

Only talking image quality, is there an advantage of using an Aps-c camera over cropping a FF (with the same pixel density and everything else equal) to get more "reach"? Or will the result be identical?

The FF lens will be computed to cover the FF sensor, while the APS-C lens is made for the smaller circle. I'd expect more sharpness in APS-C. But that is not necessarily so. Modern FF lenses are sharpest in the center, neglecting the corners when wide open.

 

[PHAER]

Only talking image quality, is there an advantage of using an Aps-c camera over cropping a FF (with the same pixel density and everything else equal) to get more "reach"? Or will the result be identical?

On good light, I'd say they will be very very similar. On worst light conditions, not really.

Have you seen samples of that ?

Say the 61 MP on APS crop (26 MP) versus the image taken by a 24 MP APS camera.

Not at that specific mp, but you can use the comparison tool on dpreview and, for example, compare the R7 (32mp) against the older R6 (20mp) and you will see that things are much more similar at iso 100 than at anything above iso 1600...

https://www.dpreview.com/reviews/im...1&x=-0.8343561368209256&y=-0.6424344885883349

It's possible to take the images, resize, and evaluate, but in terms of noise and color depth, I don't feel it's necessary to see that there is still some relevant difference.

 

[FrancoD]

What I was saying is that if ,for example, you use a 400mm on an APS camera and with that you fill the frame with a duck, when you use the same lens from the same distance on an FF camera and then crop to the APS size and enlarge both images (or print them) to the same size (say an 8"x12") you need to start with a 61MP FF to match a 24MP APS. If the FF is of the 42MP type, the 24MP APS will give a a more detailed duck.

What I am pointing out is that some may not realise just how many pixels you lose by cropping from FF to APS.

 

[PHAER]

What I was saying is that if ,for example, you use a 400mm on an APS camera and with that you fill the frame with a duck, when you use the same lens from the same distance on an FF camera and then crop to the APS size and enlarge both images (or print them) to the same size (say an 8"x12") you need to start with a 61MP FF to match a 24MP APS. If the FF is of the 42MP type, the 24MP APS will give a a more detailed duck.

What I am pointing out is that some may not realise just how many pixels you lose by cropping from FF to APS.

Yes, and you're right! But what I was pointing is that the size of the image/pixel count doesn't necessarily tell the quality of it!

On the example I gave before (32mp crop x 20mp FF), imo the smaller image of the FF has better quality than the 1,6x bigger image on the crop, at iso 6400, for example!

 

[robert1955]

What I was saying is that if ,for example, you use a 400mm on an APS camera and with that you fill the frame with a duck, when you use the same lens from the same distance on an FF camera and then crop to the APS size and enlarge both images (or print them) to the same size (say an 8"x12") you need to start with a 61MP FF to match a 24MP APS. If the FF is of the 42MP type, the 24MP APS will give a a more detailed duck.

What I am pointing out is that some may not realise just how many pixels you lose by cropping from FF to APS.

Yes, and you're right! But what I was pointing is that the size of the image/pixel count doesn't necessarily tell the quality of it!

On the example I gave before (32mp crop x 20mp FF), imo the smaller image of the FF has better quality than the 1,6x bigger image on the crop, at iso 6400, for example!

but you are introducing extra variables [different pixel pitch, not same generation, probably not same lense]. this discussion is far more limited

 

[PHAER]

What I was saying is that if ,for example, you use a 400mm on an APS camera and with that you fill the frame with a duck, when you use the same lens from the same distance on an FF camera and then crop to the APS size and enlarge both images (or print them) to the same size (say an 8"x12") you need to start with a 61MP FF to match a 24MP APS. If the FF is of the 42MP type, the 24MP APS will give a a more detailed duck.

What I am pointing out is that some may not realise just how many pixels you lose by cropping from FF to APS.

Yes, and you're right! But what I was pointing is that the size of the image/pixel count doesn't necessarily tell the quality of it!

On the example I gave before (32mp crop x 20mp FF), imo the smaller image of the FF has better quality than the 1,6x bigger image on the crop, at iso 6400, for example!

but you are introducing extra variables [different pixel pitch, not same generation, probably not same lense]. this discussion is far more limited

Yes, of course I included more to the discussion: Our colleague asked if the results would be the same in IQ. And image quality is not only about pixel count. Noise itself is something that vastly influences on the results in question! Otherwise, the discussion won't find much link to the real world, don't you think?

 

[robert1955]

What I was saying is that if ,for example, you use a 400mm on an APS camera and with that you fill the frame with a duck, when you use the same lens from the same distance on an FF camera and then crop to the APS size and enlarge both images (or print them) to the same size (say an 8"x12") you need to start with a 61MP FF to match a 24MP APS. If the FF is of the 42MP type, the 24MP APS will give a a more detailed duck.

What I am pointing out is that some may not realise just how many pixels you lose by cropping from FF to APS.

Yes, and you're right! But what I was pointing is that the size of the image/pixel count doesn't necessarily tell the quality of it!

On the example I gave before (32mp crop x 20mp FF), imo the smaller image of the FF has better quality than the 1,6x bigger image on the crop, at iso 6400, for example!

but you are introducing extra variables [different pixel pitch, not same generation, probably not same lense]. this discussion is far more limited

Yes, of course I included more to the discussion: Our colleague asked if the results would be the same in IQ. And image quality is not only about pixel count. Noise itself is something that vastly influences on the results in question! Otherwise, the discussion won't find much link to the real world, don't you think?

Wel, maybe the OP had a limited goal in mind. Your example does not address that. From your previous posts it was not clear that you wanted to change the subject. And that wider subject has been discussed so often that it could last you a lifetime

 

[FingerPainter]

Only talking image quality, is there an advantage of using an Aps-c camera over cropping a FF (with the same pixel density and everything else equal) to get more "reach"?

No, not if the sensor technology is the same.

Yes, precs9ley because the sensors tech is the same. The amount of read noise depends in part on the number of read operations. More pixel of the same tech then produce a larger total of read noise.

Or will the result be identical?

As close to identical as two results can be.

 

[bobn2]

Only talking image quality, is there an advantage of using an Aps-c camera over cropping a FF (with the same pixel density and everything else equal) to get more "reach"? Or will the result be identical?

There might be an advantage in using a particular APS-C camera over a particular FF camera, or the advantage might go the other way round. As a generalisation though, if the pixel size is the same then the APS-C and cropped FF will produce exactly the same result. This is particularly true because if the pixel size and tech (i.e, FSI vs BSI) is the same and the sensor manufacturer is the same, it's highly likely that the pixel design itself will be the same and thus work exactly the same way.

 

[tbcass]

Only talking image quality, is there an advantage of using an Aps-c camera over cropping a FF (with the same pixel density and everything else equal) to get more "reach"? Or will the result be identical?

As someone who has done both extensively I can say with confidence that the results are identical.

 

[tbcass]

If all else is equal , then you are using the same lens, so sharpness should be the same. However, if both sensors have the same pixel pitch, then the larger sensor has more pixels. This means the larger sensor will probably exhibit a fraction of a stop more read noise, especially at low exposures (high ISO).

Not true because pixel density is the same which was a qualifier mentioned by the OP. The cropped FF is the same as the APSC.

 

[tbcass]

Only talking image quality, is there an advantage of using an Aps-c camera over cropping a FF (with the same pixel density and everything else equal) to get more "reach"? Or will the result be identical?

On good light, I'd say they will be very very similar. On worst light conditions, not really.

Have you seen samples of that ?

Say the 61 MP on APS crop (26 MP) versus the image taken by a 24 MP APS camera.

Not at that specific mp, but you can use the comparison tool on dpreview and, for example, compare the R7 (32mp) against the older R6 (20mp) and you will see that things are much more similar at iso 100 than at anything above iso 1600...

https://www.dpreview.com/reviews/im...1&x=-0.8343561368209256&y=-0.6424344885883349

It's possible to take the images, resize, and evaluate, but in terms of noise and color depth, I don't feel it's necessary to see that there is still some relevant difference.

Unfortunately, that is not relevant because you are comparing 2 different sensors with different technologies.