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01-14-2015, 07:57 PM   #76
osv
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QuoteOriginally posted by aleonx3 Quote
No, I am afraid I don't agree with that statement you just made..."since ff is not as diffraction-limited as aps-c is".
you are right in the sense that when the dof is equal, there is an equal amount of diffraction, so there is no advantage either way, ff and crop both have the same amount of diffraction.

problem is, the smaller the sensor, the sooner diffraction kicks in... according to the article, f/8 on crop will show diffraction artifacting, while f/8 on ff does not.

QuoteOriginally posted by aleonx3 Quote
Isn't this contradict with the statement in that article - that diffraction has nothing to do with FF/APS-C/mFT, it is the lens property?
both articles state that lens design is a factor in diffraction artifacting, but the article with the picture did appear to take the lens property claim to an extreme.

take a look at it here, there is little mention of lens design as a significant factor in diffraction artifacting:

Diffraction Limited Photography: Pixel Size, Aperture and Airy Disks

01-14-2015, 10:41 PM   #77
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QuoteOriginally posted by normhead Quote
Diffraction doesn't change, but diffraction is pixel related. Diffraction on a smaller sensor with smaller pixels will have a greater effect. The difference between APS-c and FF is pretty small. The sizes in pixels size just aren't that dramatic. Other differences, like how a D3s can approach the lw/ph of a D800 is way more important. Compared to other discrepancies, really, don't even think about diffraction at current MP levels.
Diffraction - like so many other things - tends to get overrated in these debates. Differences are real, but after a while I begin to wonder how photography is even possible short of 35mm

OTOH I recently went through some of my cameras and lenses to test which combination would give me the best results at very long focal lengths - not in terms of equivalence but simply in terms of the gear I own. Strangely I achieved the optimum result with an ancient 135mm Sonnar stopped down to F/11 on a Pentax Q. Now theoretically 'everyone' knows that the Q is diffraction limited just about as soon as you stop down the lens but there it was: F/11 on the Q. Go figure.
01-15-2015, 03:57 AM   #78
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QuoteOriginally posted by osv Quote
you are right in the sense that when the dof is equal, there is an equal amount of diffraction, so there is no advantage either way, ff and crop both have the same amount of diffraction.

problem is, the smaller the sensor, the sooner diffraction kicks in... according to the article, f/8 on crop will show diffraction artifacting, while f/8 on ff does not.



both articles state that lens design is a factor in diffraction artifacting, but the article with the picture did appear to take the lens property claim to an extreme.

take a look at it here, there is little mention of lens design as a significant factor in diffraction artifacting:

Diffraction Limited Photography: Pixel Size, Aperture and Airy Disks
The diffraction calculator in the article you posted indicates that 16 megapixel APS-C is diffraction limited at f8 and 36 megapixel full frame is diffraction limited at f11. Those should give roughly equivalent depth of field (maybe a little more on APS-C).

In the end, diffraction is not a real issue. I have never shot a photo, printed it and then had folks complain because it was "softened" by diffraction. I certainly don't shoot at f22, but I have thrown away a bunch more photos because not enough of the image is in focus, than I have because there is too much diffraction.

This image was shot at f13. The stump was close enough that f8 and 11 did not give me adequate depth of field. Just the way that it is...

01-15-2015, 01:47 PM   #79
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QuoteOriginally posted by Rondec Quote

In the end, diffraction is not a real issue. I have never shot a photo, printed it and then had folks complain because it was "softened" by diffraction.
I tend to agree, I don't think diffraction deserves as much ink as it gets, and it's hard to justify giving up a desired DOF just to maximize sharpness when a lot of times that difference in sharpness isn't even very visible and things are still more than 'sharp enough'.

The only scenario where I think it really matters is maybe macro, where you're stuck because you want both maximum detail and maximum DOF at the same time... which is why the pros gravitate towards focus stacking there.

01-15-2015, 01:53 PM   #80
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i like that frozen lake shot, very nice... you are fighting field curvature there, and while it's so bad that it's overwhelming the diffraction issues, the high pixel density of the k3 is working to your advantage... i have the exact same problem on ff, with wide legacy glass; it's a nightmare, and i unfortunately don't have that high pixel density cushion.

the solution is to test and reject glass that has field curvature problems, so that we aren't forced to shoot at diffraction-limited apertures like f/13.
01-15-2015, 05:25 PM   #81
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QuoteOriginally posted by jsherman999 Quote
I tend to agree, I don't think diffraction deserves as much ink as it gets, and it's hard to justify giving up a desired DOF just to maximize sharpness when a lot of times that difference in sharpness isn't even very visible and things are still more than 'sharp enough'.

The only scenario where I think it really matters is maybe macro, where you're stuck because you want both maximum detail and maximum DOF at the same time... which is why the pros gravitate towards focus stacking there.
Focus stacking is a marvelous thing.

Last edited by GeneV; 01-15-2015 at 05:31 PM.
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