[wim]

[quote name='PuxaVida' timestamp='1288623630' post='3884']

Yes, but the effects of diffraction on the image depends on the sensor characteristics; like the size of the pixels, CoC and the diameter of the airy disk. The diffraction limited f-value is different in cropped sensor and FF sensor (given that they have the same MPs).[/quote]

This is actually an opinion, not truth. The guys who wrote this article have been proven wrong by others who weren't as publicized as these guys. If this stuff really was true, we would have seen exactly the same effects with film. Why did we never hear about this? Furthermore CoC and Airy disk are directly related, if not the same. it actually goes a little too far for me to have a discussion about this here, so I want to leave it at that, if you don't mind too much.



Diffraction only depends on aperture, nothing else.

By "equivalent" if you mean F=10@1,5x crop vs. F=15@FF, you're right. I have to correct myself here. Because,



1,5x crop, 50mm, 10 meters distance, F=10 have the same DoF in meters as in FF, 75mm, 10 meters distance, F=15. And at the same time F10 and F15 are diffraction limited f-values for 1,5x crop and FF sensor (given that they're both 12mp).

Nope. Diffraction limits for APS-C are around F/13 and around F/18 for FF. I'd work it out for you if I had the tools handy right now, but I don't. The only thing that differs is apparent resolution. That is what CoCs and Airy disks are about.



Furthermore, the DoF equivalent of F/10 on APS-C is a little over F/16 on FF.



Kind regards, Wim