Diffraction Compensation:How to compensate for lost sharpness at small apertures

[Dinarius]

I found this article really interesting, and it was one of the reasons I was querying the other day how to put the same image side-by-side on the screen to compare the effect of sharpening.

However, unless I'm going blind, when I put two of my Canon files together on the screen (at 100%) and tick the Diffraction Compensation box for one of them, I can see no change in sharpness.

Does this C1 feature only work with PhaseOne files?

Thanks.

D.

[Bart_van_der_Wolf]

I found this article really interesting, and it was one of the reasons I was querying the other day how to put the same image side-by-side on the screen to compare the effect of sharpening.

However, unless I'm going blind, when I put two of my Canon files together on the screen (at 100%) and tick the Diffraction Compensation box for one of them, I can see no change in sharpness.

Does this C1 feature only work with PhaseOne files?

Hi,

No, it works on all Raw (!) images. However, it targets diffraction only, not defocus. Therefore, it is most effective in the plane of best focus, not so much at the edges of the DOF zone.

Cheers,
Bart

[Dinarius]

Hi Bart,

Thanks for the reply.

Yes, of course I was comparing RAW files, but obviously not the kind that would show a difference.

Will try again.

Good to know it will work with my Canon, in any case. It's a really neat addition to C1.

Would be interested to hear people's views on noise and Diffraction Compensation.

Cheers!

D.

[Dave Ellis]

I found this article really interesting, and it was one of the reasons I was querying the other day how to put the same image side-by-side on the screen to compare the effect of sharpening.

However, unless I'm going blind, when I put two of my Canon files together on the screen (at 100%) and tick the Diffraction Compensation box for one of them, I can see no change in sharpness.

Does this C1 feature only work with PhaseOne files?

Thanks.

D.

Hi D

I'd suggest you take a raw shot of something like a Siemens test chart initially with an f stop of f/22. Zero out the default sharpening in C1 and then toggle between Diffraction Compensation on and off, viewing at 100%. There should be a noticeable effect in the innermost region of the chart. After that move on to real world images with some distinct edges (sign lettering etc) and once again shoot with f/22.

Dave

[Dinarius]

Dave,

Many thanks for the reply.

D.