Jack Hogan

Got it, thanks Erik. BTW I did not even know that imsharpen existed:-) but I see that it provides simple USM sharpening. How do the results above compare to deconvlucy with a gaussian, Airy or - ...

Erik, does the legend imply that you used a radius of 1.3px for both, and amounts of 50% and 150% for f/5.6 and 11 rep?

When the E-M5II came out with pixel shift I did some thinking and MTF testing of its output using the slanted edge method and MTF Mapper. Here is some of the thinking. There appear to be two ...

Just a guess, Frans and Iliah, based on their wording and the precept 'first, do no harm'. I look forward to updating my guess as we learn more.

A few test images popped up online, including on Jim's blog. My guess (based on very little actual information:-) is that they concentrate on reducing false color and aliasing artifacts as a ...

How about the area under the MTF curve above Nyquist, as a metric for aliasing? Unweighted or weighted. Jack

Very, very good question Erik.  Intuitively I would guess that two additionally useful parameters in your investigation could be aliasing and noise, because sharpening normally increases both.  ...

Moi? For having the audacity to suggest that one of your statements may have been incorrect? An intellectually honest person would have said 'yeah, I hadn't realized that those P45+ MTF curves ...

Yeah, but 1 what? The null is at sinc(1/w) with w the physical width of the effective pixel aperture. With 100% fill factor w is the same as pixel pitch, so the null occurs indeed at sinc(1) in ...

I don't know. What I do know/suspect is that pixel configuration seemed to be fixed throughout the normal ISO range until Sony bought Aptina's patents. From that point on we first started seeing ...

Good stuff Erik, keep at it!

So either your statement above or this chart is incorrect. P45+ 1 c/p = 5412 lp/ph.  a7rII 1 c/p = 5304 lp/ph. jack

They look good Erik. The question is, what’s the objective of sharpening? Restore sharpness lost during the capture process, artistic licence, or preparation for output? If the former, there is too ...

Sometimes one has to wonder.  What’s your estimate for MTF at 1 cy/px?

Yes, that would imply that they wrote the BlackLevel subtracted value to the raw file, as was customary for some brands in those days (with Nikon, up to the D810).  The BlackLevel before ...

I always assumed that there was some linearization happening in-camera before the data was written to the raw file (even at base ISO) but Iliah suggested that's not the case , resulting in white ...

This could make the G9 at ISO 100 an interesting case study of the 'hidden' non-linear portion of current pixels. Upon further thought, I believe that Panasonic set up the G9 'properly' at its base ...

Upon further thought, one immediately useful application of these formulas is determining the accuracy of RawDigger Selection Sample statistics: I often find myself dealing with small areas of ...

What would be in the numerator and in the denominator, in physical units? Right, but aren't in-camera ISO labels are somewhat arbitrary?

Wouldn't that be 16.8273%, from Bill's article?  (646 / (4094 - 255) = 16.8273%)