Disclaimer: I don't want to bring this thread OT. So, this will be my last post about DoF in this thread. Originally posted by nixcamic As the megapixel war rages on, DoF keeps getting shallower and shallower [...] I probably shouldn't have written it
Didn't I write "
please, all refrain from answering on this remark"?
nixcamic, as you write, this isn't the thread. So, to just mimimize
confusion and because you spent so much time on it...
For DoF calculations, the circle of confusion (CoC) is traditionally defined to be something like image-diagonal/1730 (*). It reflects the resolution limit of the human eye when looking at the entire image. Where walking closer is nothing but cropping (remember my cropping remark that cropping changes DoF?
)
The CoC is
much larger than the pixel pitch (like 5x for a K20D). You
can ask at the subject distances which still render sharp pixels. But this is
not called "
depth of field" DoF. You
must give it another name. Because DoF is an established term defined independently from digital technology.
Therefore, DoF is independent from megapixel. By
definition.
--
(*) For 1730, cf.
Zeiss formula - Wikipedia, the free encyclopedia and it doesn't matter if this or any other
constant is used. Pentax seems to use 1500 on their lens scales. I recommend 2500 in the digital age.