Marc Wossner wrote:
Hi NG,

Can someone please explain to me if there is a connection between the
Nyquist sampling theorem and the resolution limit of a digital image
sensor? I mean, does it imply something like a lowest mark as far as
pixel spacing is concerned? - I´m quite new to digital photography and
keep reading about this stuff but must admit that it´s by far too
theoretical for me!

Marc Wossner

There was much work done on this in the thirties by early TV engineers,
since in the vertical direction image tube TV and kinescopes are
"sampled" systems. Much of the work was done' experimentally, and the
guru was an engineer by the name of Ray Kell. The resulting widely
used value, now called the Kell factor, was around 0.7. That is, for a
system with N samples in a given direction (either vertical or
horizontal) one can resolve about 0.7N lines.

When we got our hands on our first CCD chip at work in the late '70s, I
did an analysis (numerical, sort of Monte Carlo) and found a value
very close to that for mosaic arrays. While it did depend a bit on
fill factor, the dependence wasn't strong. I still use 70% as a good
expectation.