I am 60 years old. I'm not a student and this is not homework (despite somebody trying to close it as a "homework question".)
I'm interested in building a long-focal-length pinhole camera (by "long" I mean 1 to 10 meters). I'm aware that will involve very long exposures and am planning to used a Peltier-cooled CCD for an imager (except maybe for solar viewing).
But I'd like to know if it's worth bothering - how much resolution can I expect, given a pinhole size and focal length (hole-to-sensor distance)? Will diffraction make this entirely pointless?
How would I go about calculating the expected resolution - clearly (to me) there's a contribution from the hole size (resolution will drop with a bigger hole), but diffraction will increase as the hole gets smaller.
Surely there must be some well-known formula for calculating this - what is it?