Whiskers wrote:
On 2013-01-30, Rob wrote:

[Pinhole photography]

Size doesn't matter, its the desired results.

Well a big hole makes for a faster exposure but less sharpness, so size
does matter!

Well, a small hole makes for a slower exposure but less
sharpness as well, so size does matter. (Think Airy disk)


(Calculate the aperture by dividing the diameter of the hole
into the distance from the hole to the film; eg if the hole is 1mm diameter
and 100mm from the film, the aperture is 1/100 - usually expressed as 1:100
or f/100. There will be about 1mm of fuzzines in the image in this
example).

The optimal pinhole is perfectly round and has a size of
d = SQRT(2 f λ)
with f = focal length and λ the wavelength of the light.

-Wolfgang