The standard formula for optimum pinhole diameter is quoted everywhere, but has anyone actually done some experiments to see if photographic results confirm it? I saw a quote by Larry Bullis somewhere to the effect that he had not observed any diminishing returns in going smaller. Here it is:
http://www.???????/resources/articles/makingholes.php Looking at the derivation of the standard formula it seems to make some assumptions that might not reflect the way we actually perceive photographic sharpness. In particular the notion that the outer diffraction rings are strong enough to be perceived as lack of sharpness at all pinhole diameters beyond the 'optimum' bears scrutiny. Just wondering. -- John Brownlow http://www.pinkheadedbug.com