Pinhole QualitySome time ago I discussed the optimum size for a pinhole to be used in digital pinhole-camera photography. I’ve now done some practical work, the results of which are presented here…Pinhole image taken using a Nikon D700 then converted to sepia-tone Image taken using a Nikon D700 then converted to sepia-tone. The pinhole used has an effective aperture of f/180 and an effective focal length of about 55mm.I had a commercially-supplied pinhole sitting in a drawer – I think it came from The Pinhole Resource http://www.thepinholeresource.com – and decided to try this on a Nikon D700. Running some framing tests alongside a conventional lens revealed that the pinhole had roughly the same angle of view as a 55mm lens on the full-frame body. Similarly, exposure tests found that at ISO400 the lens gave a correct exposure at f/8 and 1/250s whereas the pinhole required 2s for the best exposure, giving an effective aperture some nine stops smaller than f/8. This works out to be about f/180, which is exactly the number that was printed on the box containing the pinhole assembly.