OptiCalc is a utility for photographs made for calculating depth of field, light condition, 35mm equivalent focal, minimum shutter speed, field of view, etc. from three input parameters: focal length, aperture and subject distance. It works for different types of cameras and it is possible to add others by editing a plist file.
Version 0.3.2: Russian localization (Thanks to Michael Krekin).
Mac OS X 10.4.11 or later