Optics for Digital Photography
Author : Dr. Karl Lenhardt, Bad Kreuznach
The role of optics in conventional photography (with film materials) is very wellknown to professional photographers. They know how to correctly estimate the relative values of exposure, aperture, picture angle, perspective and its control, f stop, picture sharpness, depth of field, etc.
The new CCD image storage medium (semiconductor image storage) has attributes that make many professional photographers feel insecure about their use:
Which of the "old" rules still apply, what has to be re-thought? Is the quality of my equipment good enough to work with a digital body? Are my lenses suitable for use in digital photography?
To answer these questions, it is helpful to be able to evaluate picture quality, and especially image sharpness, by some repeatable measurement technique that can be documented.