Term - Principal point
|Principal point||SWPP and BPPA Photographic Glossary|
Sunday 25th January 2015
A point from which the focal length is measured. The principal point of a simple lens is located at the center of the lens. Compound lenses have two principal points, the location of which cannot be determined by appearance.
Information provided by: SWPP BPPA
SWPP & BPPA, 6 Bath St, Rhyl, LL18 3EB