ABSTRACT
Enlarging and copying lenses all show some degree of symmetry and are used to project film onto sensitized paper (or other photosensitive medium). The enlarging lenses generally cover magnification ratios 2–8 or 8–16. The later case is for enlarging 35-mm single-lens reflex (SLR) film to 8 × 10 or 11 × 14 in. prints. F-numbers are usually f/2.8 or larger.
