Supplementary lenses

SUPPLEMENTARY LENSES
Supplementary lenses are clamped on the front of the Nikonos lens. Their strength is measured in diopters (for example - 1, 2 or 3 diopters as the lenses increase in strength).

Supplementary lenses - additional lens elements used with the standard camera lens to provide a new focal length.
Surface development - development process in which the image forms primarily on the surface of the emulsion and then penetrates deeper.

The heart of the system was a series of supplementary lenses that could be removed and replaced under water.

It can be extension tubes, bellows, or supplementary lenses.
Coated lens: A lens with coated surface such as magnesium fluoride to reduce flare.

A camera store could never sell you a "magnifying glass" for $50 so they call these things "supplementary lenses" or "close-up lenses". Good things about close-up lenses: ...

See also: Subject, Lens, Light, Camera, Lenses