Floyd Davidson wrote:

The "correct" use has evolved. Get used to it because it
won't regress.

The word "evolved" suggests that one use of the term grew out of
the other. This does not appear to be the case. Both uses of
"prime lens" appear to be current and I believe that they are
almost totally unrelated to each other.

For instance in:

http://www.zeiss.de/de/photo/home_e.nsf/1e142195de4e09fac12566fe003b2618/49143eeb494bfa7bc12569770054c1a7/$FILE/ATTBESGB/CLN8.pdf

I read:

"With the Zeiss Mutagon 0.6x there is now a wide-angle converter
available which matches the optical performance level of the Zeiss
Vario-Sonnar 1,7-2,2/3,3-33 lenses used in high quality digital
camcorders from Sony. . . . The Mutagon is threaded to the front
of the prime lens, as distinguished from the well-known Zeiss Mutar
which is inserted between the lens and the camera."

This clearly shows that the term "prime lens" has been in recent
use to describe a zoom lens when used with a supplementary lens.

Peter.
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