On Wed, 22 Jul 1998 02:49:14 GMT, Tommy.Pickles.nick@night.com (Tommy Pickles) wrote:

>I recently bought a used Vivitar 2X Macro Focusing Teleconverter. I
>have tried it with prime lenses, and zooms, and am able to fiddle with
>the macro ring, and the focusing ring, and for farther away stuff the
>zoom and get nice sharp images, but I haven't been able to come up
>with a step-by-step procedure for its operation.

This converter (as with most short-lens 2X converters) is best used
with fixed-FL lenses from about 28mm to 135mm and with the diaphragm
set for f5.6-f16 (about f11, for sharpest results). It multiplies the
effective FL by 2 (and lens speed is reduced by two stops - more when
the variable extension tube is used...), and it has a built-in second
focus ring that allows closer focus than normal with the lens alone.
It is a neat unit of good optical quality.

>Also, there is a pair of scales around the moving ring (macro ring?)
>spaced about as below. I think it is the macro ratio, but what do the
>2 scales denote?

Looks like the magnification ratio with a 50mm lens focus ring
set at infinity, and at .45 meter...