Archived posting to the Leica Users Group, 1997/06/29

[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]

Subject: More info on electrical lens contacts on the R8
From: Carsten Bockermann <Carsten_Bockermann@compuserve.com>
Date: Sun, 29 Jun 1997 04:48:25 -0400

When I visited the Solms factory about two months ago, I saw the
calibration process for the lenses that have the electrical contacts for
the R8. Actually the way it works is fairly easy : the lenses are put on
device that measures actual light transmission. The computer then prompts=

the operator to close down the lens diaphragm to the marked stops, one by=

one. For each stting, the actual (effective) f-stop is measured and
programmed into the lens=B4 PROM. So, a camera having access to this
in-memory table will know that a setting of f/5.6 on the lens actually
means f/5.72 and can correct the exposure accordingly.

Carsten