50mm Summar (LTF) lenses don't usually thrill me, but the one I saw yesterday was interesting. A slot is cut into the aperture ring on both sides, through which project fixed metal tabs, which limit the aperture-rings travel. The tabs project much further than they would if this lens were otherwise just missing a piece - it looks like an intentional arrangement. It also seems a bit primitive, which I find intriguing. Is this a prototype? Or just one of possibly several variants of this lens? I've browsed through a couple of compendiums, and cannot find this described.

-- John Layton (john.layton@valley.net), April 02, 2002

Answers

It was part of a system which AGFA introduced to allow color photography through a special filter system (the introduction of Kodachrome killed it). There was a similar set up on a few Thambar lenses.

-- Bill Mitchell (bmitch@comcast.net), April 02, 2002.

It could be a lens designed to take a special Agfa filter (which itself is much rarer than the lens). Only very early 50/2 Summar lenses were built this way. If you tell us what the serial number is, I can assess whether this may be one of those early lenses.

-- Eliot (erosen@lij.edu), April 02, 2002.

I have a 7.3cm Hektor that has similar cut outs.

Adam

-- adam g. lang (aglang@hotmail.com), April 02, 2002.

My apology to the group for disseminating false information. It was indeed the 7.3 cm Hektor, not the Thambar which was used for the AGFA color filter system (in addition to the Summar).

-- Bill Mitchell (bmitch@comcast.net), April 02, 2002.

Hmm... and people accuse me of disemminating false information a few months ago :( ... grrrrr...

-- Alfie Wang (leica_phile@hotmail.com), April 02, 2002.