Hello everyone,
I 'm quite new on this forum, but some of you know me as 'mics' from the collodion.com forum.
I need some advice about this lens.



I bought it cheap and was able to take it apart finally but there was no signature on the glass elements.
Except for the cylindrical rear barrel I would say, it is a Jamin Cone Centralisateur lens.

But is it???

All major components are lettered just as the cone lenses are and the reversed front element fits into the flange as well.
Maybe one of you has some new idea about this lens.
You can find more pictures here on my website:
http://www.mics-foto.de/pages/J_D_web/J_D_web.html
Thanks
Michael




From left to right:
Top row: Front cell 'D', front element (cemented pair),retaining ring for front element, two parts of the inner barrel left piece is 'C'.

Middle row: middle barrel (moves back and forth by rack and pinion), main barrel 'B' with an additional 'J' (for jamin maybe???), flange 'A' (mounted on a 5in lensboard), lens hood 'F'.

Bottom row: Rear element barrel (equivalent to the cone on centraliateur lenses) 'F', Rear element (airspaced pair), distance ring, retaining ring for rear element, Rear Cell 'G'.

Hi Michael,

If it doesn't have the engraving or the penciled tag on the edge of the elements, as J/D lenses always did, I doubt that it is a Jamin and (or) Darlot. There were, of course, many generic lenses made back in the day that had fine brasswork and optics, which are perfectly usable, so it doesn't matter much except to collectors if there is no name on the lens. It looks like a nice piece and the engraved letters and such are kinda cool.

Jamin did make a convertible lens that lacked the cone, just a regular Petzval portrait lens that was made to easily reverse so it could be used as a landscape lens (a design later used by several French manufacturers - I've seen Hermagis, E. Francais, and a few others like that). It would be my guess that yours is a similar design of generic manufacture, quite possibly from France.

I hope that helps,

Paul