Interesting PETZVAL 8" with f/2.8?

[renes]

I bought this barrel petzval recently, I thought it was Voigtlander RR Euryscope. When I unscrewed rear part it turned out it was build of two separate cells (flint and crown) and both are mounted in threaded housings. It's the first time I see petzval air spaceed rear group in such housings. Was it uncommon? Do you have any idea what brand name this petzval could be? And it is very fast, focal lenght measured at infinity to the slot is 8" and the front lens diameter is 70mm (2,75") what gives f/2.8.

Rear group is on the right side:

http://img820.imageshack.us/img820/5731/pt1ai.jpg

http://img405.imageshack.us/img405/7512/pt2cx.jpg

http://img810.imageshack.us/img810/3144/pt3l.jpg

[eddie]

ross and dallmeyer had their rear petzval groups that screw together.

one had the crown in the rear the other did not. that may give you a clue.

i have a giant voigtlander 7B lens that screws together in the rear as well. serrial #23xxx. i also have a giant 7B like lens that also screws together and it's serial # is 12xxx. all the other petzval lenses made by voigtlander that i have seen have the "regular" spacer ring inside.

eddie

ps. the 7 b is essentially a 14 inch f3 lens. the other one is one inch longer in FL with the same size glass. i bet it was an "early" 7b pretty damn fast as well. too bad you are missing the sleave.

[renes]

Thanks eddie!

I checked it and it has 4B mark. So, Dallmeyer or Voigtlander ?

I do not know what to do with this barrel lens, maybe I will make a brass sleave with mounting ring? :) I need 6-7" Dallmeyer RR f/8 so this could be a nice lens for trade :)

http://img839.imageshack.us/img839/7342/49278500.jpg

[eddie]

voigtlander.....well done! it is f3

too bad you do not have the sleeve for it.