Today I found (Or bought, rather) an interesting Derogy lens, it's a somewhat newer Derogy lens considering it has a built in aperture with a lever sticking out for adjusting it with a normal f/stop scale (f4 to f22).
On one side is the logo and serial; No 32863, Derogy Fab.T, Brevete Paris & Londres. On the other side is the lens' name and number; a Portrait No. 2. Focal length appears to be around 210mm.
I didn't find it in the vade mecum and I can't unscrew the front lens to find out the optical formula. The rear elements (2) make it look like a petzval. Anyone have any info or user experience with this lens?
I also found a cute little old E. Krauss lens who used to make Zeiss copies for France, but with a very early serial number. It's a 120mm f7.7 'Anastigmat-Zeiss' with a #967 serial. Am I right into thinking this is an early Protar?
With kind regards,