Rollei Prego Micron compact camera lens conversion project and samples.
The lens is a Schneider-KREUZNACH AF-Curtagon 1:3,5 f=30mm/24mm HFT taken from a Rollei Prego Micron with a broken shutter and converted to L39.
Rollei Prego Micron is a licensed clone of the famous Ricoh R1/R1S. Dual focal lengths are offered. The lens has lots of character when set at 24mm and people often remove or disable the panoramic frame mask to get the vignette look. The frame mask is normally in place when the camera is used at 24mm, but this crops most of the vignette off.
It wasn’t hard to remove the lens from the body, remembering to safely discharge the flash storage capacitor. [DANGEROUS, don’t disassemble the camera, you have been warned, etc.] The tricky bit was disassembling the lens module and (1) disabling the lens cover doors and (2) removing the shutter leaves. The lens can still be swapped between f=30mm and f=24mm (currently with disassembly) and can still be focussed, although I leave it set at 24mm and the hyperfocal distance is from 2 feet to infinity. The lens was mounted through a Leica Screw Mount body cap, because it potentially offers me more mounting options than Leica M-Mount.
All these sample images were taken on a Sony A7R. This sensor vignettes more and has more purple shift than you see with film; that’s a problem typical to these simple rear projecting wide lenses when used on digital full frame cameras. I would prefer to use it with film, but I would have to find a way to further reduce the size of the lens module in order to accommodate the lens within a rangefinder body which has a rangefinder coupling. It also does not work on my Bessa-L and GXR-M because they have protective baffles that get in the way. It’s a project in progress.
That said, the images it produces look lovely.
Trivia: Schneider Kreuznach licensed the name Curtagon to Rollei. Apogon is not just a genus of reef fish but the name Rollei Fototechnic apparently used when it couldn’t license someone else’s name. I’m not sure what the lens formula is but there are physically separate 4 pieces of glass (one is in place when the lens is in 24mm configuration) and none appear to be cemented doublets. The shutter goes between the second and third element. The third element is the optional one.
Original text and images are copyright Dan K (2015). All rights reserved, but limited permission is granted for reblogging on tumblr with attribution and in complete form, including this rider.