Build quality: good
Filter thread: 49mm
Infrared Mark: yes
Another Porst lens with unknown OEM origin. Bought on ebay together with a camera. Nice. The smallest bright standard lens I have. It takes a 49mm filter and matches the *ist DS: Small but capable.
Porst Color Reflex reversely mounted, stopped down to f/16, internal flash diffused with white paper.
Shot handheld with a Heliopan 715nm IR pass filter. Shot in RAW, converted with pixmantec's RawShooter Essentials .
shot with reversed lens, 28mm extension ring and internal flash diffused with paper.
Cropped and resized 50%, turned 90° clockwise.
More shots with this lens in my Gallery: Porst_50mm_1.7.html