That being said Leica SLR lenses are really nice glass and it's a shame they never made them in third party mount for example Nikon F, Pentax K mount, etc.
In this particular set, I went out on a damp Sunday morning with a black Leicaflex SL and got a chance to put a 21 F4 Super Angulon through it's paces along with the 35 f2 R Summicron that I used as the prime lens on the camera. The film used was Fuji Pro 160 S rated at 100 ISO.


