The Zeiss Nettar 515/16 is 6x6 format. It has a direct optical viewfinder, scale focusing, apertures from f/4.5 to f/22, shutter speeds from B, 1 sec to 1/300.
They are very compact and rigid when opened. The bellows material is of good quality. This camera is fun to use.
Mine originally had a reversed rear element from someone's prior attempt at fixing something. That produced blurry fringe areas. After fixing that, the images are now normal, but I don't think this lens produces very sharp images - maybe it's just my camera. I don't know about the reputation of the Novar lens. At infinity the images are soft. Medium distance seems acceptable. Close up requires careful distance measurement at wider apertures. I've tried to choose f/11 or f/16 for best sharpness - not the usual f/5.6, f/8.
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