Overview

The Aetna-Coligon 135mm f/3.5 is a telephoto prime for 35mm SLRs, built by Sankor and sold under various brands. Optical strengths include decent resolution and good sharpness, but weaknesses are strong magenta chromatic aberration in backlight and inferior flare resistance compared to Tele-Xenar. Build is typical Japanese DKL mount with a close 7-foot minimum focus distance. It suits users seeking an affordable vintage telephoto with acceptable performance, but not for demanding backlit scenes.