500mm · f/6.3
The 3M-6A 500mm f/6.3 mirror lens delivers surprisingly good handheld results, though a tripod is recommended for consistent sharpness. Optical quality is praised as comparable to much more expensive lenses (Attila). However, shallow depth of field and focusing difficulty without a tripod are noted (woodrim). Build and handling are typical for a mirror lens; it suits photographers seeking a compact, affordable super-telephoto for stationary subjects.