Cosina's budget telephoto zoom — the basic 100-300mm for Minolta MD mount.
The Cosina 100-300mm f/5.6-6.7 is a budget telephoto zoom for Minolta MD mount. Cosina manufactured affordable lenses and camera bodies — also producing for Voigtlander and other brands. The very slow f/5.6-6.7 aperture severely limits practical use. A very basic telephoto option at minimum cost and capability.
Basic optical quality. The extremely slow variable aperture limits use to bright daylight. Sharpness is acceptable in the centre when stopped down. The 100-300mm range provides telephoto reach. Build quality is basic Cosina consumer grade. Adequate only for casual daylight telephoto. Not recommended for any demanding photography.
Minolta MD mount — discontinued. Filter thread varies. Weight varies. Build quality is basic. Manual focus. The Minolta MD mount adapts to mirrorless. The very slow aperture makes this one of the most limited telephoto options available in any mount. Better MD telephoto alternatives exist at similar prices.
Essentially valueless. Very slow aperture. Basic quality. Not recommended. Better MD telephoto options exist. Only if completely free with a camera purchase. The extremely slow f/6.7 at 300mm is barely usable even in bright daylight.