Olympus's OM telephoto zoom — the Zuiko MC Auto-Zoom 85-250mm f/5, multi-coated reach.
The Olympus OM-System Zuiko MC Auto-Zoom 85-250mm f/5 is a telephoto zoom for the Olympus OM mount, introduced in 1979. The MC designation marks multi-coated optics and the Auto-Zoom token marks the automatic diaphragm. It covered a short-telephoto to long-telephoto range in one lens, giving OM photographers flexible reach for distant subjects.
This is a manual-focus Olympus OM zoom with an 85-250mm focal range and a constant maximum aperture of f/5, designated MC Auto-Zoom. The MC coating aimed to reduce flare and improve contrast, and the constant f/5 aperture holds across the range. The confirmed specifications are the 85-250mm focal range, the constant f/5 maximum aperture, the multi-coating and the manual-focus OM mount; element count, filter thread and weight are omitted rather than guessed.
An 85-250mm zoom spans from a short portrait telephoto to a long reach, covering portraits at the wide end and distant subjects at the long end without swapping lenses. It suits wildlife, sport, travel and general telephoto work. The constant f/5 aperture asks for reasonable light, and the multi-coating helps maintain contrast when shooting toward bright skies.
This telephoto zoom is moderately available on the used market and generally affordable. Check the glass for haze, fungus and internal dust, and confirm the aperture blades are dry and clean. Test the zoom and focus actions for smooth travel with no play, and verify the aperture ring clicks positively. It adapts to mirrorless as a flexible telephoto zoom, with its slower aperture the main consideration in low light.