Olympus's compact OM telephoto zoom — the S-Zuiko Auto-Zoom 100-200mm f/5, light medium reach.
The Olympus OM-System S-Zuiko Auto-Zoom 100-200mm f/5 is a telephoto zoom for the Olympus OM mount, introduced in 1983. The S-Zuiko prefix denotes an Olympus element code and the Auto-Zoom token marks the automatic diaphragm. It covered a compact medium-telephoto range in a single lens, giving OM photographers a light and simple long option.
This is a manual-focus Olympus OM zoom with a 100-200mm focal range and a constant maximum aperture of f/5, designated S-Zuiko Auto-Zoom. The constant f/5 aperture holds across the range, which aids manual exposure, and the modest range kept the lens compact. The verifiable specifications are the 100-200mm focal range, the constant f/5 maximum aperture and the manual-focus OM mount; element count, filter thread and weight are omitted rather than guessed.
A 100-200mm zoom covers the medium-telephoto range, well suited to portraits, candid work, sport and distant subjects in a compact package. The constant f/5 aperture gives consistent exposure across the range and keeps the lens light and easy to carry. It is a practical, no-fuss telephoto zoom for travel and general reach where extreme speed is not required.
This telephoto zoom is moderately common and affordable on the used market. Inspect the glass for haze, fungus and internal dust, and confirm the aperture blades are dry and clean. Test the zoom and focus movements for smooth travel with no play, and check the aperture ring for firm clicks. It adapts to mirrorless as a compact medium-telephoto zoom, with its slower aperture the main consideration in dim light.