Olympus's OM telephoto zoom — the Zuiko Auto-Zoom 65-200mm f/4, constant-aperture reach.
The Olympus OM-System Zuiko Auto-Zoom 65-200mm f/4 is a telephoto zoom for the Olympus OM mount, introduced in 1983. The Auto-Zoom token marks the automatic diaphragm. It covered a versatile short-to-medium telephoto range with a constant f/4 aperture, giving OM photographers a flexible portrait and telephoto zoom in a single lens.
This is a manual-focus Olympus OM zoom with a 65-200mm focal range and a constant maximum aperture of f/4, designated Auto-Zoom. The constant f/4 aperture holds across the range, which helps with manual exposure. The verifiable specifications are the 65-200mm focal range, the constant f/4 maximum aperture and the manual-focus OM mount; element count, filter thread and weight are omitted rather than guessed.
A 65-200mm zoom runs from a short telephoto through to substantial reach, covering portraits, candid work and distant subjects in one lens. The constant f/4 aperture gives reasonable speed for a telephoto zoom and keeps exposure consistent through the range. It suits portraits, travel, sport and wildlife where the flexibility of a zoom outweighs the ultimate speed of a prime.
This telephoto zoom is moderately common on the used market and reasonably priced. 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, even travel with no play, and check the aperture ring for firm clicks. It adapts to mirrorless as a flexible constant-aperture telephoto zoom for portraits and general reach.