The Mamiya Sekor Z 180mm f/4.5 is a short telephoto prime designed for the Mamiya RZ67 medium-format SLR system, with the leaf shutter built into the lens barrel as is standard for the RZ67 line. It was aimed at portrait and short-tele work on 6x7, where its modest aperture and focal length give a flattering working distance and pleasing subject separation.

At UK auction in recent years, hammer prices for this lens have ranged from around £25 to £100, with the two recorded saleroom results sitting either side of a roughly £60 midpoint — wholesale levels achieved before buyer's and seller's commission. As of 2026 the 180mm f/4.5 remains one of the more affordable RZ67 Sekor Z optics at auction, so what a clean copy is worth today depends heavily on cosmetic condition, glass clarity, and whether the leaf shutter is firing accurately. Price spread is wide for so few data points, and a tested, fungus-free example will typically sell for more than a cosmetically rough or untested one.