Mitsuki — third-party manual-focus 80-200mm f/4 telephoto zoom, multiple SLR mounts
Mitsuki was a minor third-party lens brand of the 1980s, part of the large field of budget Japanese zooms marketed under smaller trading names to fit popular manual-focus SLR systems. The 80-200mm f/4 sat among the more ambitious offerings, matching the constant aperture of costlier first-party zooms.
The lens covers the 80-200mm range with a constant f/4 maximum aperture through the zoom, a spec more common on premium first-party lenses than budget third-party ones of the period. It was made to fit several major manual-focus SLR mounts of the 1980s, letting one design serve multiple systems.
A constant f/4 aperture at this range was a real selling point against variable-aperture rivals, though build and coating quality trail the first-party lenses it undercut, with more flare and softer edges wide open. It suited photographers wanting reach without paying for branded glass.
Mitsuki lenses are uncommon in today's UK secondhand market and generally inexpensive when found, appealing mainly to collectors of vintage third-party optics. Test the zoom and focus rings for smooth travel, check the aperture blades operate without sticking, and confirm the mount before purchase.