Zeiss's compact Contax telephoto — the Sonnar T* 100mm f/3.5, lightweight manual-focus glass for the C/Y mount.
The Zeiss Sonnar T* 100mm f/3.5 was a compact telephoto prime for the Contax/Yashica mount, offered from the early 1980s as a small, light short tele. The Sonnar design kept its size and weight down.
This is a manual-focus C/Y-mount lens with a 100mm focal length and a maximum aperture of f/3.5. The Sonnar layout produced a notably slim and portable telephoto. Other optical details are omitted where they cannot be verified.
At 100mm the lens suits portraits, travel and general telephoto framing, offering reach and compression in a package that is easy to carry all day. It renders cleanly and pairs well with lighter Contax bodies.
Used copies are relatively affordable and appeal to those wanting a compact Contax telephoto. Look for internal haze, fungus and coating wear, confirm smooth focus and clean aperture blades, and check the front element. It adapts to mirrorless with a C/Y adapter.