Tamron 24mm f/2.5 — Adaptall-2 wide-angle prime (01B) with close-focus macro, multi-mount fit
Tamron launched the 24mm f/2.5 as model 01B with the Adaptall-2 system in 1979, and kept it in production until 1987. It served as the widest prime in Tamron's manual-focus Adaptall-2 lineup for most of that run.
Built to Tamron's 'CF' close-focusing wide-angle design, the 01B combines standard wide-angle framing with closer minimum focus than most contemporaries. It uses the Adaptall-2 interchangeable mount, available in Canon FD, Nikon F, Minolta MD, Olympus OM, Pentax K, Konica AR, Contax/Yashica and M42 fittings.
At 24mm, it gives noticeably wider coverage than Tamron's 28mm primes of the same generation, useful for interiors, landscapes and environmental work, while the close-focus capability lets it double as a wide-angle detail lens rather than a strictly landscape-only optic.
As one of the wider Adaptall-2 primes, it is sought after by users of vintage-lens adapters on modern mirrorless bodies. Check front-element coating for wear and haze common at this age, confirm the aperture ring clicks cleanly through its range, and verify the adapter supplied matches the camera.