Lens Lab
    Tamron 400 mm f/ 7.5 T mount model 490
    Tamron 400 mm f/ 7.5 T mount model 490

    Tamron 400 mm f/ 7.5 T mount model 490

    400mm · f/8

    Overview

    The Tamron 400mm f/7.5 T-mount model 490 is an early, simple four-element telephoto lens known for its compact size and light weight (about 1 foot long, 1 pound). Optically, it delivers fine performance wide open with perfect sharpness at f/7.5, but it is dim and difficult to focus in poor light. Build quality is excellent with sturdy aluminum, though the entire front barrel revolves, making handling awkward, and it lacks a tripod adapter. Minimum focus is a long 30 feet. It suits users needing a lightweight, capable long telephoto under bright conditions, but alternatives like the Tamron 400/6.9 are preferred.