SLR Camera Lenses

Match the lens mount to your camera's mount and confirm full-frame vs. APS-C/ DX compatibility; then choose focal length and aperture based on use (wide-angle for landscapes, standard/portrait focal lengths for general use, telephoto for sports/wildlife)

A medium telephoto focal length (85–135mm on full-frame, or equivalent crop-adjusted range) with a wide maximum aperture (f/1.8–f/2.8) gives flattering perspective and shallow depth of field for portraits

Third-party lenses can offer good optical value and unique features, but check compatibility, autofocus performance, build quality, and warranty; read reviews and sample images because performance varies by model and camera combination

Verify whether the lens has built-in autofocus and whether it supports your camera's autofocus systems; choose a lens with optical image stabilization (or rely on in-body stabilization) if you need sharper low-light or handheld telephoto shots

Cameras with APS-C or other crop sensors multiply a lens's focal length by the crop factor (commonly ~1.5x for APS-C), narrowing the field of view compared with the same lens on a full-frame body

Look for metal mounts, robust housing, and explicit weather-sealing specs if you shoot outdoors; note that not all lenses are sealed and weather resistance also depends on the camera body

Use a soft blower and microfiber cloth for cleaning, keep front/rear caps on when not in use, store lenses in a dry, padded case, and service or replace faulty elements or seals if you notice fungus or mechanical issues