DSLRs

DSLRs are digital single-lens reflex cameras that use a movable mirror and an optical viewfinder to compose images. Light entering the lens is reflected by the mirror up into a pentaprism or pentamirror and then to the eye through the viewfinder. When a shot is captured, the mirror flips up, the shutter opens, and light reaches the image sensor.

DSLRs feature interchangeable lenses and digital sensors, typically in APS-C or full-frame formats. They usually include an optical viewfinder, which provides real-time, through-the-lens composition, and they support a wide range of accessories such as external flashes, battery grips, and specialized lenses.

Autofocus in DSLRs traditionally relies on phase-detection AF via a dedicated module or the main sensor when using the viewfinder. In live view, some models switch to contrast-detection AF or on-sensor phase-detection. DSLRs generally offer robust battery life and a large lens ecosystem, with storage via CF or SD cards and RAW capture options.

Compared with mirrorless cameras, DSLRs retain an optical viewfinder and, in many cases, longer battery life and fast still-photo autofocus in viewfinder mode. They tend to be bulkier and heavier, and live-view autofocus can be slower on some bodies. The design also imposes a longer lens-to-body distance, influencing overall size and compatibility.

Market status and uses: DSLRs continue to be produced by some brands but have declined as mirrorless systems have gained market share. They remain popular among professionals and enthusiasts in genres such as sports, wildlife, events, and travel for their durability, long battery life, and compatibility with a long-standing lens lineup.

Examples include Canon EOS 5D Mark IV, 6D Mark II; Nikon D850, D750; and Pentax K-1.