DSLR

A digital single-lens reflex camera (DSLR) is a digital camera that uses a single-lens reflex optical system to route light from the lens to an optical viewfinder. Through-the-lens viewing lets photographers compose before capture. DSLRs became widely used by enthusiasts and professionals from the 1990s onward.

In a DSLR, light travels through the lens and is reflected by a mirror into a pentaprism or pentamirror to form the viewfinder image. When the shutter release is pressed, the mirror flips up, the shutter opens, and light reaches the sensor to record the photograph. Live view can use the rear display or an electronic viewfinder on some models.

DSLRs use interchangeable lenses and sensors typically in APS-C or full-frame formats. Autofocus relies on phase-detection in viewfinder mode; some models use contrast-detection or on-sensor phase detection in live view. Images are stored as RAW or JPEG, and many models support video recording.

Advantages of DSLRs include an optical viewfinder with no display lag, long battery life, and a broad ecosystem of lenses and accessories. They tend to be bulkier and heavier than mirrorless cameras, and newer sensor and video features have increasingly shifted toward mirrorless systems.

DSLRs originated in the 1990s and dominated professional and enthusiast markets for years. Since the mid-2010s, mirrorless cameras have eroded this dominance, though DSLRs remain in use and production in some lines.

Leading brands include Canon and Nikon; others such as Pentax have produced DSLRs, while Sony offered DSLR models before pivoting to mirrorless. Availability and support vary by manufacturer and region.