Cameras

A camera is an optical instrument that records images by capturing light on a photosensitive surface. It typically comprises a light-tight body, a lens, a shutter, and a sensor or film. Digital cameras use electronic sensors—usually CMOS or CCD—and store images as files, while film cameras rely on light-sensitive chemical emulsions.

Historically, camera obscura devices preceded photographic processes in the 19th century, followed by interchangeable-film formats and the rise of the single-lens reflex (SLR). Since the 1990s, digital imaging has diversified into several families and sizes.

Modern cameras fall mainly into two groups: fixed-lens compacts and interchangeable-lens systems. Interchangeable-lens cameras include DSLRs and mirrorless models, which allow lenses to be swapped; fixed-lens cameras have a non-removable lens. Lenses determine fields of view; aperture and focal length affect exposure and depth of field. Exposure is controlled by shutter speed, aperture, and ISO. Autofocus and metering systems assist focus and exposure, with modes ranging from automatic to manual.

Storage is on memory cards for digital cameras or film for analog cameras. Digital files may be saved as RAW for maximum flexibility or JPEG for ready use. Applications span consumer photography, journalism, cinema, science, and research, with ongoing advances in computational photography, high-resolution sensors, video capabilities, and color science.