EVF

An electronic viewfinder is a small high-resolution display mounted inside the camera's eyepiece housing. Looking through an EVF shows a live image rendered from the sensor, updated in real time as the camera or settings change. Unlike an optical viewfinder on a DSLR, which shows the scene directly through the lens via a mirror and prism, an EVF shows a digital representation of what the sensor is currently capturing at the active exposure settings. What you see is exactly what the sensor sees.

The most practical advantage of an EVF over a rear LCD screen is visibility in bright sunlight. Direct sunlight washes out rear screens, making exposure and composition assessment difficult outdoors. An EVF is viewed through an eyecup that blocks ambient light, maintaining full visibility regardless of ambient brightness. Shooting with the camera raised to the eye also stabilises the camera against the face, reducing camera shake compared to shooting at arm's length with the rear screen.

EVFs show the scene as the sensor currently sees it, including the effect of current exposure settings, white balance, picture profiles, and filters applied. A camera with an optical viewfinder shows the scene at natural brightness regardless of exposure settings, requiring a test shot to verify exposure. With an EVF, overexposure, blown highlights, and underexposure are all visible in real time before the shutter is pressed, allowing immediate correction without shooting a test frame.

EVF specifications relevant to image quality include resolution in dots or megapixels, magnification (how large the scene appears relative to the unaided eye), and refresh rate in frames per second. Flagship M43 bodies offer high-resolution EVFs with fast refresh rates suited to manual focusing and tracking moving subjects. Entry-level M43 EVF bodies have lower resolution and magnification. Not all M43 cameras include a built-in EVF; compact bodies often rely entirely on the rear screen, sometimes with an optional clip-on EVF accessory available.