An electronic viewfinder is essentially a tiny high-resolution video screen that shows a live feed from the camera’s imaging sensor. In that sense, it works like Live View on the rear LCD, just in a much smaller display inside the viewfinder.

Because the image comes from the sensor, cameras with EVFs usually do not need the traditional mirror-and-prism optical path of a DSLR. In some designs, if a mirror is present, it may be partially reflective for autofocus purposes rather than sending the image to an optical finder.

Compared with an optical viewfinder, an EVF can offer some advantages:

• show exposure and color preview closer to the final image
• display overlays such as histograms, focus aids, and shooting info
• avoid mirror movement and its vibration

The tradeoff is that it is an electronic display rather than a direct optical view, so it depends on sensor readout and screen performance.