Focus peaking is the name for an electronic display technology, which highlights the areas of sharpest focus in an image with a false-color halo. (The halo color is sometimes switchable according to the user's preference.) This technology originated with professional videography equipment; but circa 2011, began to appear on stills cameras such as the Sony NEX series. It is only possible on digital cameras whose image sensor is able to provide continuous live video, for example in a mirrorless compact system camera or a DSLR with its mirror raised.
Focus peaking represents the first wholly original focusing method to appear in still photography in decades (taking its place alongside scale focusing, ground glass focusing, rangefinders and autofocus). It is a welcome feature when a photographer wishes to use manual-focus legacy lenses on a digital camera, ordinarily designed to use autofocus.
- Sony NEX-C3 focus peaking demonstration, with two video clips; from sonyalphanex.blogspot.com
- Video demonstration of focus peaking using Pentax K-01, from Ned Bunnell on Vimeo
- June, 2011 report on Sony NEX-3 and NEX-5 firmware update adding focus peaking, with video demonstration; from Popular Photography
- December, 2010 review of Marshall V-LCD50 video monitor with illustration of focus peaking feature; from Luminous Landscape