33. FOCUS PEAKING

THE INTEGRATION OF video and still technology has generated a feature we can be thankful for: focus peaking. Originally designed for video cameras, this feature allows you to easily see where the lens is focused when viewing the full image. As the focus ring is turned back and forth, the region of sharpness will have a wave of glimmering edges that are easy to identify. Designed using edge-detection technology, focus peaking first became commonplace with mirrorless cameras. Many DSLRs have since incorporated this option into their Live View modes.

This feature is usually not enabled as a default so you will have to look in your camera’s menu for focus peaking; it’s usually located within the focus assist options. Many cameras offer additional preference settings beyond just turning peaking on and off. Different colors for the halo may be available, such as white, red, blue, or yellow. This can be helpful depending on your subject matter and its color.

The level of peaking may also be adjustable with a low, medium, and high setting. You should set this according to your taste and what works best for your subject matter. If peaking is set too high, it may spread out too much to areas that have strong contrast but not necessarily where focus is critically set. The strong halo may also be a distraction when composing the photo. Choose a color and level combination that is easy to see but doesn’t get in the way.

When viewing your entire scene in an electronic viewfinder, peaking is one of the easiest and quickest ways to see where the camera is focused. With the viewfinder on a DSLR, critical focus is easier to determine because the optical viewing system allows the image to be seen more clearly than on a digital display. Electronic viewfinders are limited by their resolution, usually between 2 million and 4 million dots. Peaking is the best system we have at this time to see the whole image and determine exactly where focus is.

While this feature does an excellent job, it does have a weakness. The way peaking works is by recognizing edge detail. Contrasty edge details are usually only detectable when the camera is properly focused on a subject. Some subjects, however, have lots of edge detail or areas of strong contrast that will cause the focus halo to appear anytime the lens is focused somewhat nearby. For this reason, peaking is inadequate when you need to be hypercritical about accuracy. Peaking works well when you are looking to determine the approximate zone of focus rather than a particular point.