Today’s Question: What is “focus peaking”, and why would I want this feature on a digital camera?
Tim’s Quick Answer: Focus peaking is a display on a camera’s LCD or electronic viewfinder that highlights areas of the scene that are in focus. This can be tremendously helpful for establishing or fine-tuning focus.
More Detail: Focus peaking has been common in video capture for quite some time, and I do consider this feature most helpful for video rather than still photography (though it can still be very helpful for still photography). As noted above, a focus peaking feature will highlight areas of the scene that are in focus, and in many cases you can choose the color to be used for the focus peaking presentation on the camera’s LCD display (when using the live view feature) or in the camera’s electronic viewfinder (for cameras that are so equipped).
The reason I consider focus peaking to be especially helpful for video capture is that it enables you to ensure a key subject remains in focus even as that subject gets closer or further away from the lens. It can be much faster and easier to adjust focus based on a focus peaking display rather than on a visual evaluation of the scene through the viewfinder, for example.
That said, focus peaking can most certainly be helpful for still photography. I find focus peaking especially helpful in tricky scenarios, such as in low lighting conditions, when it is difficult to critically evaluate which areas of the scene are in focus. In addition, many photographers with less than perfect vision find focus peaking to be an excellent primary tool for adjusting focus for a scene.
While focus peaking may not be a critical feature for all photographers, I do consider it a feature that can be tremendously helpful. I think it would be beneficial for any photographer who has never seen or used focus peaking to try it out and get a sense of whether they might find this feature helpful enough to add it to the list of “must have” features for their next camera purchase.