A lot has changed in the last 20 years for us photographers—think about how much has changed just in the last five! First, we transitioned away from film (some of us faster than others), and now we are transitioning away from DSLRs toward mirrorless cameras (again, some of us faster than others). While it’s been quite a ride for those of us who remember shooting film, everyone can agree it has made photography easier, and the photos we make are stronger as a result.
Part of this transition, and one of the features that initially drew me toward mirrorless cameras, is focus peaking. It started as a feature of early mirrorless cameras, but it was quickly added to the “live view” options on many DSLRs as well. While often overlooked and misunderstood, focus peaking is one of the most powerful new technological advances in photography over the past several years. Though it may seem useless or even gimmicky for wildlife or action photography, it really comes into its own in landscape photography, where composition is done slowly and methodically—and usually on a tripod.
In its simplest form, focus peaking is a display overlay in your digital viewfinder or LCD that highlights the edges around everything in your frame that is in focus, making it far easier to focus manually (especially with aging eyes). But it doesn’t just highlight what is in focus in the viewfinder. It also highlights what will be in focus based on the depth of field of your selected aperture when the photo is actually captured. As a result, it allows photographers to more accurately choose the absolute best aperture based on their depth of field needs while retaining sharpness.
Precise Focus Versus Lens Sharpness
Many photographers don’t realize there is a difference between being “in focus” and sharpness. While they are related, they are not the same thing. Lenses are typically at their sharpest in the middle of their aperture range. Stopping down a stop or two from wide open will usually give you sharper results. For many lenses, this means their sharpest aperture is ƒ/5.6 or ƒ/8, and by the time you get toward apertures of ƒ/16 and even more at ƒ/22, lenses start suffering from diffraction and again are not performing at their best. When possible, it’s always better to shoot in the midrange apertures if they offer enough depth of field for your composition.
The tradeoff is that as landscape photographers, we often want everything to be “in focus,” which leads us toward smaller apertures like ƒ/16 or ƒ/22—thus giving up lens sharpness in exchange for more depth of field. This has been the bane of photographers throughout time, and it has always been very difficult to determine the best balance of depth of field versus lens sharpness.
In the film days, we used depth of field preview buttons on cameras that had them, looking through a darkened viewfinder trying to determine what was or wasn’t in focus. Those few, highly technical photographers carrying a measuring tape could also calculate an exact depth of field based on the focal point and depth of field scale printed on the lens, but come on—how many of us really did that? Thus, we were left mostly guessing based on rough estimates and experience, and often at the expense of overall lens sharpness.
With the advent of digital cameras, we were finally able to shoot a frame and then immediately review the image on the LCD, zooming in to check critical focus throughout the frame. But this is slow and is still sometimes difficult to accomplish in bright light.
The introduction of mirrorless cameras brought electronic viewfinders and focus peaking, allowing photographers to see in real time through the viewfinder an accurate representation of what will be in focus at any given aperture. No longer are we squinting while we try to look on the LCD in the bright light to check focus. This ability also gives us far more information and control when balancing lens sharpness and depth of field. Perhaps, depending on the composition, you don’t actually need to be shooting at ƒ/16 or ƒ/22 to get everything in focus. Maybe everything will come into focus at ƒ/8 or ƒ/11, where the lens is sharper and that additional depth of field offered by shooting at ƒ/22 is just giving away lens sharpness for nothing.
With focus peaking, I have found myself shooting far fewer images at those small apertures than in the past because now I know without a doubt exactly how much depth of field I actually need. Focus peaking has been a great teaching tool for my students as well as for myself. Sure, there are times when I still shoot at ƒ/16 when I am up close to a field of flowers and want to get the background in focus—but really, is that background ever truly sharp anyway? Can you say tilt/shift lens or focus stacking? That’s another article unto itself.
Focus Peaking & Point Of Focus
Beyond choosing the best aperture for the job, focus peaking also helps us choose the point of focus in an image. Not to get too far into the weeds, but for any given aperture, you get about one-third of the total depth of field in front of the point you focus on and about two-thirds of the depth of field behind the focal point. So, let’s say that the focal length and aperture you are using achieve 15 total feet of depth of field. Five feet of that depth of field will be in front of your focus point, and 10 feet will be behind that point. This is a bit of a simplification as depth of field changes depending on how close you are to your subject as well as focal length, but the idea still remains that by using focus peaking, you can be more critical in where you decide to set your focus point, again allowing you to avoid shooting at extreme apertures that aren’t as sharp when they aren’t needed.
Focus Peaking Basics
How do you use this amazing focus peaking option on your fancy new camera? While all cameras are a bit different, the basic idea is the same. Usually, you can choose both the color and strength of the peaking overlay display. I tend to choose red, but, depending on the subjects you like to shoot and in what types of light, other colors may work better. As far as strength or brightness level, the strongest settings are the easiest to see but can also be distracting when you are composing your shot. There is also the potential that weaker display levels of focus peaking make it easier to be precise when working with shallower depths of field.
Often cameras have the option to have focus peaking activate only during manual focus, or—even better—only when you push a custom button. That way, you can use it when needed and hide it when you don’t. In addition to using it in manual focus mode, I have it set on my Nikons to activate when I override autofocus by turning the focus ring while in an autofocus mode.
Having adapted from film to digital, and now to mirrorless, I will say fine tuning my focus peaking skills has been a slow process. Very quickly, I could see the potential, but mastering it to take full advantage of the benefits has taken me some time. So, if focus peaking is totally new to you, give it practice and don’t get frustrated. It is well worth the time invested. I would say for a landscape photographer, it is almost an imperative if you want to be at the top of your game.