How Many Focus Points Should You Use in Landscape Photography
Recently, one of my photography workshop students (notice how I sneaked in the marketing of my photo workshops in the first sentence - my 2023 workshops are filling up) told a story about an experience she had while shooting landscapes. She was using a single-point autofocus mode when a man looked over her shoulder and told her she should be using a multi-point mode instead.
In photography, I seldom make a blanket statement about someone being wrong, but in this case he was wrong.
Here's why.
The explanation about why I think the man was wrong is because in landscape photography you want to control your focus point exactly. This is especially true with wide-angle shots where using a multiple-point focus mode might put the focus as much as a foot or more away from where it needs to be.
The reason can be explained with a tool/technique/calculation called hyperfocal distance, which helps you maximize the depth of field (DOF) in the shot. Depth of field is how much of the photo appears to be in acceptable focus.
Hyperfocal distance is a point some distance from your camera that gives you maximum DOF for an aperture and focal length. If you focus on that point, you'll get DOF from infinity to about half of the hyperfocal distance. Moving the focus off that point means that you limit your DOF and get suboptimal results.
You can see it below in the chart that comes from PhotoPills, a landscape photography planning application. The distance that the you focus at is in the left hand column on this chart. Where I highlighted is the distance before hyperfocal. You won't get the background in your DOF. The hyperfocal distance is next row in the chart. It shows max DOF. As you focus further away from the camera, you keep the background DOF, but you lose foreground DOF.
With a single-point autofocus mode, you can move the focus point exactly to the hyperfocal distance. With a multi-point mode, the camera is going to pick. Depend on the camera and the mode, it might pick the closest point or it might pick something else. In some cases, the point that it selects to focus on may be feet away which causes you to lose DOF.
Using hyperfocal distance in the field doesn't require a tape measure if you can estimate distances. I've measured the distance between my fingers when I've outstretched my arms and can use that as a measurement tool when needed. Luckily, I've been around a lot of tape measures in my life -- my dad was a contractor and I worked for him as a carpenter -- and have gotten used to judging distances visually. When on the job, my dad used to say that you should develop a calibrated eyeball, which is the skill of being able to judge distances and plumb and level with your eyeball before you verify it with a tool.
For photography, it's also a good practice to calibrate your eyeball to distances (and plumb and level). That allows you to easily judge distance to achieve hyperfocal distance.
As an example, I shot the below photo with a 20mm lens at f/13. Consulting the hyperfocal distance chart in PhotoPills shows that I needed to focus 3 feet and 6 inches away from the sensor to achieve focus from about 1.75 feet to infinity. The little rock point on the bottom right of the shot was about 3 feet and 6 inches away, so that's where I focused. That allowed me to get tack sharp focus at that point and DOF from 1.75 feet, which is just a few inches forward of the bottom left corner, all the way to the horizon and clouds.
Getting the focus point on the exact distance can be tricky in the field, but you do have a little leeway if you don't have an object in the photo right at that half of hyperfocal distance measurement. The rule of thumb is to move your single focus point to about the bottom third line. This works well when you are using a wide-angle lens (35mm or wider) at f/11 to f/16 and have the tripod at chest level or higher. When doing this, you are likely putting the focus point near enough to the hyperfocal distance that it'll be good enough. But, I'd recommend checking focus in the foreground and background and move the focus point towards you if the foreground is out of focus and the background is in focus and do the opposite if the foreground is in focus and background out of focus.
I used the same technique for the next photo of the waterfall. This time I shot the 20mm lens at f/16 (I wanted a slower shutter speed and because f/16 lets in less light than f/13 you have to go longer with your shutter speed to arrive at the same exposure brightness). In this case, the hyperfocal distance was 2 feet and 10 inches. That let me set up close to the foreground waterfall to make it look larger. In reality it's just about a foot and a half tall.
Related: I think that one of the reasons people do focus stacking is because they don't understand hyperfocal distance. For me, the only time focus stacking makes sense is if your foreground is closer than DOF for the hyperfocal distance or if your subject doesn't fit within DOF. Then it's optically impossible to get enough DOF and makes sense to do focus stacking.
There's a bit of a philosophical take on focus stacking though. Some photographers believe that everything in the shot should be tack sharp. Focus stacking will get you that (with a few issues to be aware of, such as moving vegetation). Hyperfocal distance gives you acceptable focus, which means that faraway objects aren't isn't going to be as sharp as they would with stacking. What ends up happening is the background might be a touch softer than the foreground. In my opinion that's a good thing. Because photography creates a two dimensional object, the photographer has to trick the viewer into believing that the photo is 3D. One way to do that is having the background acceptably sharp instead of tack sharp. That's what our eyes expect. We don't see faraway objects as tack sharp with our eyes.
And with that, this is why you probably don't want to accept unsolicited advice from random men when out photographing landscape. Or it's why you should use a single-point focus mode.
Much needed creative break
It's hard to describe my level of burnout and fatigue from the pandemic, home schooling, navigating health precautions, etc... To help address that, I've been taking a "break" from photography. A break for me is only going out and shooting once or twice a week.
I've found that when I'm feeling this way that taking a class or trying a new creative art helps. Last time I felt this way, I took a cartography course from Esri. This time I've decided to take up hand-drawn cartography. I've been making maps similar to this one to try and get my photographic drive back.
It's working. I've actually had more of a desire to go out shooting.
If you get to the point of photo burnout, pick up another creative pursuit for a spell. It might get you excited to get back out shooting.
Until next time
I hope that the explanations and techniques that I've written about here help you in the field. Also, I'd like to apologize. I'm terrible at proofreading my own work. Several people emailed me on the last newsletter pointing out mistakes. I'll make mistakes. That's for sure. I'll see you again in two weeks.