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Keep Your Entire Photo in Focus With Hyperfocal Photography
An important part of taking a great photo is deciding what you want to appear in (and out of) focus. Often, you'll want to emphasize your subject by keeping the rest of the scene out of focus, so I've explained how to be selective about focus using your camera's aperture setting.
There are also times when you want everything in a photo to be in sharp focus, however, from the very front of the foreground to the most distant part of the background. There's a way to do this, and it's called hyperfocal photography--or, more to the point, shooting at your lens's hyperfocal distance.
The Problem With Focusing Normally
The term hyperfocal might sound a bit intimidating, but don't worry: There's no calculus or physics involved. The easiest way to understand hyperfocal distance is to imagine that it's the distance at which you need to focus your lens in order to get the deepest possible depth of field. Photographers often rely on the hyperfocal distance to ensure everything is in focus from the very foreground to the "infinite" background, as in the photograph linked here.
Consider this: Suppose you are taking a landscape photograph and want to include both a log lying on the ground in the foreground and some distant mountains. The log is only a few feet away, but the mountains are miles away--as far as the lens is concerned, they're at "infinity." Is it possible to get both extremes in sharp focus? Maybe. But how?
You already know that you should switch your camera to Aperture Priority and dial in the biggest f-number you can, like f/22. That setting gives you the best depth of field.
Suppose you focus on the log. Your depth of field extends in front and behind the log. The depth of field in front of the log is wasted, because you don't care about capturing anything in front of the log. Behind the log, you'll have some sharpness, but it probably won't go all the way to infinity.
Photography trivia: The closer your focusing distance, the more narrow your depth of field will be. This is why macro (very close-up) photos have such a miniscule depth of field.
Okay, focusing close didn't work. What if we focus more distant--on the mountains--by setting the focus on infinity? We automatically get deeper depth of field (because depth of field gets proportionally bigger as you focus on more distant objects), which is a good start. But again, we're wasting perfectly good depth of field. All the depth of field beyond the focusing distance is useless, since it's already at infinity. If you're lucky, the depth of field in front of infinity will reach all the way back to the log, but it's unlikely, especially if the log is quite close to you.
The Solution: Use the Hyperfocal Distance
You can probably guess where this is going. Instead of focusing on either the closest or most distant part of your scene, you should focus on something in between. If you pick the right place in the middle to set the focus, the depth of field will extend forward to the log and back to the mountains, rendering your scene perfectly sharp. Consider this photo. Rather than focusing on the grass at my feet or the mountains in the background, I chose an intermediate spot, which allowed the entire scene to be sharply focused.
So what's the right middle point to focus on? This is where the hyperfocal distance comes in. Specifically, the hyperfocal distance will give you a depth of field that extends from approximately half the focus distance all the way to infinity. Since the hyperfocal distance gives you the deepest possible depth of field, it's a photographer's go-to setting for getting a photo with seemingly infinite depth of field.
Here's a practical example: Suppose you know that the hyperfocal distance for your lens (at a particular f-stop) is 20 feet. If you focus on something 20 feet in front of you, everything from 10 feet away to infinity will be sharp. So to capture the log in our original example, you'd need to set your camera lens to its hyperfocal distance and then make sure the log was halfway between you and the point you're focusing on. That's all there is to it.
As an aside, here's a detail you might not care about, but I'll throw it in for thoroughness: Photographers have traditionally used a rule of thumb that says the depth of field at the hyperfocal distance goes from half the focus distance to infinity. In reality, that's not quite true. The near limit of the depth of field is not exactly half the focus distance, but it's generally fairly close.
Now that we got all of the theory and background out of the way, you're no doubt curious about how to actually determine the hyperfocal distance so you can go take some photos. Check in next week for the details.
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