When it comes to lens selection, or more specifically focal length selection, some choices are obvious. If you’re shooting a really big wide scenic landscape and want to show it all at once, you need a wide angle lens. If you want to photograph a tiger (and not get eaten while doing it), you’ll choose a long telephoto lens. If you’re photographing tiny flowers or bugs, you’ll choose a macro lens. Pretty straight forward, right?
But what about portraits? The choice may not be so obvious here — although it may seem so once you look at some samples!
Here’s a self portrait with quite a wide angle lens. (No one wanted to volunteer for this test… I can’t imagine why!!) This is an 8mm lens on a Micro Four Thirds camera, which puts it at 16mm full-frame equivalent (and about 10mm on APS-C).
Yikes! That’s awful. My forehead is monstrous, my nose is practically poking through the lens, and the background is far too visible — we see too much background, and it’s mostly in focus (there’s very little of that lovely bokeh we seek in portraits). Even though this was shot wide open at f/2.8, you get the background mostly in focus because on a wide angle lens, your depth of field is considerably larger at any given aperture than it is with a standard or telephoto lens. And finally, while you can’t really tell here, the camera was mere inches from my nose to fill the frame with my face.
So the problems here are:
- Distortion of the face
- Too much background
- Background is too much in focus
- You have to get really close to your subject to fill the frame.
I’m sorry you had to see that. Now let’s try a standard focal length of about 50mm.
So much better! First of all, I stepped considerably farther away from the camera for this photo. You really don’t want to have to stick your camera right in someone’s face to get a nice portrait, do you? Second, look at the shape of my face. OK, I’m no supermodel, but at least I don’t look like an inflated balloon here. My face takes a much more natural shape, and I’m comfortable saying that’s what I actually look like.
Next, check out the background. It looks better for multiple reasons. First, we don’t see as much of it, allowing our attention to focus on the subject. Second, what we do see is much blurrier, aka we have better bokeh. This is shot at f/3.6, which is wide open on this variable aperture zoom lens. The focal length was actually 27mm, or 54mm full frame equivalent (about 34mm APS-C).
This fixes all four of the problems noted above. Success!
But, what if we go for an even longer lens? Will the photo look even better? Let’s take it up to 120mm full-frame equivalent.
Yeah, that does look even better! The face shape hasn’t changed much, but it is a little different. And the background is even less defined — both because we see less of it, and it’s more out of focus. This photo was shot at 60mm (120mm full frame equivalent, or about 75mm APS-C). Plus, the subject was even farther away from the camera, which can be very beneficial. This lets you do beautiful portraits at a distance. That’s great for street photography, event photography, or any situation where you want candid portraits where the subject doesn’t stop what they’re doing because you’re pointing a camera their way.
But going back to the background… why does it look so different, and so much better? This is an effect commonly called “compression”, however if you do a little googling on the topic, you’ll find that the idea of lens compression has been debunked and that it doesn’t actually exist! (F-Stoppers did an excellent article and video on the topic). What we used to call “compression” is simply that the distance from camera to subject has changed dramatically, as we just pointed out in the previous paragraph. The difference in distance between the background and the subject changed relatively very little, while the difference between the camera and the subject changed massively. Another way to think about it is to take a top-down view of the scene.
In the very simple illustration below, we see a camera and background that don’t change position, but the lens field of view (how wide of an area it sees) does, and the subject therefore changes position to maintain the same size in the camera’s view. The subject steps farther back so they appear the same size in the camera, and the background is also the same size — but we see much less of it.
In a real photo, that background could be a cityscape of mountains that are dozens of miles away, so the change of subject to camera is a much bigger than than that of subject to background. Either way, we can see the difference quite clearly.
All of this said, it doesn’t mean you CAN’T shoot a wide angle portrait. In fact, super close-up purposefully distorted portraits with a really wide lens — like the fisheye photo below — can be a lot of fun! If you have a favorite shot like that, post it on Instagram or Twitter and tag me @PhotoJoseph and add the hashtag #SuperwidePortrait — I’d love to see it!