Michael: You might have heard people say that the camera adds ten pounds, or around four and a half kilograms if you want to get metric about it. And sure, it’s a cliché, but it also holds a bit of truth about the way cameras don’t quite capture the world the way our eyes see it.

A lot goes into taking a picture, but there are two main things that might make you think you look a little wider on camera. The first is the fact that most cameras are cyclopses: the lens is their only eye.

Most of us perceive the world through two eyes, where one can see a bit behind things that are directly in front of the other. Our brains stitch together the two images to give us a sense of depth. But a camera usually doesn’t have a second “eye” to see around something in front of it, like a face.

So, compared to your normal eyesight, your brain might think a face in a photo or video is wider, since it covers up more of what’s behind it than you’re used to. And secondly, you might think you look one way, but cameras have a different perspective. You’re probably used to seeing your face relatively close-up in a mirror, with your ears a couple centimeters back, and your nose a couple centimeters closer.

Since a few centimeters is a big fraction of that face-mirror distance, your face appears slightly longer and thinner. But cameras can be much farther away, making your face appear a little wider or flatter. Not to mention, each camera lens has something called focal length, which can influence how you and the background look.

A camera lens focuses incoming light rays so that they meet at a point, and form a sharp, clear image. Focal length describes the distance between the spot inside the camera where the light rays meet and where the sensor detects the image. And it’s usually measured in millimeters.

Shorter focal lengths mean you get a wider view of a scene. They can make closer things appear relatively bigger, and farther things appear relatively smaller, which leads to that same face-narrowing effect. On the other hand, longer focal lengths capture a more zoomed-in image, which you can use to take a photo from farther away, or focus on a smaller part of a scene. And if your subject is a person, they might look a little flatter or stretched-out.

So sometimes, the camera can seem like it adds ten pounds. But don’t sweat it – that selfie probably came out fine!

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