I have seen many articles and videos trying to explain “Lens Compression,” and even experienced and respected photographers can’t seem to get this right. There is a lack of understanding among many photographers on how lenses work. The lens compression myth never seems to die. Just to make it clear:, Lenses does not “compress” anything!
So what is the thing about “Lens Compression”?
You have probably heard these statements:
- A wide angle lens will distort facial proportions.
- 85mm gives a face perfect proportions.
- A telephoto lens will make background objects come closer to the subject you are photographing.
- A telephoto lens will flatten faces
All of these statements are false. Proportions, background objects and “compression” is the same whether you use a wide angle (not fisheye) or a telephoto lens.
How can that be?
We all know how easy it is to make those big-nose-small-ears portraits with wide angle lenses while we can make beautiful portraits with 85mm lenses. The thing is that this has nothing to do with your lens. An 85 mm lens does not have any “magical” feature that will make your models look like beauty queens. It is all about one thing: the distance to your subject.
If you shoot a portrait with for example a 24mm lens you have to move closer to your subject to get the same framing as an 85mm, but what will happen if you shoot with the 24mm lens from the same distance as you would with an 85mm lens?
The framing will, of course, change but what’s interesting here is that if you crop your 24mm photo to match the 85mm framing the photos will be identical (not considering real lens distortions like the barrel, pincushion, etc. Bokeh will, of course, be different as well).
Long lenses do not compress perspective nor do they magnify background objects relative to foreground objects.
Try it yourself
It is very simple to test this yourself. The easiest way is to set up your camera on a tripod and shoot the same scene with two different lenses (a wide-angle lens and a telelens). Now open both photos in an editing program and crop your wide angle shot to match the frame of the photo shot with the telelens (you must, of course, scale the 85 mm photo down a bit) and you can see that both photos are identical. You can also see my test in the video below.
(more text below the video)
By now you should understand that lenses do not have any “magical” features that make e.g. perfect portraits or funny faces.
Now, let’s talk a little about perspective distortion which does exist, and is often confused with “lens compression.” Perspective distortion is what happens when you, for example, move very close to a face to get those funny features with a large nose and small ears. So what about shooting with 200 mm and the background seems to be much closer to your model? It’s not, you have only magnified everything in the scene.
Lens compression does not exist in your lens. Perspective distortion does exist and is all about the distance and angle to your subject. Learn more about this here.
Perspective distortion is influenced by the relationship between two factors: the angle of view at which the image is captured by the camera and the angle of view at which the photograph of the subject is presented or viewed.
If you are looking for a lens mainly to shoot portraits 85 mm lenses would still be a good choice because it gives you that “perfect” working distance to your model.
Using a 24mm lens from the same distance would require a lot of cropping. Also, you would not be able to create that beautiful bokeh with a 24mm lens.