One of the first concepts I learned about in portrait photography was “Lens Compression.” The common definition is that a telephoto lens will “compress” the foreground and background together. This produces a more pleasing portrait that doesn’t distort facial features while still drawing attention to your subject (and not the background). In this post, I’ll get into more detail as to what lens compression truly is (and isn’t) and discuss how it applies to other genres of photography, like landscapes.
Let me first clarify that lens compression doesn’t technically exist. There is no magic in a lens that changes physics and compresses a scene. The “compression” is a byproduct of your working distance from the subject. You can take advantage of perspective compression using any lens. Don’t believe me? Take a look at the image comparison below.
Can you guess which image of the Maroon Bells was taken with a wide angle lens and which was taken with a telephoto? These two images look nearly identical even though I used two different lenses at drastically different focal lengths (17mm versus 180mm) and simply cropped the wide angle version to match that of the telephoto version. What makes these two images appear similair is my working distance from the mountain, not the focal length of my lens. I stood at the exact same position at Maroon Lake for each photo. Still don’t believe me? Download the telephoto version and the un-cropped wide angle version for yourself, then crop the wide angle version like I did and compare the two. Better yet – attempt a similair test using your own equipment.
Now let’s try the opposite – capturing the same scene from different working distances. In the train images below, the top half was taken with a shorter working distance than the bottom half. Look how much closer the blue train (in the foreground) appears to the green train (in the background) when photographed from a longer working distance. If you understand the previous discussion, you’ll realize that it doesn’t matter if the two images were taken with the same lens and then cropped or if one was taken with a wide angle and the other with a telephoto lens.
The diagram below breaks down my setup for the close working distance photograph. There was an equal distance between my camera and the blue train (represented by line “a”) and the blue and green train (represented by line “b”). There was about twice that amount of distance between the green train and the background (represented by line “c”). This resulted in a wide angle for the blue train (foreground) subject and a large amount of background (represented by line “d”) being included in the picture, which I cropped out of the picture (represented by the horizontal line above the trains).
The diagram below breaks down my setup for the longer working distance photograph. The distance between my camera and the blue train (represented by line “a”) is much greater than the distance between the two trains (represented by line “b”). My camera is also much further away from the trains than they are from the background. The key is that my camera changed positions but the trains did not – yet they appear closer to each other, or “compressed,” in the photograph.
Both of these concepts are very important to portrait photography. While you can technically use a wide angle lens from a distance and crop in on your subject to avoid this distortion, a telephoto lens provides the same end result both faster and without loosing pixels due to cropping.
How I apply this concept to my landscape photography depends on the desired effect. Let’s look at some examples.
There’s at least 5 miles between the fence/gravestone you see above and the base of Elk Mountain (Sleeping Giant) in the background. However, I wanted to “compress” the scene together, so I stepped back, extending my working distance, and used a longer focal length (although I could have used a wide angle lens and cropped). This makes the cemetery appear to be right at the base of the mountain.
In the above image of the Nelson Art Museum in Kansas City, I got very close to the shuttlecock lawn art (and down on the ground) because I wanted it’s size to be distorted in relation to the museum. As you can see from the next image taken from a longer working distance, the shuttlecocks aren’t nearly as large as the first image would lead you to believe.
One other point I’ll mention is that these concepts apply equally to cameras of all sensor sizes. If you have a 1.6X crop sensor camera and stand next to someone with a 1.0X crop sensor camera, as long as your lens selection or post-processing image cropping allows you to frame the same scene, your perspective compression will be equal even though the full frame camera will be at a longer focal length.