Today I want to talk a bit about lens compression and how it affects portrait photography.
First of all let’s define lens compression:
Lens compression is the apparent compression of space between the foreground and background caused by a combination of changing the lens focal length and the distance from the photographer to the subject.
This sounds really complicated, but by the end of this post I will help you to wrap your head around the concept.
This effect can be used to your advantage in your images. With it you can control how close things in the background appear to be to your subject. By doing this you can isolate your subject against a less distracting background. I will show this effect later with a series of head shots taken with different focal lengths.
Before the photo examples I would like to show you a clip from the movie Goodfellas:
Notice how the scene outside the window seems to be moving closer and zooming in? This is lens compression in action! What is going on is the camera has a zoom lens, and through this clip the cinematographer is zooming in (increasing the focal length). The cinematographers is also moving back away from the subject as he/she is zooming in order to keep the subject the same size. If they hadn’t moved back while increasing the focal length, the camera would just be zooming in on the subject and the background would not appear to be moving closer. I can only imagine the complexity of planning a shot like this scene and the equipment needed to pull it off smoothly.
So how does this apply to portraiture?
Let me show you. Here is a series of head shots all taken of Sean at the park last week in the same spot.
I started with my wide angle lens and set it to 16mm.
I then moved to 35mm
A couple things to notice in this set of shots. The first thing is the distortion caused by using a wide lens vs longer lenses. The wide lens actually makes the person’s head look a bit thinner. This could come in handy if you have a client that would like to appear to have a less round head. The other thing to notice is the change in the background. Do you see how the bridge behind Sean seems to move closer to him with each shot? (Also notice the increase of bokeh) To make this happen I had to back up from Sean as I increased my focal length. You can really see the bridge zooming in in this animation:
And that’s lens compression!
I hope that I’ve helped you understand how this optical effect can affect your photography. If you have any questions feel free to comment below.
Thanks for stopping by!
Your photographer friend,
Joe: The Photography Guy