Compression using telephoto lenses.

Telephotos are camera lenses that magnify an image relative to how you would see it by the naked eye. Also called long lenses, they are commonly used in sports and wildlife photography, especially those preceded with the word "ultra". I have several zooms that fall into this category; many of the wildlife photos you see in my blogs are taken with them. Outside of the obvious benefits of image magnification, telephotos have another property which gives them great value. This involves something called compression.

Compression is the term used to describe the effect that telephotos bestow upon a scene. In order to see compression there have to be two elements being photographed; a near one and a distant one. In the above photograph, the two major elements are the ferry (called the Seabus) in the foreground and Canada Place (with the large "sail" structures) in the background. If you look carefully you can see a second Seabus just to the right and much further back of the front one. They are different sizes because of their position relative to the camera. You can see how much larger Canada Place is when its size is compared to the distant ferry, but the ferry closest to the camera appears to be larger, almost as big as the iconic landmark making up the bulk of the background.

It all has to do with ratios. The key has to do with distances between the shooter and the various distant points. For example, in the above photo, the distance ratio between the second Seabus and Canada Place is almost the same and so they appear to scale. However, the first Seabus is much closer to the shooter than Canada Place is and so is magnified accordingly. If Canada Place is four times farther away than the ferry it appears at a one-fourth scale. The effect can be toyed with quite a bit by altering shooter position relative to near and far subjects and focal length. This is a powerful tool in photography as it gives license to alter visual relationships between subjects.

As a rule of thumb, I always pay attention to the background when photographing. Although the subject holds most of my attention, my movements will have a significant effect on the subject's juxtaposition to what is behind it.

Thanks for reading.     Ericspix     Eric Svendsen