Focal Length and Field of View

To illustrate the dramatic difference in the field of view between different lenses, I left the camera on a tripod, and exposed three frames from the same spot with different lenses. This is the effect of zooming when we change focal lengths that most people are familiar with.

Keep in mind that a wide angle lens would also increase the depth of field; with a 24mm at f16, you can get everything from a flower a couple of feet away to distant mountains in sharp focus.

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Focal Length and Perspective

Now, let’s look at a less familiar effect of changing focal lengths: how telephoto lenses compress perspective and wide lenses stretch it.

For this series, I moved to keep the driftwood in the lower right corner about the same size when I changed lenses.

Notice how far apart the driftwood and the rocks apear to be in the wide angle shot, and how close together they look in the telephoto image.

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50 mm

300 mm