Rick Sammon's Exploring Photographic Exposure

4Especially Important Exposure Triangle Settings

There are several situations in which paying extra attention to your aperture, shutter speed and ISO are important. For now, let’s take a look at just a few. I’ll cover more situations later on in this book.

When photographing with telephoto lenses and when depth-of-field is important—As the focal length of the lens increases depth-of-field at any given point, aperture decreases. In the first rockhopper penguin photograph, taken in the Falkland Islands, I wanted to get the animals’ bodies, especially the eyes, in sharp focus while blurring the background. Because I was using my Canon 100–400mm ...