APERTURE & F-STOPS

The photo on the previous page exemplifies the intentional use of blur. Even though these rivets on a door in Cusco, Peru, are rather close together, a very wide aperture (i.e., small number, f/2.8) creates this very shallow depth of field.

Similarly, the above photo features a lemur in Madagascar with an artistic and pleasing blur surrounding the subject. Because the leaves and other branches are at a greater distance from the photographer than the lemur is, a wide aperture allows for a more narrow (aka shallow) depth of field, yielding a nice blur to the non-important parts of the photo. This allows the viewer’s eyes to be drawn to the main subject – the fascinating lemur (Coquerel’s Sifaka species).

The exact aperture setting or f-stop that will yield such blur is going to depend on many factors. How far away your camera is from the subject and how far away the various parts of the scene are from one another are primary considerations. For instance, if you want to blur branches around an animal (e.g., the lemur photo), the branches need to be outside of the plane of focus by a reasonable amount. The word “reasonable” is ambiguous and so is the exact blur you’ll get from one scene to the next. Practice is truly the only way to get a decent handle on ratios from camera to subject to background, etc.

Aperture settings go the other way, with bigger f-stop numbers allowing more of the scene to be in focus. Rather than go into a physics lesson here