In nature photography – especially macro nature photography – depth-of-field (the amount of an image that is in-focus) is an ongoing concern. When shooting small subjects that are close to the lens, it seems that one can never get enough. Photographers are perennially trying to squeeze out just a little more, and to work within the confines of what they’ve got.
Shooting in low-light complicates the depth-of-field problem even further, and this is often the case when photographing small wildlife. Insects, salamanders, lizards and other tiny creatures are often found under the forest canopy where there is little sunlight. To compensate, the photographer may increase the camera’s aperture (f-stop) setting, which allows more light onto the sensor or film. This produces the undesirable side effect of reduced depth-of-field.
Keeping perpendicular to your subject mitigates the problem, but is compositionally and creatively limiting. Recently, some computer-savvy photographers have taken to digitally “stacking” multiple images to extend the depth-of-field. While this technique can generate remarkable results, it requires ample time spent in front of a computer and is not suitable for situations in which the composition is changing (for example, if the subject is moving or the camera is hand-held).
Perhaps it is best to stop thinking of ways to solve this problem, and concentrate on ways to work with it. There are several strategies in which a shallow depth-of-field can be used to the photographer’s advantage.
Isolating a Subject
Perhaps the most obvious and frequent use of a shallow depth-of-field is isolating a subject. In this technique one attempts to capture the entire subject in-focus, while allowing the background to be rendered out-of-focus. This permits the viewer to concentrate on the subject without being distracted by elements of the background. It also produces a blurred background (or bokeh) that is pleasing to the eye. This technique is amply used in bird photography, where there is often considerable distance between the subject and the background.
Isolating a Specific Part of the Subject
When the depth-of-field is extremely narrow, it can be used to pull the viewer’s attention to a certain part or feature of the subject. Our eyes are naturally drawn to the part of the image that is in-focus, accepting the out-of-focus elements as part of the background. When shooting wildlife, the in-focus element is nearly always the eyes or face. This can create an interesting and intimate portrait of the subject.
Framing the Subject
While photographers often direct their attention to the in-focus portion of an image, the out-of-focus portion can often play an important role as well. In some situations, it is possible to use out-of-focus foreground and background elements to “frame” a subject. Often, this isolates the subject completely from its surroundings and strongly directs the viewer’s attention.
Creating Artistic Images
There are undoubtedly countless ways that a shallow depth-of-field can be used to create artistic and provocative images. It can blur the lace-like wings of a dragonfly, or provide a new perspective on a caterpillar. Creativity and imagination are important tools here, and you never know what you might capture! Whatever your approach may be, the technique allows the photographer to guide the viewer through the image.
Next time you’re faced with too little depth-of-field, experiment! Remember that the human eye cannot focus on everything at once, and neither can the camera. Try different compositions and focal points, and think about how you want people to see the image. You might gain a new perspective on a familiar subject, or produce an interesting shot of a new one. Working with a shallow depth-of-field is a great way to turn an old problem into a new adventure!