Reviewing images from a rehearsal of the Ojai Art Center Theater’s production of And Then There Were None, I noticed three images that illustrate why we often end up with too much or too little depth of field in our photographs. Depth of field, as you know, refers to the range of apparent focus from foreground to background.
The images in this post were taken with different lenses at different times and from different distances. Two of the lenses were set to an aperture of f/2.8, while the third was set to f/2.5. This is not a scientific test, as the images have been cropped, and were taken from different angles under different lighting, but they still show us an important fact about depth of field. You see, every aspiring photographer knows that smaller apertures (e.g. f/16) produce greater depth of field and larger apertures (e.g. f/1.4) produce very shallow depth of field. But other factors influence the area and character of apparent focus, including focal length, sensor size, distance to subject, and distance from subject to foreground or background. It’s actually kind of complicated, and that’s why, unless I’m in the studio or really taking my time to set up a shot, I rarely get precisely the depth of field I would like.
Next week I’ll share more examples from this rehearsal to illustrate how too little, too much, or misplaced depth of field can dramatically alter our perception of an image. By the way, had I shot the first image at f/4 or f/5.6, I probably would have nailed it, except that it’s already at ISO6400, so I would have needed a slow shutter speed that would rob the image of sharpness through camera shake. I like the image very much, but it doesn’t suit the purpose of promoting the play.