If that’s happening to you, and you haven’t focus fine tuned that long wildlife lens to your DSLR body, spend the $5.50 for a cheap Lens Focus Calibration Tool (it’s a foldable piece of cardboard with patterns printed on it), and Google “how to focus fine tune [your camera model].”
Many people who benefit from this article are going to be out there with their first new-to-them long lens (say, 500mm), and they’re going to wonder why they keep missing focus, even on shots where the subject was still. Nobody seems to care much about focus fine tuning until you whip out a 500mm lens and try shooting it wide open, but it is quite common for long lenses to need to be fine tuned to match the DSLR body. If you are shooting gnatcatchers at 15 feet and your focus is off by half an inch, most of your shots will be garbage. If that’s happening to you, and you haven’t focus fine tuned that long wildlife lens to your DSLR body, spend the $5.50 for a cheap Lens Focus Calibration Tool (it’s a foldable piece of cardboard with patterns printed on it), and Google “how to focus fine tune [your camera model].” It is the second best bargain in wildlife photography (after the low, low cost of reading photographylife.com).