Have you ever thought that your camera’s focussing ability might be a little off? Perhaps you’ve noticed that when you use a large aperture, the sharpest area of your image is not quite where you put the focus point. If that’s the case, then it’s likely that your camera or lens is suffering from front or back focussing.
We’re not talking here about an occasional, overall blurry picture, but one where the sharp point is a little bit in front of, or behind, where it should be, and that this is happening consistently throughout all your images. It will only be really noticeable when using a wide aperture, as the depth of field is much shallower and makes the problem obvious.
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