Originally posted by Tony3d I think my problem is I don't understand how the multi point system works. It seems to me if I just point the camera at the subject I want in focus what's the advantage of having a ll the points, and possibly having it select the wrong subject?
Everyone develops their own favorite way of focusing. The AF system is AI; it's not psychic. So as the photographer, depending on what you're shooting, has to decide what option is best for what you're shooting.
With the AF multi-points, the camera is guessing based on how it was programmed. There are many situations that will confuse and fool it such as shooting through leaves, a fence, a screen, etc. With a quick shift lens, you can either manually tweak the lens to correct it, or you can use the four-way controller to select the correct AF point. Personally, I'd rather miss the shot because of my own lack of anticipation and skill, so I usually focus manually.
Using the center focus spot is fine if your focal point is always going to be in the dead center of your frame, or your prefer and have time to pre-focus with the center focus spot and then hold it in AF-S and recompose before shooting. The DSLR is designed to give you as many options, both manual, semi-automatic, and fully programmed as possible, and if you don't want or need those options, you may be better off with one that is designed to be used in auto mode.
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