Originally posted by Marc Sabatella Practice on a sheet of text. Pay close attention to which lines look in focus in the viewfinder versus which lines appear in focus in the actual shot - it is unfortunately normal that more will look in focus in the viewfinder. Then work on using this information to help you "place" your subject within the focus zone. As you turn the focus ring, pay attention to whether focus is behind or in front of your subject, and get a sense of where the range is that might be in focus. If your tests with text show you that you need to have your subject toward the *front*of that zone, then make it so; similarly if your text practice shows you that you need your subject to be toward the rear of the zone, or right in the middle. On my camera, it needs to be toward the front.
Do this enough and you can get to 2 out of 3, maybe :-). Also consider buying an O-ME53 viewfinder magnifier, which helps a little (makes a a bigger difference, I find, than I'd expect given the relatively modest magnification), or if you really want to invest in MF, a split prism focus screen.
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I use a variation of this technique also.
Additionally, if your eyes aren't doing the job, try using the in-focus indicator light. Use trial & error to try to determine if there's a consistent 'spot' in the degree of focus throw the light is most accurate - right when it appears, in the middle, right before it turns off. With most lenses, this entire 'light-on' throw range will be only a couple degrees.
When all else fails, focus-bracket. Snap once at the appearance of the light, once in the middle, and once at the very end. One of those three will be tack-sharp.
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