I had a play with a technique for macro last night, it works and works well...
Basically, set the lens to Auto Focus, ensure the lens cannot achieve focus, and half press the shutter button. Once the lens has finished hunting, fully press the shutter button, the shutter won't fire however. Now move the camera slowly until the subject comes into focus. As soon as the camera AF confirm activates the shutter fires. I for a hit rate of 9 out of 10 like this. The 10th one, I'm not sure on, but I think it was down to the very very short DOF that macro at 2.5x lifesize gives....
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