I'm stuck in a pattern for creating a photo: A-mode, spot focus, spot meter, continuous auto-focus. Adjust ISO and aperture as I see fit. 99% of the time, I operate as above. I went into continuous auto-focus for my boys baseball games, and never switched it out. Is there a downside (other than battery life) for using it compared to single-autofocus mode? I tend to care about the spot I'm focusing on being metered correctly, damn the rest of the scene. But that doesn't always seem to produce desirable results. Also: My Sigma lens seems to be more picky/fickle about spot focusing compared to my Nikon kit lens. I'm wondering if a scene-focus mode (assuming enough DOF) would help it out.