Couple of weeks back, I discovered the power of manual focus, and now for each and every shot, I use manual focus!
Are there some situations where manual focus doesn't make much sense and we should allow the camera to do the job? Any examples would be helpful.
In sports/action photography, especially in good light conditions, the autofocus will (probably) manage to focus on the action much faster than you could. Thus manual focus would then make you miss shots.
Basically any type of photography that requires you to be very fast.
You should avoid manual focus if auto focus will have better chances of hitting. In addition to speed advantage already mentioned by @PimJager, your bad eyesight (e.g. missing eyeglasses), low light (where AF could use assist light) or (electronic) viewfinder where good focus looks hardly any different from wrong focus might give auto focus an advantage over you focusing manually.
Also, on some lenses the focus ring is either so tiny or has such a short run that they are not really comfortable for manual focusing.
On many compact cameras manual focusing is either buried in menu or missing altogether. If using manual focus is so clumsy you would give up taking some pictures at all, better avoid it.
I mostly use AF for common shooting, but I use center point only as the camera sometimes when using Auto-11 mode, decides to choose incorrect AF point.
However, manual focus needs enough time. I use it only for purposes, where the AF is not reliable - macro photo, also sometimes for static objects (when using tripod) etc.
But mostly use AF. :-)
Photography is art - whatever method helps YOU take better pictures is the best method for YOU.
You can even take sports photos with manual focus (proof: there were sports photos before there was auto-focus) - it's just more difficult and takes preparation and planning (and missed shots).
The auto-focus on modern DSLRs is very fast and nearly perfect in good light, it's also very predictable when it will fail (low light, macro, etc.) - so there is no practical reason not to use it, but, manual focus does force you to slow down and think about focus. If this helps you get better pictures - or you just enjoy it more - then go ahead and take all your pictures with manual focus.
Trying to do macro shots hand-held works better with auto-focus set to a tracking mode (e.g. AI SERVO on Canon).
