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When is manual focus better than autofocus?
Perhaps this question has been asked before. I understand that in some cases, automatic focus cannot be used, for example, fast moving objects or people.
However, I have the impression that in all other cases (unless someone is trying to obtain a particular effect) automatic focus is better.
Any thoughts?
Manual focus is often used in situations where you need very accurate focus on a very specific part of the image, for example, for macro photos where the depth of field is so small you can't even get the entire subject in focus.
Another situation where manual focus is used when auto focus just doesn't work, usually because you don't have enough light.
And a third common use is "focus trap", you pre-focus on a specific spot, switch to manual focus to avoid the camera changing focus and wait for your subject to arrive at that spot.
For fast moving subjects auto focus is actually much better because, with any good camera, auto focus is much faster than manual focus and the camera has a tracking mode that it used to follow moving subjects.
Auto-focus is better in most cases simply because manual focusing with an high-resolution camera is pretty difficult or time consuming (at least with a camera up to entry-level DSLR range, never had an high-end DLSR to try manual focus on)
note: the above does not apply to rangefinder style cameras, those are usually designed for manual focus
Depending on the quality of the lens you are using, manual focus can often be used to achieve a more perfect focus.
Poor lenses often autofocus in a sloppier fashion, rendering the photo slightly blurry.
Also, if you have a DSLR with video recording capabilities (like a 7D) autofocus becomes painfully slow, and less precise during video recording, rendering manual focus very useful.
In addition, using certain extender tubes, and macro tubes can cut off the ability to autofocus and you would be forced to focus manually.
In macro shooting, manual focus is often a requirement for good shots, since you must focus very precisely.
But for just casual shooting, autofocus is quite a bit easier for most people, while in professional shooting manual focus tends to be used more since it has a greater amount of flexibility and customization.
