I frequently point out to my students that there is no such thing as “manual” – there are many “manuals”. You can set (not sex) exposure manually. Or focus. Or flash power. Or focus point selection. And so on.
So today let’s talk about manual focus. When you you use manual focus?
If you are me, the answer is “fairly frequently”. Like when I was picking up lunch just now:
The full list of reasons can include:
- Because you like having control.
- Because your lens only supports manual focus.
- Because you are better than your autofocus system.
- Because you are doing macro shots and accurate focus where you want it is critical.
- Because the scene has no clear focus areas (your camera needs good light and good contract).
In my case, all of the above sometimes apply. The AF system is quicker, and pretty good; but I am pretty good also.
My front door, earlier today:
Which as you can see is sharp:
So try doing manual focus for a day. Set the switch on your lens to “M” and do it by hand.
The best technique is to go back and forth around the sharpest point, making the oscillations smaller and smaller. While this is slower then the AF system, it can rival, or sometimes exceed, its results, especially on full-frame classical SLRs, with their bright viewfinder and their clear sharp view. It is a little trickier on smaller-frame SLRs and on transparent mirror cameras like some Sony cameras, but it is still doable.
When do I not use manual focus?
- When the subject is moving
- Especially when I am using AI Servo/AF-C mode (the AF system keeps tracking the subject).
- When I am in a hurry.
But failing this, manual can be a good way to do it.
Oh, and my lunch? A Big Mac, and taken with the Canon 45mm Tilt-Shift lens – a lens which only has manual focus abilities.