A Bit more on Autofocus

Posted by on Jul 22, 2011 in Articles | No Comments

So I was recently asked a follow-up question about my post on autofocus- What about ‘continuous’ vs. ‘servo’ setting in autofocus?

This is going to be an easy one for me to answer but probably not very satisfying for any of you. I have always used ‘continuous’ (or C ) when I am using autofocus or manual (or M) when I am manually focusing. ‘Servo’ (or S ) I found to be very frustrating early on so I have never used it since. Here is the difference: Continuous lets you take a picture no matter if the autofocus is locked on to something in your frame or not. Servo only lets you take a picture if the autofocus is locked in. My thinking is that there are times when the camera may think it is not locked but the resulting picture is great. Think about photographing a running animal or racing car or anything speeding past you (your youth, your cognitive abilities, pop culture). With continuous focus I just hold down the shutter and blast away hoping for (and usually getting) a good picture. With servo, the camera prevents me from taking pictures until it is happy.

I don’t know about you but I would prefer if I was happy first and not my camera. Besides, there are lots of times when some amount of out-of-focusness actually enhances your image. I am open to the possibility that servo may be useful in some circumstances, I just can’t think of what those circumstances might be.