Technique question: Focusing on moving subject

[Headshotzx]

Hello guys! I've been puzzled with this technique question for quite some time already. Here's the situation:

I've got my dslr AF-mode set to AI Servo, with either a 50mm f/1.8II (no FTM focusing) or another zoom (take a 17-40 f/4L USM FTM-enabled for this situation). How would you constantly keep the focus on a person running straight at you? With a 400D and 17-40mm, the focusing isn't exactly very fast, and once I've focused on his face by half-pressing the shutter, he's moved like another half metre towards me already. Don't even talk about the 50mm f/1.8 yupp..

Anyone know how do deal with this? This doesn't exactly affect me much, but I'd like this question answered. I know that a 1Dmk3 with fast prime lens will definitely do a better job at focusing faster, but lets say I'm limited with the equipment I have, how would I work around it? I know that for these kinds of situations, manual focusing will be better (that's also why FTM was made in the first place aye?), but is there any trick or function of the camera that'll help?

Thanks for reading, and hope to have a reply soon~

 

[raptor84]

For a wide lens the DOF should not render the face too OOF but what i normally do is to keep one focus point contnously tracking on the subject and shoot in a burst of 2-3 shots. If you use manual it needs a lot of practice to be able to judge the speed at which to turn the ring.. I get get 1/ 3-4 in focus shots froma running dog on my 350D and a 70-200 in good light so I think the 400D should have no issue.

OT abit but yea once you use the 1 series you get spoiled =p

 

[huggable]

Walk backwards, if he wasn't too fast.

 

[Headshotzx]

Walk backwards, if he wasn't too fast.

Yeahhh that's one way to get a shot while escaping from a tiger..

Thanks for the replies! I'm not rich enough or proficient enough to use the 1D yet xD

 

[huggable]

Oh well, that's what a "tan-jia" wedding photographer thought me, along with some other tips to get beautiful skies.

Worked very when I had to cover a wedding event myself!