About the 20D & AI focus V's AI servo

gus · August 5, 2005

Ive been invited to shoot some more race cars tomorrow (hope there is better light this time)

Is it best to keep the 20D on Al servo or Al focus to shoot both moving cars & stationary ?

I really have read about it in the manual this time andy ...promise but i cant see the use of Al servo if Al focus will switch back from moving to one shot automatically.

Gus.

Steve Cavigliano · August 5, 2005

Gus,

Ya got me mate

I confess that I've never used AI Focus

I've shot still and action using One Shot and still and action using AI Servo. Using One shot, you have to re-1/2 press between shots (can't continuously fire away). I see no issue (like oof shots) when using AI Servo to shoot non-moving subjects

I forget to switch back to One Shot alot of the time

This senility is bad stuff :lol

In theory AI Focus sounds good, but I don't trust the camera to figure out whether my subject is moving or not :uhoh Although, as when using AI Servo, the 1st pic probably wouldn't be too sharp anyhow.

See, I've written a couple of hundred words and haven't helped you one iota :lol4

If you get to check out AI Focus, let us know how it works

:

Good luck and don't get caught up shooting sheilas instead of cars....lol

Steve

Andy · August 5, 2005

Humungus wrote:

Ive been invited to shoot some more race cars tomorrow (hope there is better light this time)

Is it best to keep the 20D on Al servo or Al focus to shoot both moving cars & stationary ?

I really have read about it in the manual this time andy ...promise but i cant see the use of Al servo if Al focus will switch back from moving to one shot automatically.

Gus.

put it in ai servo ympb and show us the awesome results

gus · August 5, 2005

Thanks steve /andy...hey steve i got some info from your words so all wasnt lost mate.

Last question Andy...should i have one red dot in the view finder for focus or turn them all on for either still or moving car ?

All of last weeks shots in album if anyone is interested ...finally sorted. Tomorrow is historic racing so that will be different to shoot.

Ta Gus

Higgmeister · August 5, 2005

Humungus wrote:

Thanks steve /andy...hey steve i got some info from your words so all wasnt lost mate.

Last question Andy...should i have one red dot in the view finder for focus or turn them all on for either still or moving car ?

Ta Gus

Hi Gus,
I too have not spent any time using it, but the manual says that once it locks on, it tries to follow the moving subject. If I was going to try it, I'd put it on a single focus point so you know what it's going to focus on and it should (theory) track your subject. Good luck and looking forward to some of the classic racers.

Please let us know how it works

Cheers,
Chris

gus · August 5, 2005

Thanks chris...will give it a burl & see what i get.

Gus

ginger_55 · August 5, 2005

Hey, thanks for the thread, gus, I needed that info!

g

have fun shooting that thing!

gus · August 5, 2005

ginger_55 wrote:

Hey, thanks for the thread, gus, I needed that info!

g

have fun shooting that thing!

Im not with you G..

what thread is that ? My link is to an album.

Gus

PS...i always have fun

ian408 · August 5, 2005

Hiya Gus!

I use AI all the time for my surfing buds. Anything that really moves gets
it and it works well. But I've also got camera set for focus using the AE
button.

Ian

ginger_55 · August 5, 2005

Humungus wrote:

Im not with you G.. what thread is that ? My link is to an album.

Gus

PS...i always have fun

No, no, Gus, my needs were simple, but great. I needed to know which setting to put the darn camera thingy on. You know ai servo/focus/one shot, whatever.

I had it in the middle one, after not being able to follow birds with one shot. Then I read the manual, things got worse when I put it in the middle one. Both Andy and Steve told you to put it in the bottom one: al servo, I think it is. (I wonder if things will get even worse now. All these birders and their Nikon machine guns are driving me nuts. My dog don't hunt, so to speak, or my dog does, whatever. Now are you really confused. That is southern usa slang.)

That was the part of the thread I was talking about. The other was a link, and I hate to admit it, but I didn't go there. Just picked your brains and left, so to speak.

ginger

DJ-S1 · August 6, 2005

Funny, I was just looking for AI Servo info yesterday in comparing the 10D to the 300D. I found this discussion which is way more info than I know what to do with. The comments from Chuck (who apparently works for Canon) are worth reading.

gus · August 6, 2005

WOW thats great DJ...thanks

Well worth the short read.

Dixie · August 14, 2005

Humungus wrote:

Ive been invited to shoot some more race cars tomorrow (hope there is better light this time)

Is it best to keep the 20D on Al servo or Al focus to shoot both moving cars & stationary ?

I really have read about it in the manual this time andy ...promise but i cant see the use of Al servo if Al focus will switch back from moving to one shot automatically.

Gus.

Gus, I shot NASCAR Cup and Craftsman Truck for almost two years. I used a Canon 10D for most of them using primarily the EF 70-200 f/2.8 IS USM. I know that this is after the race you needed the info for, but here's what I learned through trial and error and maybe you can use it in future races.

Shoot the practice, time trials, and the races on AI Servo with center focus. Track with the race car and try to keep it in the center (comes with practice). I don't know the track that you usually shoot at, but most have poles, etc. that will tend to get in the way. I've found that with center focus and tracking with the vehicle, I rarely have focus problems.

I tend to shoot at 1/250th second and slower. I will sometimes go faster (1/500 to 1/750), but I rarely do because the slower speeds show the speed by having the background and foreground blurred as you pan with the vehicle. Additionally, the slower shutter speeds let the tires spin more and that is really good for showing speed. In the shots below, the center one was shot at 1/750 and the top one at 1/250 and the bottom one at 1/125.

For the pit stops, I will normally switch the camera to One Shot. I did it so much that switching became second nature and very quickly done. I was normally situated on top of one of the large tool chests next to were the crew chief ran the race so I was in the pits and very close to the pit wall. For those shots I use a EF 17-40mm and that's when I would would switch to one shot. As soon as the vehicle pulled out it was back to AI Servor and the 70-200.

Here are a few shots from the last two years. If you have any questions about shooting races just drop me a line and I will help if I can.

About the 20D & AI focus V's AI servo

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