Focus speed.

[MarkST]

Hello.

I normally take photos of radio controlled cars at the local rc track. I am using a Canon 300d and a Sigma 70-200 2.8 APO HSM. I was just wondering, is the 300d holding the lens back in how fast it is focusing? The reason i ask as when i take photos the lens seems to take an age to focus on the subject.

By time i focus on the action, it has already passed. I also dont like to pre focus as the cars move quite fast.

So, how much faster would say, a 20d focus with the HSM lens than a 300d?

Thanks for any help, Mark;.

 

[SDK^]

R/C cars move pretty fast and the 300D doesn't have AI Servo as standard (Firmware hack required). AI Servo would probably help at bit.

I haven't tried a 300D or non canon lens so maybe someone else can comment.

 

[Johnny|lucidcomposure]

Yes it is holding you back. You could try the AI Servo hack as mentioned above.

I dont know what that lens is like but with it being a F2.8 I would imagine it to be quickish.

I have attempted to shoot RC Petrol Savages before and its something you're going to require a few attempts at.

 

[MarkST]

Indeed. I have taken loads of pictures there in the past, its just that with every good picture i get, i get 10 bad ones and the main reason for the photos being bad is they are not in focus.

Thanks for the help so far, Mark.