Okay -this will be a hit and run post - but will check back later. 
Both my husband and I shoot Canon EOS digitals, I have a 20d and he has a 5d. We having been shooting some roping horse and rodeo type images. We've looked through the manual but can't seem to find how to set the SERVO function. Can someone give us the basic "Servo for Dummies" rundown?
Thanks for your help!

