What are the settings AF1 and AF2 on the EF 70-200mm f/2.8L IS USM?

SOURCE: I have a Canon EF 300mm f/2.8L USM Lens

Here is a link to many Canon products in PDF form: Canon Parts Lists


Unfortunately, the only 300mm 2.8 lens listed is the IS version

The procedure is not that complicated, but you need to pay attention to the connections on the circuit board. The mount is removed, and you need to remove the small screws that hold the connector board to the mount ring first.

I cannot do live chat due to I use a Mac, but I will monitor the thread if you have questions,

Kevin

SOURCE: Sigma AF 24-70mm f/2.8 EX DG macro (Canon) or Canon EF 28-70mm f/

I have the Canon 24-70 f2.8 L lens, and there's no way you could ever get me to exchange it for a sigma lens. There's no question that this is a very excellent lens.

Why are you considering the sigma lens?

SOURCE: looking for a manual

I coulnd't find a manual. I did see a detailed specification page here:
http://www.usa.canon.com/consumer/controller?act=ModelInfoAct&fcategoryid=150&modelid=9996#DownloadDetailAct

It shows no manual is available for the lens.

Sachin Gharat

• 28 Answers
• Posted on Aug 02, 2009

SOURCE: Canon EOS 1D won't "read" my 70-200mm Canon lens.

HI I AM SAGHA REPAIRER FROM MUMBAI. I THINK YOUR CANON I D HAS A LENS SENSOR SWITCH INSIDE THE BODY WHOSE PLASTIC STUD CAN BE SEEN INSIDE THE BODY MOUNT WHICH COULD HAVE BEEN WORN OUT WHICH GIVES THIS PROBLEM BUT THIS IS NOT SOLVABLE BY YOURSELF GET IT DONE FROM REPAIRER.DO REPLY ME AS SOON AS YOU GET IT DONE.THANK YOU.

SOURCE: Hi- purchased the Extender

You haven't stated which body you have but the AF will not work with the extender if the effective lens aperture is too low (remember that a 2x extender doubles the focal length but halves the effective aperture).

Canon's own website states: "Autofocusing does not operate if the effective maximum aperture is greater than f/5.6 (greater than f/8 on the EOS 1V and EOS 3)."