fastes telephoto

I have been asked to shoot some team roping and wanted to know what the fastes tele lens was. I have the 70-200 non is and thinking about the 100-400. I think I should use a zoom but didnt know if the 200 would be long enoug and if a lens such as the 70-300was faster on the focus. Thanks in advance for any shared knowledge on these lenses.

The fastest Canon tele is the 85mm f/1.2L
But I'm thinking that you want longer than 85mm?

Also I'm not sure if you mean what we usually mean when we say "fastest" , it sounds like you may be talking about focus?

For focus, the fastest Canon zoom is the 70-200mm f/2.8L IS

The fastest focusing Canon 300mm zoom is the 70-300mm DO which is unreal fast focus. But both of SIGMA's 100-300mm f/4EX and 120-300mm f/2.8 EX are better choices for fast moving action.

Thank you so much for the info, why is the sigma better choice?

Maybe I should say you are correct on the fastest focus question that is what I meant. I just need a zoom with some reach for fast sports and dont know if I should get the 100-400 or use my 70-200 non is with extender

Oh heck, if I had kids I'd sell one and get myself "the Eye of Sauron"(as dubbed by an FM'er) 200 1.8, I hear they're pretty good with a 1.4 TC even.

The 300mm Sigma zoom's I mention have larger apertures, which means faster shutter speeds to stop motion in action oriented shooting.
They also have very fast accurate focus. But there a little larger than you might think.

ya I checked the reviews on fm and they are pricier than I thought too. I just need to figure out what to get for sports as the summer is comming fast and I dont know if the lens I have with 1.4or 2.0 is what I want to do , due to IQ going down the drain.