70-200 MKI Focus Issue

I have an issue that's kind of hard to explain....

Check out the video:

http://youtu.be/3g-cQGc_QWE

In this demonstration i show you how slow my Auto Focus is on my 70-200 2.8 mki, from Infinity to 1.5 is moves quickly, from 1.5 to Infinity the focus seems to get stuck. this also happens when shooting, if i shoot i need ot have the lens set to Infinity for the lens to focus quickly. When i have the lens on 1.5 and try to focus on anything, the Focus is SOOOOOOOOO slow, like if something is holding it back, but after about 60 seconds it finally focuses.........

DO i need to get this lens built, oh FYI, it's a Very old lens.... Date Code is "UL"

Do you guys think i should take it to a technician and just have this lens rebuild... ive been using it like this for over 3 years now, but after i tried my buddies 70-200 it was MUCH MUCH faster.. maybe it needs a little love.....

I can;t use this lens for sports because i'm missing alot of shots.... do to the focus issue, i need to have it on infinity in order to get faster focus.

I watched the video and I'm not sure what your trying to do? Why are you starting at 1.5 and seeing how long it takes to get to infinity? It seems to me your just moving the focus to random sections like 1.5 or 3 then pushing the shutter button and seeing how long it takes. So depending what its focusing on your lens will try to find something in focus and go to it. It won't focus to infinity if what your focusing on isn't that far away. Go outside and aim for something far away and see what happens.

Take Care,
Cheers, Patrick

The video is not informative. The lens AF'd at 1.5, then without moving the lens you want it to AF at infinity? On what? I don't see a problem, but I don't have a clue what is going on in the environment, either.

told you it's hard to explain....

If i manually put the lens on Infinity Focus, the lens will focus on anything REALLY fast at any Focal Length....

If i have it at 1.5, even in Super well lit rooms, and sunny outdoors the Focus CREEPS....

When testing out how fast focus is on any lens, with the cap on,holding down the shutter button the lens will HUNT for something to focus on,it will go from 1.5to infinity and from infinity to 1.5 fast (all my lenses do this)

make sense now? probably not.

Like this:
http://www.youtube.com​/watch?v=0GzylGLXjIU

I don't think what you are doing is a "real world" test. How fast do you 'need' the AF to be while the lens cap in on? Go outside. Put camera in AI Servo, use BBAF and hold it down. Now move the camera around, focusing on near, far, near, far. THAT is what you want the lens to do. AF with the lens cap on is not telling you anything. Although I have taken many-a quick snaps with the lens cap on, the IQ lousy and shutter times tend to be long.

EDIT: I just notice two more things. The lens you are using is not the f/2.8 (I), it is the non-IS f/2.8. Yours is a much older lens than the f/2.8 II in your reference video. And the other thing is the camera in the reference video is a 1Ds (III), and yours is obviously not. You may be comparing apples and rutabagas here. Full disclosure, I have never used a 2.8 II, a 1DS(III) or a 7D, I think that is what you have in the video.

You can't test the lens with the lens cap on. It will hunt forever because it can't find anything to focus on so of course it will go fast from 1.5 to infinity and back to 1.5 again. Your camera needs something to focus on in order to see how fast it is. As I said before go outside and focus on different things near and far. You will see your lens is fine.

Take Care,
Cheers, Patrick