Problem with 500 II and 1.4 II T.C.

I have had a problem with the Canon 500 II lens and my 1.4 T.C. for months now.
The IS on the lens is giving me problems. Without the extender on it is a perfect IS system.
When I mount the extender on it and turn on IS it kinda jumps around internally and the pics are all bad.
Not all the time, mostly when I have it on a bean bag. It just goes bonkers.
No matter what shutter speed or whatever. With the old 500 IS I had it worked like a dream.

I was shooting in the jungle about two months ago and a man with a 600 II said he has had his IS replaced.
And it did not help the problem. He had the same problem.

Since I don't like extenders it is not a big problem but my warranty is out in a few months and I would like to get to the root of the problem.
Does the 1.4 III fix this problem. I currently use the 1.4 II version.

Gary I think it could be the IS and someone else I know had the same problem. If it's just a tad out of warranty then I would try and get it back into canon, they MAY do something, otherwise it's a bill. have you tried cleaning the contacts with a rubber?

Ah, perhaps I should have said 'eraser'. :bg3: :bg3: :bg3:

It sounds like it might be more of an electrical contact problem than an IS system problem else why only with the TC attached? If the pencil eraser does not do it try some Lens Clens on an old t-shirt on the contacts on both sides of the TC and those on the camera and the back of the lens.

I'll try that today.
Help much appreciated.
Gary

Been raining, finally got out and shot with it for a couple of hours and not one problem..... :)
Thanks, problem solved.

Just out of curiosity, was it just a case of cleaning the contacts?

Daniel, yea that is all I did. Been having problems for months. Strange I did not have the problem on my 300. I use that same 1.4 on it with no problems.
Must of been the contacts on the lens I guess... I've got an old Ford Ranger TD here i use for birding. It gets filthy daily. Mud and dust on the back roads here in Thailand. Not to good on my equipment either... :) Anyway saved me a trip to Bangkok.
Gary