Old Canon EF 100-300mm not working with my DSLRs

I have the Canon EF 100-300mm f/4-5.6 USM which I purchased way back in 1992.

I connect it to my DREBEL and my 30D and it almost never focuses. When it does focus, it is very blurry around the edges and I really wouldn't call the center sharp as well.

Manual focus is no better.

I haven't tried it on my old 35mm camera yet.

Does anyone know about a problem similar to this?

Can it be fixed?

The closest authorized Canon repair place is 15 miles away. I'll most likely send the lens to them to have them take a look. Will post the out come for those who might be curious.

Here is what would've been my first sports shots. Even if they are small shots, you can tell how badly focused they are.

I was rearranging my camera bag this evening. I decided to take out my trusty Canon A2. For whatever reason I put the 100-300mm USM lens on it and guess what. IT WAS FINE! No problem what so ever. It focused well and man is it quiet.

So I have a 100-300 USM that works on my 35mm but not on any of my DSLRs. I was under the marketing impression that all Canon EF lenses work on the Canon DSLRs. Is this a chipping issue? do my cameras need to be rechipped or does my lens have to be rechipped?

What to do??

Call Canon I guess....

I have the 100-300mm EF lens which I used to use with my Elan IIe 35mm, which also works with my digital rebel just fine. I have yet to have any problems focusing, etc. I'd be interested to hear what you find out.

Have you called Canon? They have alsways been willing to answer my questions.

Lisa

Quote:

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Originally Posted by ltilley

I have the 100-300mm EF lens which I used to use with my Elan IIe 35mm, which also works with my digital rebel just fine. I have yet to have any problems focusing, etc. I'd be interested to hear what you find out.

Have you called Canon? They have alsways been willing to answer my questions.

Lisa

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I just got off the phone with Canon and he me told to send it out to service. He couldn't give me a straight answer probably because he didn't have one. Mentioned a possible need for calibration?

It's strange:
I tried it on my DREBEL and it was fuzzy without getting a focus
Used it on my 30D right after and it seemed fine
Brought it to the park the next day with my 30D and then acted just like it did on my DREBEL
Put it on my old A2 and it was fine.

I should just mail it out now. Will post the results.