Posted by Richard Hahn on April 7, 2009 at 7:08 PM
Good evening.
I just received my new 2x tc from B & H, like a kid getting a new toy. (After all the difference between men & boys is the price of their toys). I connect it to my Canon Xti & Canon 300 4.0 lens, turn it on and get MF on the camera screen.
I check the lens figuring that it got switched from AF to MF only to find it in the AF mode. I go onto the B & H web site and check the compatibility chart, which I did before I ordered the tc, and the chart says it will work in AF.
I call Canon tech support and was advised that the 2.0 tc will not permit my camera to work in AF. According to Canon only their high end full frame cameras will work in AF with this tc. So I called B & H to get a Return Merchandise Authorization number.
But before I send it back has anyone out there had any luck using the 2.0 tc in AF mode. I recall reading something about putting tape over the contacts. Thanks.
Your camera requires f5.6 for the AF to operate. Your 2xTC converts your 300mm f4 lens to a 600mm f8 lens. Your camera and that lens and a 1.4TC would work fine (420mm f5.6). To AF with you camera and a 2.0TC you need an f2.8 lens. To AF with the 300 f4 plus the 2xTC, you need a 1 series camera.
I've heard of folks putting tape over the contacts to fool the camera about the aperture reading, but AF would be slow.
Posted by Richard Hahn on April 7, 2009 at 8:51 PM
Buck,
Good evening & thanks for your reply. The Canon service tech told me what you said too. I have a 1.4 tc, but wanted to go for the 2.0 to get a little closer. Now that I have had a little time to cool down I know the smart thing is to send the tc back.
It just ticks me off to no end that Canon doesn't list these minor details on their compatibility chart. I plan to send them a letter and request that they refund my shipping costs, which I am smart enough to know will not happen, but at least I will went on them. Thanks again.
Canon does mention the compatibility issues in their lens manuals/brochures but not in their camera manuals which would be helpful for those just getting into their systems.
Discussion
3 repliesI just received my new 2x tc from B & H, like a kid getting a new toy. (After all the difference between men & boys is the price of their toys). I connect it to my Canon Xti & Canon 300 4.0 lens, turn it on and get MF on the camera screen.
I check the lens figuring that it got switched from AF to MF only to find it in the AF mode. I go onto the B & H web site and check the compatibility chart, which I did before I ordered the tc, and the chart says it will work in AF.
I call Canon tech support and was advised that the 2.0 tc will not permit my camera to work in AF. According to Canon only their high end full frame cameras will work in AF with this tc. So I called B & H to get a Return Merchandise Authorization number.
But before I send it back has anyone out there had any luck using the 2.0 tc in AF mode. I recall reading something about putting tape over the contacts. Thanks.
I've heard of folks putting tape over the contacts to fool the camera about the aperture reading, but AF would be slow.
Good evening & thanks for your reply. The Canon service tech told me what you said too. I have a 1.4 tc, but wanted to go for the 2.0 to get a little closer. Now that I have had a little time to cool down I know the smart thing is to send the tc back.
It just ticks me off to no end that Canon doesn't list these minor details on their compatibility chart. I plan to send them a letter and request that they refund my shipping costs, which I am smart enough to know will not happen, but at least I will went on them. Thanks again.