I bought a Teleconverter Tamron-F for my sister's Sony alfa300. I paid it really a few euros, because it was in the box of the not working pieces. But the lenses were perfects so I decided to take it and try at home. When I tried it on the camera I've seen it doesn't transmit the autofocus at the lens.
I had thought the problem was in the gears inside the converter, but they were perfect. So I measured the little AF iron tooth on the camera and the groove in the converter and I found they were exactly of the same dimension (1,3 mm) so it's not strange that the tooth doesn't fix in the groove.
So I decided to enlarge a little the groove. I show you how to do that.

Step 1:

This is the tooth on the camera body:

do you have pics of the groove post-filing?
Hi Amanda, the groove you see in the photo is already filed. Anyway the filing is so light that it's difficult see the difference.

About This Instructable


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Bio: I'm an Italian freelance structural engineer, graphic designer and photographer. I'm also investigating electronics, robotics and science in general. I enjoy hacking and ... More »
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