All four lens that don't work exhibit the same behavior - it just locks up the camera after one shutter actuation. It never actually takes the picture.
Yes, that's exactly what happens to my 5D III. I replied to Kenko with list of lenses that did not work, and I just got their reply, which is not encouraging since it does not seem like they even want to look into it any further despite multiple user reports. So far I have not seen 5D III owners who report that ALL their Canon lenses work with Kenko, yet Kenko reports their 5D III body copy works with all the lenses. Hmm, is it possible that Kenko's Japan version of 5D III is fine but U.S. version isn't?
Thank you very much for your reply.
We have checked all lenses you mentioned with Canon 5D Mark 3 and Teleplus PRO300 DGX 1.4x Canon.
And we haven't any problems in these combinations.
Canon 135 f/2L
Canon 85 f/1.2L II
Canon 100 f/2.8 L
Canon 35 f/1.4 L
Kenko International Division"