New Information about that phenomenon, which is not just a Tamron phenomenon anymore. A guy at the DSLR-forum replaced the Lens-IDs with an EF adapter and found out that the cross-type sensors won’t work on Lenses with the following IDs: 27, 30, 35, 37, 38, 193, 194, 195).
So Tamron was just unlucky by taking the wrong IDs.
The following Canon lenses are also affected:
- 27 = Canon EF 35-80mm f/4-5.6 (I)
- 30 = Canon EF 35-105mm f/4.5-5.6
- 35 = Canon EF 35-80mm f/4-5.6 II
- 37 = Canon EF 35-80mm f/4-5.6 III
- 38 = Canon EF 80-200mm f/4.5-5.6
- 193 = Canon EF 35-80mm f/4-5.6 USM
- 194 = Canon EF 80-200mm f/4.5-5.6 USM
- 195 = Canon EF 35-105mm f/4.5-5.6 USM
The Tamron 70-200 f/2.8 is also confirmed to have the issue with the 40D, 50D and 7D outer focus points not being crosstype.
A few days ago we reported some Tamron lenses weren’t using the outer crosstype sensors on the Canon 50D.
Tamron Europe has confirmed the Canon 7D and Tamron 17-50 f/2.8 VC also exhibit the same issue.
We’re still waiting for an official response from Tamron in Japan.