Dear users and potential purchasers of Tamron products.
Thank you for continuous use of Tamron products.
We would like to announce that following symptom were found when using our 18-400mm F/3.5-6.3 Di II VC HLD (Model B028) lens on Canon EOS R7/ EOS R10 used with Canon “Mount Adapter EF-EOS-R”.
Depending on the timing of camera power on/off, AF may not operate properly when the shutter release button is pressed halfway.
How to recover
Turn off the camera, remove and re-attach the lens, and then turn on the camera again.
We will continue to work on updating the firmware to match the mentioned cameras with remining lenses.
Please watch for further announcement on updated firmware.
We sincerely apologize to all users and potential purchasers for any inconvenience this issue may cause.