Tamron issued a notice about the 28-75mm f/2.8 Di III RXD (Model A036) lens focusing issue - it can be fixed via a firmware update (expected to be released in two weeks):
Notice about 28-75mm F/2.8 Di III RXD (Model A036) Operation
May 31, 2018, Commack, New York
Dear Tamron product users and potential purchasers.
Thank you for your interest in Tamron products.
We would like to announce that we discovered some issues with the auto focus of our new lens, model A036FS; 28-75mm F/2.8 Di III RXD for SONY mirrorless cameras, released on May 24, 2018. The issues occur primarily when using the camera in video recording mode.
Rest assured, we are evaluating the cause of the error and for the solution to this matter. We expect this issue to be resolved very shortly and we will release a firmware update at that time.
Regarding the firmware updating process, please be assured that the process is accomplished directly through the SONY camera and supported by the Sony firmware updating function. As soon as the process is finalized, we will explain the process in detail on our website.
We sincerely apologize to all users and potential purchasers for any inconvenience this issue may cause.
Here is an updated list of Tamron 28-75mm f/2.8 Di III RXD lens reviews:
The Tamron 28-75mm f/2.8 Di III RXD lens is currently available for pre-order at Amazon, Adorama, B&H and WEX.
After it was delayed, the current shipping date for the US is mid-June 2018.
Deal: the Tamron SP 45mm f/1.8 Di VC USD full frame DSLR lens for Nikon and Canon is currently $200 off.
Via Tamron USA
