In an announcement on its Japanese website, Tamron has issued a product advisory informing consumers that three of its E-mount prime lenses suffer issues that prevent them from using autofocus when shooting videos on Sony a7 IV camera systems. The 20mm, 24mm, and 35mm f/2.8 Di III OSD lenses, released in 2019, have an autofocus issue when paired with Sony’s full-frame a7 IV camera system that causes the lenses to switch from AF to MF when shooting movies.

Tamron hopes to fix the phenomenon, saying ‘We are currently investigating and will provide details on the “Support Information” page at a later date.’ Based on the problem, it would seem a simple firmware fix could address this issue.

More info on Tamron’s website.