Metabones firmware update for Canon EF adapter improves compatibility with Sony A7S

A7S with Metabones Smart EF adapter

Update on the update: Firmware update app is currently Windows only, Mac version available within the next 24hrs

Metabones have announced a firmware update for their Smart EF Mark IV adapter (E-Mount). This is a must-have update for A7S users who have experienced buggy behaviour with their camera using Canon lenses.

The firmware update is available from Metabones here along with full instructions.

If you have the earlier Mark III version of the adapter the firmware update must be done back at base. To do this users should contact Metabones to arrange the return.

There’s still some Canon lenses that experience issues on the A7S. The Canon 70-200mm F2.8L Mark II for instance fails to communicate with my A7S on the Mark III adapter far more often than my other Canon lenses. Metabones are working on an individual fix for this lens. It’s an incredible piece of optics and I use it a lot for the range and the excellent stabilisation it provides, so good to see a fix for it.

The update does not apply to the older Mark I and Mark II versions of the EF > E-Mount adapter from Metabones as these aren’t 100% physically compatible with full frame FE mount cameras.

To help Metabones test for other issues, do feel free to try the firmware update and share your own compatibility results on the EOSHD forum here.

A7S with 50mm F1.2L