Wide-Open/Custom Function Button (Focus Hold)

Assignable Custom Function Button

On modern (2015+) cameras, the button on the adapter serves as the assignable "Focus hold" button found on Sony G series lenses. You may for example assign "Aperture Preview" or "Eye-AF" to the the "Focus Hold" button and get the same DOF preview function as on a Canon DSLR. This assignable button function is not available on legacy cameras older than 2015.

1. Press MENU button of the camera.
2. Find 'Custom Key Settings' in the menus. Consult your camera's owner's manual on where to find it.
3. Set the desired function under 'Focus Hold Button'.

Wide-Open Function (Canon EF-Mount only)

On legacy (<2015) cameras, when the adapter is in Advanced mode, or the camera body is in Movie mode, the lens' aperture is set to wide open for ease of focusing while the Wide-Open (WO) button of the Metabones Speed Booster / Smart Adapter is depressed. Release the button and the lens will return to the aperture set on the camera.

This wide-open function is automatically shut off when you actually take a picture and during movie capture.

This wide-open function is unavailable when the Metabones Smart Adapter is in Green Mode.