The ALEXA 35, ALEXA Mini, Mini LF, and AMIRA cameras can directly accept, and be synchronized to a tri-level or black burst genlock signal. Once synchronized, an offset to the incoming genlock (shift sync) can also be applied in-camera.
Further explanation on why you need to apply a shift to the synchronization illustrates this document on Snyc Shift & GenLock.
For other ALEXA Classic models, such as the ALEXA SXT, ALEXA LF, and ALEXA 65, the camera can be synchronized to an incoming...