Syncing The Sensors Of Two Cameras - ARRI ALEXA Series User Manual

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12.4 Syncing the Sensors of Two
Restrictions: None.
Cameras
Two ALEXAs can be synced for 3D applications or any application
requiring sensor sync using the EXT connectors and corresponding
cable. When synced, images are captured from each camera's sensor at
precisely the same time. Sensor syncing is not available on ALEXA HD
and ALEXA HD Plus models.
Note: Syncing two sensors is possible at frame rates between 1.000 and 60.000
fps.
To sync the sensors of two ALEXAS:
1. Connect an EXT cable KC 155-S to the EXT ports on each ALEXA.
2. In the System menu on the master camera, select External Sync.
3. On the EXT SYNC screen, set Sensor sync to EXT master.
4. In the System menu on the slave camera, select External Sync.
5. On the EXT SYNC screen, set Sensor sync to EXT slave. It takes
approximately five seconds for the two ALEXAs to sync.
The master camera triggers the slave camera so that images are
created at the same moment of time with an accuracy of 10 µs.
Whenever an error occurs, the camera will issue a warning.
Image integration between master and slave camera has a locked offset
of less than 10 µs. This means that in the worst case, exposure differs
by 4.3% (@ 60 fps frame rate and 5.0° shutter angle). With a regular
exposure time (24 fps, 172.8°), the maximum difference is 0.05%.
Synchronizing Image Output
The REC OUTs and MON OUTs of two ALEXAs can also be
synchronized. To achieve this, the user must send a trigger from the
master camera to the slave camera after sensor sync is established.
To sync the REC OUTs and MON OUTs of two ALEXAs:
1. Ensure that the sensors of the two ALEXAs are synced.
2. In the System menu on the master camera, select External Sync.
3. On the EXT SYNC screen, select Send HD sync trigger.
4. Press the jogwheel to send the trigger to the slave camera.
The camera will display the message HD sync trigger sent to slave
camera!. If the sensors are not synced, the camera will display the
error message Trigger not sent. Camera must be set to Ext sync:
Master!.
After the sync trigger has been sent, the slave camera will no longer
display the warning HD outs not synced. Trigger now!.
Operation of the Camera