ARRI ALEXA - Using Time Code

To Next Page

To Previous Page

Using Time Code 113

</line>

<line>

</line>

<line>

</line>

</framelines>

12.3 Using Time Code

The purpose of Time code is to ensure that each image stored on one

medium has a unique value through which it can be identified. By doing this

in combination with correct reel naming, which is toi ensure that each

storage medium used in a production has a unique name, each image

acquired in a production can be identified uniquely.

There are many different ways how Timecode can be used in a production.

The 2 most common ways are presented as examples.

External TC, Time of day

 Use: This format is often used on multi-camera productions with sync-

sound. The cameras are running on a sync-sound speed, which is

also the project frame rate. if done correctly, sound and image time

code should match and allow an easy alignment in post.

 Setup: The sound department acts as the Time code master, and

generates a Timecode which uses the Time of day as a value, and the

time base is the project frame rate. 24 hours of time will translate into

24 hours of Time code.

This Time code is fed to the camera via the LTC in. The camera must

be set to Ext LTC Free Run, and the project fps setting must match

both the sensor frame rate and the time base of the external TC signal.

Then the camera can either use Jam sync mode, in which it samples

the TC value once and then continues counting based on its own high-

precision crystal clock, and the TC signal can be disconnected from the

camera after jamming. This mode ensures stable time code with an

offset of less than 1 frame for 8 hours, after which the camera has to be

re-jammed. Or the camera can be set to Regenerate mode, where the

camera uses the TC value of the external TC signal. This ensures

correct CT for an infinite duration, but the TC signal must remain

connected to the camera.

Other manuals for ARRI ALEXA