Ambient Wireless TC Slate - ACD 301 RF - Manual (Page 17)

17
2 Operating modes
2.1 Generator Mode OFF
4 5 ON
The Clockit master slate contains a very accurate time code generator which
drives the display. When the slate is synchronised to a film camera or Nagra
recorder, the time code will not drift off more than 1 frame in 10 hours*. Other
time code machines which do not have such accurate Time code generators
such as DATs and video recorders may have to be synchronised every hour.
We recommend the Lockit box as an accurate time code and video sync
source for audio or video recorders.
*Note:
Clockit units running together do not drift apart more then 1 frame in 24 Hours.
When Clockit units are used in combination with other time code equipment
calibration errors can lead to increased TC-drift necessitating re-jamming more
frequently.
The Clapping sequence is as follows
Open slate - The Time code is displayed
Close slate - The Time code is frozen for 3 frames, then the userbits are
displayed for 3 seconds.
When switch 7 is ON the clapped time is displayed for 2 minutes at reduced
brightness after the userbits are shown. This value can be logged by the
Continuity/Script person.
Traditionally the time code in the master slate display is used to represent the
time code in the audio machine for syncing purposes. It may or may not have
the same frame rate as the film camera. The frame rate should be chosen so
that the 00 frame point in Recorder and camera is identical, assuming no time
code error. See the following table:
Film Camera fps 24 25 23.98 30
Video Camera fps 25 29.97
Master Slate
NTSC Video fps 30*
29.97 30* 29.97
PAL Video fps 25 25 25
* Dat recorders MUST be "pulled up", in other words run at 30 fps instead of
29.97 fps. The word clock will run faster in the recording process and be
pulled down to 29.97 fps to run in sync with the Telecine which transfers the
film, which was shot at 24 fps at 23.98 fps to be in sync with NTSC colour
video at 29.97 fps.
Note 1: The use of drop frame codes in the recording process is not recommended .
Note 2: Some filmcameras have a 23.98 fps frame rate. Audio recorders can then
use 29.98 fps TC. Recordings can then be synchronized with the Film (shot at 23.98
fps) without the need to pull down during the TeleCine process.