Use Of Keykode With Low Tach Rate Flying Spot Telecines - evertz 4025TR Instruction Manual

INSTALLATION
numbering relationship is ambiguous except for A frame
pulldowns.
In 30 FPS NTSC or 25 FPS PAL transfers; see section 3.12.6
for a discussion of Field 1 dominant and Field 2 dominant
characteristics.
7. After you have made any adjustments, park the telecine with the
reference frame in the gate, and repeat steps 5 through 8 until
you have satisfactory results.
problems, recheck the accuracy of the numbers without
KeyKode. (See section 2.11.7.)

2.13.7 Use of KeyKode with Low Tach Rate Flying Spot Telecines

Cintel flying spot scanners have a feature called Scantrack which moves
the scanning patch around on the CRT to prevent premature tube burn-in.
This has the effect of varying the biphase to film frame relationship
throughout the transfer.
4025TR keeps track of the biphase counts relative to the film frame pulse.
When low tach rate telecines are used with their Scantrack turned on, the
4025TR cannot
compensation value required for KeyKode calculations.
introduce a possible error of ±1 film frame in the edge number encoding
when used with KK JAM set to PLAY or WINDOW. One of the following
methods may be used to overcome this problem:
1. Use a higher biphase tach rate. (10 cycles per film frame)
2. Turn Scantrack off.
3. Use the KK JAM ONCE mode. This works because the
4. Enable the Play-window function of the 4025TR by:
Use the Film Tab of the Configuration screen to set the Play window to 1.
When the Play-window function is On, a KeyKode jam will occur
when the error between the KeyKode number and the biphase
based number is greater than 1 film frame.
number that the 4025TR jams to when the telecine is first put
into Play is correct because the Cintel's Scantrack offset is zero
when started. During the transfer, it is normal for the KeyKode
status ERR display to show ±1.
information about the KeyKode status display) This is due to
the ambiguity in the instantaneous Scantrack value calculated.
Model 4025TR Film Footage Encoder Manual
In order to track the scantrack position the
properly determine
Cintel telecine's Scantrack offset is zero when it is first put
into play. (See section3.4.1)
a. Adjust the PLAY WINDOW parameter in the Toolbox
menu (SHIFT + SETUP) to a value of 1 FRAME.
b. Set the KK JAM mode to PLAY or ALWAYS.
If you are still experiencing
the instantaneous
The KeyKode
(See section 3.8.1 for
Page 2-37
Scantrack
This may