The runup of a vtr is the number of frames that the vtr takes to get up
to speed compared with a theoretical instant start.
The Runup value allows the Pogle to park the vtr nearer to the In
point to compensate for this startup delay.
Then the Vtr speed override moves the machine exactly into sync if
needed.
Video disks will have small consistent runup values like 2.
Newer machines like Betacam and D2 will have consistent runup values.
If the runup is set exactly then no speed override is needed.
Older machines like one inch or D1 or audio will have variable runup
values.
1-3 frames early or late is normal.
The Vtr speed override will varispeed the machine during preroll to
ensure an exact sync.
Set the vtr locally to a 2 field CF lock, otherwise it may fight with the Pogle lock.