Apple Cinema Tools 4 - Manual (Page 233)

Ink Numbers
Ink numbers, frequently used for workprints, are another method of encoding the edge
of film in order to track feet and frames. Ink numbers are added to workprints and
corresponding magnetic-stripe film soundtracks (called mag tracks) after the workprint
and the mag track have been synchronized. On transferred workprints, ink numbers are
easier to read than key numbers, and they provide a counting mechanism that is
synchronized for both the soundtrack and the workprint. Ink numbers are sometimes
called Acmade numbers because Acmade makes a machine that is used to print ink
numbers. Machines that print ink numbers are commonly rented or owned and run by
film crews.
The typical style of ink numbering is a three-digit prefix followed by a character or space,
followed by four digits representing the footage number, followed by digits representing
the frame offset. For example, in ink number 123 4567+08, “123” is the prefix and
“4567+08” is the frame number, indicating that the frame occurs at 4567 feet and 8 frames.
The ink numbers encoded on the film do not actually include the last part (the frame
offset number). Rather, the frame offset is calculated by the telecine and appears in the
telecine log.
The prefix may contain fewer or more than three digits, and the numbering technique
for the prefix is usually determined by an editing assistant. For example, the numbering
could be associated with the scene number, as in “042” for the footage in scene 42. Or,
the prefixes might represent daily roll numbers.
Window Burn
As part of the telecine transfer process (described in Transferring Film to Video ), the key
number is typically burned in to the video (along with the video and audio timecode),
helping to identify specific frames. The burned-in numbers are called window burn.
It is much easier to use Cinema Tools if you can see the key numbers. You can use
Cinema Tools without the window burn, but it requires more effort on your part to ensure
that edits are being tracked properly.
233 Appendix A Film Background Basics