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The most important piece of information for organizing DPX media is the filename of
each frame, which includes the frame number that identifies the frame’s place in each
sequence. For later conforming in Color, DPX filenames must have a prefix, an underscore,
a frame number, and a file extension, taking the following form: Filename_0123456.dpx.
Another important piece of information for Final Cut Studio workflows is the name of the
directory in which each image sequence is located. Each image sequence should be
stored in a directory named with the number of the camera roll the image sequence was
scanned from. This is so the directory number can be used as a reel number during
conversion to offline QuickTime media, for tracking the correspondence between the
frames of the QuickTime media and the original film frames.
Additionally, metadata written into the header of each DPX file provides additional
information for image processing and media tracking. This metadata is typically written
by the facility doing the transfer and includes the following:
• Transfer: Specifies whether the image is linearly or logarithmically encoded. Scanned
film frames are typically logarithmically encoded, but Color can work with either linear
or logarithmic media.
• Low Reference: The numeric value used to identify the black point. For media being
printed to film, this value is typically 95 (for logarithmically encoded media).
• High Reference: The numeric value used to identify the white point. For media being
printed to film, this value is typically 685 (for logarithmically encoded media).
• Timecode: For compatibility with the Color method of reconforming DPX media to
match an EDL generated by Final Cut Pro, the timecode value written into the DPX
header should be derived from that file’s frame number. For more information, see the
Color documentation.
Backup and Archiving Considerations
Unlike workflows involving tapeless media, film-scan workflows ensure that you always
have a backup in the original camera negative. If something happens to your film-scan
media, you can always retransfer. However, this will be expensive, so it’s best to
redundantly archive all of your transferred media, preserving the directory structure you
created to organize your media. Hard disk backup to multiple volumes is a good short-term
solution, but optical or tape data backup may be the most suitable long-term solution.
Common Offline/Online Strategies
There are many ways of organizing an offline edit and online reconform of scanned DPX
media. One of the more straightforward ways of working with DPX or Cineon media in
Final Cut Studio is to use Color to generate offline QuickTime clips from the DPX or Cineon
source files. During this conversion, each clip’s timecode is derived from either the
timecode header metadata or the frame number in the filename, and the reel number is
derived from the name of the directory in which each transferred image sequence is
stored.
40 Chapter 2 Ingesting and Organizing Your Media