Appendix 1

Finishing on Film
pixels wide (2,048 × 1,556 for full-frame 35 mm). The actual resolution of the 35 mm negative is
closer to 6 K. It is not possible to put the full 6 K on the screen, however. Even a fi rst-generation
print will only be around 4 K. Before digital intermediate, shots for digital effects scenes were scanned
at 4 K (4,096 × 3,112) on pin-registered scanners. Pin-registered scanners lock the negative in place
with several pins before scanning. This ensures that no unwanted movement or jitter will be added
in scanning. The process is slow, on the older scanners taking three to fi fteen seconds to scan each
frame. Scanning a feature fi lm this way takes more than a week. It also generates massive uncompressed
image fi les of 52 megabytes per frame requiring 7–8 terabytes of storage. Newer scanners
are much faster, produce smaller fi les, and are, therefore, much more affordable.
In an effort to reduce the cost by speeding the process, datacine machines have been developed.
Something of a hybrid between a scanner and a telecine machine, the datacine can “scan” in
real time at 2 K, or on some even 4 K. And the newest Spirit Datacine scans at up to 30 FPS. Unlike
scanners, most do not have “pin registration” but still produce a very steady image, yet small problems
may show up in composite effects. When two fi lm elements are overlaid, if they are moving
around in opposite directions, even by a tiny amount, the movement appears doubled and looks very
bad. For this reason, pin-registered scanners have always been used for effects compositing. However,
new compositing software can remove any movement introduced by the datacine by digitally tracking
any unwanted movement and removing it.
In telecine, most color correction is performed as the image is “scanned.” Because video formats
have a limited “color space,” there is more control over the image while the fi lm is on the telecine
as you can control the print light and color. While there is a lot of control over HD Cam SR or D5,
once the fi lm is recorded to any video format, there is less control over the fi nal look.
When using a scanner or datacine to record to 2 K or 4 K, it is digitized in either the Cineon or DPX
(Digital Moving Picture exchange) format. These are either 8 or 10 bit, although 10 bit is normally
used, and can have a fi xed color space or use a look-up table. (See Appendix 1 on digital video
formats.) So in these formats, it is possible to scan the entire fi lm onto the drives, with all color and
contrast information intact, and color correct later. In fact, the digital scan becomes a virtual fullframe
negative, allowing formatting and additional color correction for video release, high-def
broadcast, or standard broadcast. Also, because in most workfl ows, the entire shot is scanned fl ash
to fl ash, even recutting is possible. And, as a 2 K DI of a feature fi lm is under 2 terabytes, the entire
fi lm can be archived on removable drives. A 4 K feature is four times bigger, or about 7–8
terabytes.
Many of the systems used in the DI workfl ow cannot play 4 K in real time. The amount of data is
huge, and any processing of the data takes time. So some systems will only work with 2 K fi les.
However, the footage can still be scanned at 4 K. The 4 K is resampled down to 2 K, creating what
is called “enhanced 2 K.” While not looking as sharp as 4 K, it is much sharper than standard scanned
2 K. Keep in mind it is even more expensive than 4 K. It still requires a 4 K scan, plus, this needs to
be resampled, requiring hours or even days of computer time. But now color correction and conforming
can be done in less time and on more affordable systems.
With DI, there is a small loss of quality. Some subtle details in the shadow and highlights, which
can be pulled in when scanning and color correcting directly off of the negative, are lost, however,
the loss is small and the control and convenience, huge.
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