1 The Director of Photography – an overview

118 Practical Cinematography
Figure 13.2 The traditional
combined grey card
Figure 13.3 Kodak’s ‘Grey Card Plus’
When the laboratory prints the scene correctly to your 18 per cent
grey card, this will cause crushing of the highlights and lifting of the
shadows in the blue layer; this will remain since we chose a film without
the latitude to cope with it. The middle densities will return to the
correct position on the print’s sensitometric curve.
The above technique gives a very pleasing ‘gritty’ feel to a scene. It
is much more reliable than asking the laboratory to print for the effect
if they have the 18 per cent grey card to work to all the time.They will
produce the same effect on each day’s rushes providing you remember
to put a card on before each scene and tell them that you want the
following scenes graded to it.
Developments in grey cards
For many years, motion picture grey cards always came as a two-page
card folder, as in Figure 13.2. One page has a series of progressive grey
patches and the other page has a simple 18 per cent grey sheet. The
custom, particularly when filming for television, was to photograph
both pages simultaneously.
The grey card worked exactly as described above.The series of progressively
darker grey stripes was intended to be read by the telecine
operator as a stepped waveform. However, this did not really work. A
piece of card, however high the quality of the printing, will only reflect
from the whitest patch to the darkest patch a maximum range of four
stops and that is if it is perfectly lit. Clearly, this is not even the tonal
range of the television system, so does not really tell the telecine operator
very much.
The 18 per cent grey card, on the other hand, is a universally, indeed
internationally, known standard and therefore can be used as a means
of communication between the cinematographer and the laboratory
no matter what countries either or both are in. It therefore became the
norm to photograph only the 18 per cent grey card and more or less fill
the frame with it.
When filming for television it has become more and more popular
to transfer the negative directly to a videotape. This is increasingly
being done at the rushes stage, even on feature films, so that those
rushes can be transferred directly into a non-linear computer editing
system. It can also be a very high quality way of transferring a cut negative
to the final, graded transmission tape.
One problem with transferring the rushes negative directly to tape,
without making a print, is that the cinematographer no longer gets the
grading lights that gave them an accurate guide to both the density
and colour balance of the previous day’s work (see Chapter 8 for a full
description of grading lights).
Kodak were very aware of this and have produced a very nearly
ideal solution. They produced a very accurate and durable grey card
(see Figure 13.3), on each side of which is a white and a black patch.
Knowing that it is impossible to get pure white and black on paper
they set the very dark grey, masquerading as black, and the nearly
pure white paper, trying to be pure white, at very consistent densities.
They called this new card the ‘Grey Card Plus’.
The next step was to produce a clever box of electronics that would
recognize the signal associated with the image of this card and, if you