Primary Color Correction: Tonal Range Primer - The Art and Technique of Digital Color Correction - page 18

do not crush the detail out of one channel that may be lower than the
other two.

D e f i n i t i o n
Low Pass: A mode or set-
ting on the waveform mon-
itor that filters out all of
the chroma information in
the image as it displays the
waveform, allowing you to
analyze only the luminance
values. The opposite of this
setting is Flat, which does
not filter out the chroma
information. On some
scopes, especially those
internal to many desktop
applications, the Flat mode
is called Y/C, which stands
for luma/chroma. This Y/C
mode is often displayed
with the luma and chroma
information in different
colors. On a standard
waveform monitor in Flat
mode, the luminance and
chrominance values are
indistinguishable by color
on the display.

Reading the Waveform Monitor

Let's take a look at an image and determine the proper black level looking
at both a standard waveform image in Low Pass—or luminance-only—

Fig. 1.19 (a) High-defi-
nition still from Artbeats'
Sports 1 HD collection—
SP120. (b) Waveform image
grabbed from a Tektronix
WVR7100. (c) Artbeats'
image from Sports 1 HD
collection overlaid with
waveform display.