Specifications

ptg
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Performing Automatic Color Corrections
Manual Color Balance Controls
When you alter the color balance of an image, you are actually adjusting
the levels of red, green, and blue that are added to parts of the video sig-
nal (shadows, midtones, and highlights).
The ChromaWheels in the Color Correction tool allow you to offset the
chroma values in each of three luma ranges. For example, if the high-
lights exhibit too much blue (which you can measure using the RGB
Parade monitor), then you could drag the center crosshair on the highlight
ChromaWheel away from blue, toward the complementary color of yellow.
(As usual, the automatic color balance controls can do this for you, but you
may need to tweak some values.)
Performing Automatic Color Corrections
When you apply auto adjustments in the HSL group, you should first
adjust the black and white levels using Auto Contrast and then correct
color casts using Auto Balance. Then, if necessary, you can refine these
values using the manual controls.
To make an automatic contrast adjustment on the H S L tab:
1. Move the position indicator to the segment you want to correct and to
a frame that has many of the shot’s visual characteristics.
2. Make sure Hue Offsets > HSL tab is selected.
3. Display the Y Waveform monitor in the left color correction monitor by
selecting it from the menu. You should see the “current” frame in the
middle monitor and the Y Waveform in the left monitor.
4. Click the Auto Contrast button
.
Auto Contrast adjusts black and white levels and maps the darkest part
of the image to video black and the lightest part of the image to video
NOTE As you make your
first adjustment within
the Color Correction
tool, notice that a color
correction icon appears
within the segment being
corrected.
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