When
you balance the colours in a clip, you should always start with
the darkest and lightest parts of the image. You may, for example,
need to establish parameters for the black and white (luma) content
to ensure that the intensity of the image is in accordance with
established broadcast parameters. These parameters are known as black
points and white points. You use the Black
and White fields to establish black and white points.
Black
fieldModifies the luma in the image's shadows without
affecting the chroma.
White
fieldModifies the luma in the image's highlights without
affecting the chroma.
To set black and white levels:
- Sample the highlights in the image. To
determine the white point, select a white that appears to be flat
rather than reflective so that you obtain a more accurate reading.
Do not use a highly reflective surface such as a window or metal
surface as they are often too bright. Enable Plot and then sample
the whites in the result clip.
In the Basics menu, a
red plot line is displayed in the 2D luma histogram indicating the
luma value of the sampled whites in the result clip.
- While viewing the 2D luma histogram and
the image, adjust the white level to modify the luma value and set
the white point—drag left to darken the highlights and
right to lighten them. The Plot sample is updated as you drag the
field.
TipYou can view both
the 2D luma histogram and 2D vectorscope to determine what adjustments
you need to make to the highlights. For example, if the white point
is set to an acceptable level in the 2D luma histogram but the sampled
chroma value shows an unwanted colour cast in the 2D vectorscope,
use the Highlights trackball to modify the chroma value in the highlights.
See
Removing Unwanted Colour.
- Enable Plot and sample the shadows in
the result clip to determine the black level. Sample the darkest
part of the image to determine the black point.
A red plot line is displayed
in the 2D luma histogram indicating the luma value of the sampled
blacks in the result clip.
- While viewing the 2D luma histogram and
the image, adjust the black level to modify the luma value—drag
left to darken the shadows and right to lighten them. The Plot sample
is updated as you drag the field.
TipOnce the black level
is set, you can use the Shadows trackball to adjust the chroma values
in the highlights while viewing the plot sample in the 2D vectorscope.
See
Removing Unwanted Colour.