2017

TIP As a reference, when setting softness and tolerance ranges, you can display the colour value for any pixel in
the key-in clip using the Plot tool. You can then adjust the tolerance or softness range so the pixel falls within one
of the ranges. For example, plot pixels at the edges of the matte to check for softness, or plot pixels in the
background to check for tolerance.
To plot a pixel's colour values:
1 Click Plot.
The cursor changes to a colour picker.
2 Select a pixel in the image area.
A red bar appears in each colour gradient showing the colour value of the pixel.
After you have adjusted the softness range,
set the tolerance range (page 700).
Setting the Tolerance Range
After you define the softness range in a colour model based component keyer, you can set the tolerance
range to remove the greys outside the key shape. The maximum and minimum tolerance values define the
range of colours to be keyed out in the key-in clip.
To set the tolerance range using the colour picker:
1 Click Tolerance.
The cursor changes to a colour picker.
2 Drag the colour picker around the area of the image that you want to key out.
The colour values that the colour picker samples are used to set the maximum and minimum values
for the tolerance range. The white lines define the limits of the tolerance range. All colour values
between the white lines are extracted from the key-in clip.
(a) Master Tolerance field (b) Minimum Tolerance field (c) Maximum Tolerance field
3 To increase or decrease the tolerance range, click the + or - button beside the Tolerance button.
NOTE An alternative method of setting the tolerance range is to press Command and draw a rectangle in
the area of the image you want to key out.
To set the tolerance range using the numeric fields:
1 Set the minimum value for the tolerance range using the Minimum Tolerance field on the left side of
the colour bar.
2 Set the maximum value for the tolerance range using the Maximum Tolerance field on the right side
of the colour bar.
NOTE You can also set the tolerance range by entering a numeric value in the Master Tolerance field.
700 | Chapter 16 Chroma Keying and Working with Green Screens