User Manual

The default qualification mode is the HSL Qualifier, which uses three color components, hue,
saturation, and luma, to define a key. However, you can also use the RGB or LUM (Luma)
qualification modes to pull keys using other combinations of color components. The LUM
qualifier mode, in particular, lets you make targeted adjustments to specific ranges of image
lightness. This is a technique employed by many colorists to alter color temperature within a
specific range of image highlights or shadows.
Alternately, you can use the 3D qualifier to quickly and easily pull well-refined keys by drawing
lines to sample colors from the image that correspond to volumes of color within a
three-dimensional gamut. While the underlying technology is sophisticated, all you have to do
is to draw blue lines to sample colors you want to isolate, or red lines to sample colors you want
to subtract from the isolation you’re creating, all of which automatically generate a
high-quality key. Each line you draw adds a sample to the selection list; you can turn each
sample off and on to evaluate its contribution to the resulting key, or delete samples that don’t
make a positive contribution.
The 3D qualifier
No matter which qualifier mode you use, the Matte Finesse controls make it easy to refine the
resulting key to be even cleaner and more usable. In some instances, you can even take a
marginal key that would otherwise be unusable, and squeeze it into something useful using the
Clean Black, Clean White, and Blur Radius controls.
Which Qualifier Do I Use?
The Qualifier palette’s four modes offer you the flexibility to use the best keyer for the job when
it comes to isolating a range of color or brightness values. In some cases, keys that are difficult
to pull using some modes are easier to pull using others. Here’s a brief summary:
 3D: The 3D keyer is a good one to start with if you’re trying to isolate a range of color
such as a blue shirt, a cyan sky, a performer’s skin tone, or the orange leaves of a tree
in autumn. Its interface of drawing lines over the part of the image you want to isolate,
coupled with its high quality and extreme specificity, make it a fast and accurate tool
to use in a variety of circumstances. However, the 3D keyer always samples every
color component of the image; it’s not useful when you want to isolate specific color
components, such as luma only, or hue and saturation without luma. The 3D keyer’s
greatest strength, the speed with which you can sample areas of the picture to include
(or exclude) from the final key, is also occasionally a weakness with images where your
initial samples aren’t giving you satisfactory results, because there aren’t many ways to
fine tune the key as it’s being generated (although you can manipulate the result). On
the other hand, for most images you would want to qualify, two or three samples is all
you need, in conjunction with using the Matte Finesse controls to adjust the resulting
key. If you need to do some compositing in the Color page, the 3D keyer also does an
excellent job doing blue and green screen keying to create transparency, and has a
built-in Despill control as well.
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