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RGB Difference Key effect

The RGB Difference Key effect is a simpler version of the Chroma Key effect. It lets you select a range for the target color, but you cannot blend the image or adjust transparency in grays. Use the RGB Difference Key effect for a scene that is brightly lit and contains no shadows, or for rough cuts that don’t require fine adjustments.

For more information, see Difference Matte effect.

Note: The Difference Matte effect uses a matte to define the alpha channel much as the RGB Difference Key effect uses a color.

The following RGB Difference Key effect settings are adjusted in the Effect Controls panel:

Color
Specifies the color in the video that will be made transparent by the mask.

Similarity
Broadens or reduces the range of the target color that will be made transparent. Higher values increase the range.

Smoothing
Specifies the amount of anti-aliasing (softening) that Adobe Premiere Pro applies to the boundary between transparent and opaque regions. Choose None to produce sharp edges, with no anti-aliasing. This option is useful when you want to preserve sharp lines, such as those in titles. Choose Low or High to produce different amounts of smoothing.

Mask Only
Displays only the clip’s alpha channel. Black represents transparent areas, white represents opaque areas, and gray represents partially transparent areas.

Drop Shadow
Adds a 50% gray, 50% opaque shadow offset 4 pixels down and to the right from the opaque areas of the original clip image. This option works best with simple graphics such as titles.