| Properties | ||
 |
Key Color | The color to be keyed out. This color and similar colors will be made transparent based on the Threshold setting. Default: |
 |
Threshold | The amount by which the color of a pixel can differ from the Key Color and still be made transparent. Increase this to make a broader range of colors transparent. Note that the threshold is more sensitive to changes in hue and saturation (so you need higher thresholds to include more hues) and less sensitive to brightness, by a ratio of approximately 4:1. Range: 0 to 1; Default: 0.1 |
|
Feather | The softness of the transition between transparent and visible pixels over the given threshold. Near zero, transparent areas have a hard edge. As this value increases, colors close to the Threshold will become partially transparent. This can result in a smoother edge, but can also result in more of the background or key color showing through, creatig a colored fringe around the layer. Use this together with Defringe for best results. Range: 0.01 to 0.75; Default: 0.05 |
 |
Defringe | Enabling this causes Chroma Key to attempt to remove leftover tints in the Key Color from partially transparent pixels along the edge of the key. Default: off |
|
Invert | Turn this on to reverse the effect and keep only the key color, while removing other colors Default: off |
Usage
Apply Chroma Key to any video or image layer, and set Key Color to the color that you want to make transparent (this is best done using the Eyedropper tool). Adjust the Threshold first, then fine tune Feather until the edge looks the way you want. If working with a subject with a soft or fuzzy edge (this can include hair) it is often helpful to turn on Defringe.
Setting Up Your Capture Environment
When recording video to use with the Chroma Key effect, setting up your stage and lighting correctly can significantly improve the results.
For the background (the parts of the video you want to remove), make sure you have a solid, vibrantly colored wall, cloth, or pop-up screen covering the entire space, and try to light it as uniformly as possible. Changes in color due to shadow will be more difficult to remove in editing. If using a cloth, try to avoid wrinkles. The best color for the background is generally a solid bright green, blue, or orange.
Try to keep foreground objects (people or other things you don't want to remove) as far in front of the background as possible to reduce fringing from light reflected off the background. Also make sure that foreground subjects don't include any colors that appear in the background, otherwise they will be removed as well, resulting in "holes" (this is why a white background is not good: If the foreground subject is a person, the whites of their eyes will also be removed.
Use Cases
- Replace the background in video recorded in front of a green screen.
- Isolate a solid-color object from a non-solid background for use as a mask (turn on Invert for this)
- Isolate part of a video or photo to apply color correction only to that area (for example, to make only greens more vibrant by isolating them with Chroma Key and then adjusting with the Saturation / Vibrance effect). For this use case, either duplicate the original layer, or create a rectangular shape on top of the original image and apply the Copy Background effect first before applying Chroma Key.