Chroma key similarity settings in VSX7

[Ken Veal]

Chroma key similarity settings in VSX7
When you move the colour similarity slider, what does it actually do.
Further, I am wondering if using changes to it in a clip could bring up some effects that I have not explored yet .Has any one toyed with this and what sort of effects could be achieved ?
Ken

[aljimenez]

Try it yourself; it won't hurt anything. As the slider moves, the color purity desired changes. At one end, all of the image becomes transparent, and at the other end only the pixels that are pretty close to the same are transparent.