While working on another effect I wanted some simple luma key controls, but no Motion effect had the parameters I wanted to publish, so here's my subset of the Luma Key controls.



You choose which areas of the clip to include based on brightness:



In this case the value for Upper Limit has been reduced so that the brightest parts of the image are now transparent.

If you increase the value for Lower Limit, the darker parts of the image become transparent:



For a little more information and download link, visit my blog.

Well this certainly opens up many new creative possibilities!
Once again, Alex, thank you for the sterling description & excellent share.

This is Awesome Alex! Been using your mattes for 6-7 years, if not longer, love your stuff!