I want to overlay two videos. One video has some light and primarily a black background. I do not want this black background to show up in any way when I lower the opacity of the video.
Thanks in advance
Play with the layer Blend Modes
As suggested, you can blend two layers together by setting the blending mode of the upper one to something other than Normal.
See this page for an overview of all of the ways that you can superimpose one layer over another. The general term for this is 'compositing'.
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