This determines the brightness level that becomes transparent. Increasing this value targets and removes darker areas first.
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If smoke is light gray, raising the threshold might erase it. Solution: Duplicate the smoke layer on Track 3. Luma key both layers. Overlap them to increase density. luma key premiere pro free download
Would you like a step-by-step tutorial on using the Luma Key effect in any of these programs? luma key premiere pro free download
Once applied, navigate to the panel to fine-tune the transparency: