Luma Key (or Color Key or Ultra Key) not working on adjustment layers. Bug or limitation?
Hi
I just noticed a big issue in Premiere Pro and I'm not sure if this is a bug or a nasty limitation (or maybe I'm doing something wrong). I tried to use an adjustment layer (over a couple of clips) that contains some effects and I wanted to use a Luma Key on this adjustment layer so the darker tones would become transparent, but it doesn't work. Here's an example: let's say I have this clip underneath the adjustment layer:

and on the adjustment layer I use a Mosaic effect and a Lumetri Color so I get this:

All good so far. Now I add a Luma key on this adjustment layer and I set the threshold to around 50% and I expect to get something like this:

(this is made in Photoshop to ilustrate what I was expecting to get in Premiere)
But unfortunately what I get instead is this:

So the darker tones of the adjustment layer are not becoming transparent, they just get more darker.
Any thoughts?
