Mon Dec 27, 2021 12:53 pm
Hey Mike,
I realized that for me, what happened was that the key input's "matte/mask" button was keyframed for some reason, though it was very unclear as to what the issue was, let alone why it happened. I don't remember pressing it, but I'm pretty sure I used the automatic keyframing mode to make my changes, so maybe it was a bug having to do with changing parameters on the same page? I only found it through what should have been an unnecessary amount of scrutiny, but I think it's ambiguously grouped in the "Color correct..." keyframe track. (I'm assuming that's just "color corrector", but even though I have plenty of screen space I can't widen the track names column at all apparently.)
Essentially what was happening was my key was inverted until the second keyframe, so my smooth changes technically happened correctly, just only to the parts of the image I didn't care about, and then it switched on the last frame to the affecting the part I was trying to use the power window on.
Long story short, if you're running into the same thing, check to see if that button get switched on the single keyframe where all the changes appear to be happening at once, and if so, enable auto keyframing, put the play cursor on the other keyframe and toggle it to match. I'm kind of curious to see if this is the same issue you're seeing, so if you feel like it, let me know if this works for you when you get a chance to try it.