iTT captions appear too dark on Rec. 2020 HLG clip
I'm working on FCPX 10.6.1 with MBP 14" 2021, and editing clips from iPhone 12 Pro. Because they are in HDR, I changed the clip format to Rec. 2020 HLG. I added additional images and titles, and because they appeared too dark I used HDR Tools effect, changed the mode to "PQ to HLG (Rec. 2100)", and reduced Peak Brightness (nits) to 100.
The colors turned out nice, but the only issue I have now is with the iTT captions, which actually appear alright on FCPX (the white is still not very bright white), but when I export the final project clip they appear too dark (dark grey on a black background bar).
I tried to take a screenshot, but the clip's colors are entirely off, and the color of the subtitles is good. This HDR is so tricky and frustrating...
When I export the clip the colors are good and the color of the subtitles is grey as I mentioned before.
Is there any way to correct the color of the subtitles? By the way, I would also like to remove the black bar background and outline the letters if possible.
MacBook Pro 14″, macOS 12.1