Hmmm, I wasn’t aware there was a difference. But no, I was testing on LED computer displays at Fry’s.
My sole intention in using an extra display was to have a screen for playback in FCP. Since I can’t, the new screen is occupied by my bin window, which de-clutters my laptop display quite nicely. So it still helps, but not in the way I had originally desired.
So what’s this blackmagic thing? Is that a type of screen or software?