I rewatched BOBW Part II yesterday. In the scene where Picard's face was turned white, it was originally accomplished by making the shot B&W, and adding in the red laser.
I see with the HD remaster, they don't remove the color from the shot. You can still see the color of the set. Picard's face is digitally turned white instead. Much better.
Nah, that's not true. You can clearly see the color still in the probe, the background, and on part of Locutus' costume. Of course, the whole thing is already muted far beyond the quality shown on the Blu-ray, but stilll...