Removing super blacks in split screen shots?

Robert W wrote on 10/22/2008, 4:48 PM

I've giot a vide owhic hhas a lot of split screen shots, a bit like to ones all over "24". i was wondering ,what is the correct way to handle what i guess are super superblacks that occur in the gaps between the shots? It only occured to me today that these blacks are not picked up by the broadcast filter as they are not actually part of the event or track image, and would therefore still register at a very low level.

I was thinking about adding a sony solid colour at RGB 16/16/16 on the lowest track to handle this. Would that be the right step? And how much harm could those blacks do?

Comments

GlennChan wrote on 10/22/2008, 4:50 PM

Adding a solid color generator on the bottom track, like you said, would be a reasonable way of doing this.

Apparently on older sets, superblacks can cause the picture to roll and be unwatchable. I haven't come across such a set myself though.

Robert W wrote on 10/22/2008, 5:35 PM

Thanks Glenn, I very much appreciate your expertise on all things technical and colourful :)

I only really addressed this as an issue because Neat Video was getting confused with the super blacks in the first frame of a split screen shot. it was thinking that the preceeding full screen shot had noise in all the areas where the the split screen had no signal. So effectlively the last frame before the cut to the split screen was getting masked out as if it was the split screen shot.

I am probably far to tired to make any sense here. But in short, watch the super blacks with the Neat Video plugin.

rmack350 wrote on 10/22/2008, 9:34 PM

my own CRT TV pumps when you go from superblack to a fairly bright shot. Adding a base track of 16/16/16 black solved that.

farss wrote on 10/22/2008, 11:30 PM

My Sony broadcasty monitor does the same.

Now here's a piece of trivia. Friend of mine bought three BVW 75s at auction for $50 each and one of them has a sticker on it that says it's been modified for superblacks, why was that done to some SP decks?

I don't know the answer, all I can guess is they might have used superblack for keying supers seeing as how none of the analogue gear supported an alpha channel.

Now that I think about it that's a pretty clever idea. DV tape supports superblack out of the box, easy enough to key on that, hmmm.

Bob.

rs170a wrote on 10/23/2008, 4:09 AM

...they might have used superblack for keying supers...

Give the man a gold star :-)
Back in the late 70s/early 80s, I would crush blacks on a video camera when I shot title cards (this was long before electronic titlers) so that I could get a better key.
This same thinking was eventually carried forward to decks like the BVW 75.

Mike