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Broadcaster unsure of which RGB standard it uses – your recommendation?
It’s rendering time for the TV series I’ve been working on.
I’ve reviewed the standards I was provided one more time … and realized there was something I was still unclear on.
The broadcaster wants 0-100 IRE. I asked, well, that’s great for analog video, but is your digital standard RGB 0-255 or 16-235.
Answer from Master Control:
“On a digital waveform it should be 0-100 and on an analog it should be 7.5-100. I’m not sure how that translates to the RGB color model as I don’t have much experience with it but if you go with the Waveform we should be safe. I’ve got a feeling you shouldn’t have to worry about it too much unless your original footage was way off.”
Hmm.
Okay, I’ve done the whole series with an eye to 0-100 on the scopes, but in 0-255 space. That is, I’m pretty sure I did NOT have the scopes set to Studio RGB.
What do you recommend now that I’m rendering the masters?
– John Rofrano says in this thread https://forums.creativecow.net/thread/24/939445 that the Broadcast Colors filter CLIPS instead of adjusting the levels. IIRC, that was true in early versions of Vegas, but is it still? John, your advice at the time was to use Levels, then Broadcast Colors as a last line of defense. Still your recommendation?
– Should apply a Computer RGB->Studio RGB levels on the master, then the Broadcast Colors to make sure my colors are safe? Or just use Broadcast Colors with the Studio RGB checked?– OR… Should I just leave it at 0-255 and let it fly? I’m starting to think Studio RGB is the best bet if I’m blind to what they’re expecting on the other end.
And, if it’s relevant, I’m rendering to MXF (Mpeg2 in the MXF wrapper, 35kbps).
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Radio guy in a TV world. Bigasssuperstar.com -
6 Replies
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[Scott Simpson] “- OR… Should I just leave it at 0-255 and let it fly? I’m starting to think Studio RGB is the best bet if I’m blind to what they’re expecting on the other end.”
You are talking about something completely different than the station engineer. This has nothing to do with color. He is explaining that your Lumanance levels need to be between 0 – 100 on the Waveform monitor. That’s it. Open the Video Scopes, go to the Waveform Monitor, and make sure that your levels never exceed 0 -100. Use the Sony Levels filter to bring then in-line if they are out.
~jr
http://www.johnrofrano.com
http://www.vasst.com -
John, I’ve done that. I’ve used the waveform monitor at every step to keep my levels between 0 and 100.
What I did not do is change the waveform monitor to make 0=16 and 100=235. I’ve been working in 0-255 space.
Thus, my whites are 255 and my blacks are 0. If the broadcaster is expecting 16-235 instead, my blacks while crush and whites will be blown out.
As you know, the Broadcast Colors filter (which I will use to catch any illegal colors that made it into the project) also lets me catch any illegal luma values. You’ve said before that it does so by clipping, as opposed to adjusting them like Levels does.
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Radio guy in a TV world. Bigasssuperstar.com -
I would adjust the whole program level by applying the ‘Sony Curves’ plugin at your program Video Output FX plug point and then adjust your average white levels down to 100 IRE and your blacks up to 0 IRE.
Then as an overall rider just in case you have any quick transient peaks that want to shoot over 100 IRE I would apply the Sony Broadcast Colors plugin at the same point and select ‘conservative’ for the setting. Camera flash guns are classic examples of rapid overshoot levels.
Make sure your waveform monitor selection is set to 16-235. All material for broadcast should be created using these levels.
While at it I would check with the broadcaster about what audio levels you should deliver. Most do not want audio peaks to go over -10db. Do all of the above and hopefully you will meet their specs.
Chris Young
CYV Productions
Sydney -
[Scott Simpson] “What I did not do is change the waveform monitor to make 0=16 and 100=235. I’ve been working in 0-255 space.”
Then you must have changed it because the default is 16-235. It’s also important to understand that the Waveform Monitor does not measure color, it only measures Luminance. You should be using the Vectorscope to measure color. This will tell you if your colors are within the legal limits which are identified by the boxes on the scope.
[Scott Simpson] “Thus, my whites are 255 and my blacks are 0. If the broadcaster is expecting 16-235 instead, my blacks while crush and whites will be blown out.”
Just make sure that your colors are with the proper ranges on the Vectorscope. If you have whites and blacks from titles or other generated media, then you need to go back and adjust them to be broadcast compliant. Even if you do that, you should still place the Broadcast Colors filter on the Master Video Bus with the Conservative preset and let it restrict any colors you may have missed. Yes, it will clip which is why you should adjust these yourself but if you check your colors with the Vectorscope you should be able to fix most of them yourself.
~jr
http://www.johnrofrano.com
http://www.vasst.com -
Yes, that’ll be my workflow moving forward. When I was doing videos primarily for YouTube and the like, the tutorials seemed to universally tell me to set the scopes for 0-255 so what showed in the preview window was “real”, then apply the computer -> studio RGB filter at render time if the destination desired it, which YouTube does.
That was all fine and good for short videos. Now that I’m trying to render a TV series, setting all my levels to a scope where 0 is black and 255 is white is coming back to bite me in the behind.
Going forward, I’ll be living and dying by the waveform at 16-235 unless I’m specifically instructed to it differently.
Colors, I get it — when I went about adding saturation etc., I watched the vectorscope to be sure everything was legal. The Broadcast Colors plugin is just to catch anything that ended up out of range outside of my scrutiny.
The main question I was trying to ask: If the broadcaster doesn’t know if it’s using RGB 0-255 or RGB 16-235, which is the best one to choose; and if 16-235, what do you recommend to push projects that are already completed at 0-255 into that range?
In lieu of a clear answer, I’ve put a Levels plugin (Computer RGB->Studio RGB) on the master, with the Broadcast Colors plugin after the fact to catch any strays.
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Radio guy in a TV world. Bigasssuperstar.com -
[Scott Simpson] “In lieu of a clear answer, I’ve put a Levels plugin (Computer RGB->Studio RGB) on the master, with the Broadcast Colors plugin after the fact to catch any strays.”
That’s is a good plan. Broadcast TV is always Studio RGB 16-235.
~jr
http://www.johnrofrano.com
http://www.vasst.com
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