Broadcast safe limiting

[Michael Gissing]

Oliver, I’ve delivered lots to broadcasters from Resolve and by setting output to Video levels, I’ve never had a tech reject for color gamut or luma levels outside broadcast safe. Resolve seems to do it without any other settings. Using Data levels you made need to set broadcast safe differently.

[Oliver Peters]

I always use video levels, but that’s not cutting it here. I’m dealing with previously graded material as a test. Turning on broadcast safe and setting the restriction to 0-100 seems to work. But then you still have to add some soft clipping to get the right look. The issue at hand is chroma slightly dipping below zero, not anything at the top end.

– Oliver

Oliver Peters – oliverpeters.com

[Marc Wielage]

There is a “Broadcast Safe” OFX plug-in available from BorisFX that claims to do it.

What I do is just use the Gamut Mapping towards the end of the node tree, set input/output to Rec709, and carefully tweak the levels as required. I find this often works better than a curve, particularly with hot chroma shots. I don’t use it throughout the whole show: I only activate it on the specific shots that need it.

The rest of the time, I might use a mild Soft Clip here and there or even use Log Highlights to pull whites out of being completely blown out. The rest of it boils down to keeping an eagle eye on the scopes and having a 6th sense for when we’re on the edge in terms of legality.

I’ve worked on about 150 films in the last 5 years for one specific client, and I think so far 3 have come back for fixes. One was for a level problem I missed, one was for a data glitch, and one was for a key that went south. So it’s rare we get caught on an illegal broadcast level. In truth, I think many broadcast channels are a little looser with what they will and won’t accept, but I treat levels like it’s still 1999 and try to err on the side of being conservative.

[Oliver Peters]

[Marc Wielage] “In truth, I think many broadcast channels are a little looser with what they will and won’t accept, but I treat levels like it’s still 1999 and try to err on the side of being conservative.”

Yep, good advice. The trouble is a general lack of consistency in whether they adhere to a default (looser) or a strict interpretation of levels standards. I find that some of the cable/streaming channels and channel groups appear to be more restrictive than the regular 3-letter broadcast networks. You’d think it would actually be the other way around.

– Oliver

Oliver Peters – oliverpeters.com