16-235 vs 0-255?
OK..I’m revisiting my continued battle with broadcast legal colours and translation to Adobe, or more broadly the digital domain.
I asked on various forums a little while ago if anyone could offer up a definitive answer to what exactly are broadcast legal colours for PAL transmission in the UK. Clearly it is WAAAYY more complex a question/answer than just that and I’ve learnt an awful lot..
However, I’m still not 100% clear on the Broadcast Colours effects in Premiere and AE. Basically we have used mainly Quantel kit or hardware based linear suites in the past which are totally capable of creating levels beyond 255. Now Photoshop et al cannot, to my knowledge, create or process anything outside the 0-255 range. This is an RGB range right? Well it seems from doing alot of reading that in the UK at least, PAL broadcast standards specify your ranges must be within 0-255, *NOT* 16-235 as has been suggested in various places..which puts my mind at ease somewhat and stops a bit of head scratching (I’d done various tests on TVCs that we had sent for broadcast and we’re deemded ‘fine’, but when tested within AE they were showing up 0-255, depsite the b/cols effect putting PAL between 16-235)
SO….I’m wondering whether infact this 16-235 range is specifying YUV values and not RGB? I tested this on the Paintbox within our Editbox which can operate in either colourspace…In the palette my white was reading 255 in RGB values, but 235 in YUV. If this is the case then surely you don’t have to worry about creating illegal colours from within Adobe products…right?
Or have I got it all screwy?!?
An garbled post to be sure, but if anyone fancies wading in to explain all this I’d be really greatful!
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