Originally Posted by tbrunet
Since theres no digital video formats in the consumer domain that contain or encode (7.5%) setup, the digital "%" level and the IRE value will be the same.
Avia labels black 7.5 IRE, not 0 IRE. Depending on how the end-user uses a calibration disk, black could be said to be output at either 7.5 IRE or 0 IRE. That does not match what you said, so how is that not generally confusing?
Strictly speaking the information is actually YCbCr, but for simple understanding no one labels things that way. Of course everything I've brought up so far can be altogether avoided if black is defined as 0% and white as 100%. The latter percentages are simply far simpler to communicate to an end-user than getting into either what IRE or YCbCr mean. This is the same point I was making with Doug's attemps at a more complex definition of clipping, for the purpose of this forum it's simply not necessarily important to have all that information and a simple definition works for the task at hand.
If you would have understood the profound intention of that quote
You're so full of it, but I think you're amusing none-the-less. Like I said the information is YCbCr and understanding IRE brings nothing to the table for a general end-user calibration. As you've said in some contexts 0 IRE matches 0%, but when it comes to outputting from a player 0% is less ambiguous because black can vary when using the IRE term. So with percentage you have a defined level if you know the source, but with IRE you have to know how things are output which introduces uncertainty. Like I've offered before, if I'm dead wrong then by all means please enlighten me as to how IRE is so "profound".