Originally Posted by hungro
I have read the instructions but are there more specific ones where 17 should be just "barely visible" 16 invisible. Barely visible meaning one click down and 17 disappears or it looks like 16 ie black or you go one click up and 17 becomes obvious and quite visible.
Commercial discs like Avia or Digital Video Essentials have their first levels above black around 19 or 20, and they suggest that those levels should be almost indistinguishably lighter than black. The PDF instructions for the second pattern are intend to follow that sort of thinking, basically trying to define "barely visible". Here is a relevant quote about the APL Clipping pattern:The 17 and 18 bars should not be clearly-noticeable, but you should be able to notice the bar marked 19 as it flashes. Turn black-level no lower than the setting where it is possible to see 19-28 flash. Try for just barely being able to see 19 flash in a typical viewing environment.
Originally Posted by PlasmaPZ80U
17 should be just visible against the background and 16 should be completely invisible. 18 should be obvious.
I know that the audio instructions from the HD Nation video support this position, but it's one of the few areas where I disagree with their comments. Display gamma would define the first few levels above black as being nearly indistinguishable from black, so ideally you would want your display to come out of black very gradually. Unfortunately some digital displays come out of black rather quickly and lack any sort of significant adjustment besides a brightness control. With a display that comes out of black too quickly you're usually left to choose between compromises like using a lot of light in the room or maybe clipping off a few levels above black. Generally 18 wouldn't be expected to be obvious when viewing an above-average display, with dim room lighting, from a typical distance.