Spears & munsil, and DVE both specifically instruct the user to adjust the brightness to allow the 2% above black bar to disapear into the background, which is video black, and then adjust the brightness up 1 or 2 clicks until it JUST appears again. (on the DVE disc, this is the pluge pattern with grayscale ramps, and on S&M this is the 4 bar pluge, 4% below, 2% below, 2% above, 4% above)
Quote from S&M disc: "Lower the brightness control until the faintest right bar disappears, then raise it a notch or two until both right bars are visible. When everything is set right, the far-right bar should be clearly visible, and the darker bar should be just barely visible above the background level."
This is very different then how we are instructed to adjust the black level with the AVS HD 709 disc, which has us adjust brightness until bar "17" is flashing. This makes the 2% above black bars on the DVE and S&M discs extremely visible and bright. The difference between the two ways of doing brightness makes a large impact on the picture.
So are there any explanations on this?
I experimented with lots of different content, mainly blu ray movies, television, and some video games, and found no real increase in shadow detail between the two ways of setting up brightness. One setting was just deeper and richer, and the other setting was brighter and slightly more washed. I saw no gain in detail adjusting with the AVS HD 709 disc.