Just tried to calibrate the tv using the Spears and Munsil disk. I am unable to display the pluge low pattern no matter what I do. I tried ajusting the brightness to 100 and the contrast to 0 but there was no change - no test patterns shows up. I tried studio ref mode, custom, vivid and standard to no avail. In general, the tv does not seem to respond to brightness adjustment. What am I doing wrong?

The black background doesn't even light up with brightness at 100 (and leaving the contrast at default)?
If it doesn't, your brightness control doesn't seem to be working right, which is very odd.
If the background does get lighter but you just don't see the pluge bars (1-4% bars) then your DVD player is probably crushing black. That could be a problem with the player, it's controls, or anything else in the signal path like a receiver or switcher.

Thanks. I figured out the problem. The room was too bright and I was sitting too far away from the tv to see the bars.