I've done a lot of research about calibration discs and have heard how wonderful they are, but what specifically do they allow you to do? On the video side of things, I keep hearing how they include "test patterns" to help dial in the picture, but what kind of test patterns specifically do they include and how do the test patterns help you adjust things? I'm new at this stuff, but when it comes to adjusting things on a TV there are some pretty basic adjustments; contrast, brightness, color, tone, etc. So it seems to me that with so few areas to adjust how can it be so hard to play around with these until things look good. I've heard some mention of service menus on various tv's that allow you to fine tune things even more, but I would have no clue how to get into this service menu. I guess I'm just skeptical by nature and always have my doubts about things until I'm shown otherwise. Maybe these discs are simply made to get your equipment back to reference standards... then I could maybe see the need for it. But people have different opinions on what looks or sounds good, and may prefer things different from the reference point. On the audio side, I know there are probably many more tweaks that can be made so I can justify the need for the disc. Each speaker has to be adjusted for volume, time delay, etc. using test tones, and the sub has to dialed in as well. What I'm curious about is what specifically these discs allow you to do. On that note, what disc would be best for me being a newcomer? I'm an engineer by profession so I'm pretty technical and don't necessarily need the one that's most user-friendly, but probably don't need the one that's the most in-depth because I am new to all of this. Thanks for the help.