I will relate to you what I was once told. Hopefully it's somewhat accurate.
Firstly, I haven't even seen these particular grades before, but I'm assuming it's the same principle as the DV only (no "H") grades of panasonic tapes.
So, they have DVC, PQ, and MQ (now AMQ) grades. One is the lowest, one the middle, one the highest, and their prices reflect such.
What makes the grades different?
Apparently the tape itself, the the black stringy stuff that records your video, is cut from some huge roll. Like a roll of toilet paper, or something vaguely similar. So, the outer edges of the roll are more exposed to the elements/contamination, whereas the center is somehow or other enclosed and protected from dirt and filth.
So the lowest grade of tape comes from the outer edge, mid grade comes from between edge and center, and high grade comes from center. So, Seriously. . .this is what I heard. Is it right? I think there's a kernel of truth buried in there somewhere. What it boils down to is that, within a certain brand, the more expensive the tape, the less prone to dropouts and errors it should be.
Edited by Josh Bass, 08 November 2008 - 04:27 AM.