How to calibrate a CRT's contrast (picture) using AVIA is quite confusing to me. OK, the instructions say stay below the points of blooming and high voltage capacity. Both of these cannot be reached on my CRT even when the contrast is turned all the way up so do I turn contrast all the way up to get the best results? All it says is keep raising your contrast until the gray background ceases to be gray and becomes white. Is that pure white or just a little white or what. Is the highest possible (without damaging the CRT) contrast better/preferable? I'm just confused. Thanks.