I remember reading on an old Sony Wega calibration site that changing the sub focus can yield better resolution. It has a different abbreviation on the XBR800, but it's there. I remember the site saying that you have to use an Avia or VE test pattern to get the best results. There are only 4 settings (they are 0,1,2, and 3). The guy on the site said he changed his, and he doesn't remember to what setting, but he knows it wasn't the factory setting (1).