Right. I've gone as far as I can go using my eyes and AVIA / DVE and i'm ready to go the next step. I would like to calibrate my modded BenQ PB6100 and find out it's actual contrast ratio, lumen output and also determine how accurately it's tracking colour from 0 ire - 100 ire. At the end of the exercise I want to have a perfectly calibrated projector even if filters are required and max out it's contrast ratio. So. What do I need and what are the techniques. I suppose I should start with a light meter. What spec etc will do?