laser adjustment
 

i have a v.5 ps2 with messiah2pro.it boot perfectly but made scracthes on the dvd HK pressed(gold) backups.i heard about azimuth and i tried to made it.i adjusted the laser.it boots dvd HK(gold)backups perfectly but this time it makes scracthes on silver colored dvd backups.it seems that i cant find the right angle.
while udjusting i turned the screw clockwise(halfturn) until it doesnt boot.the counterclockwise until noboot.between this two points it boots everytime.but it makes noise like sometheing touches dvd.how can i find the right angle?