Hi i notice that you mention that a few playstation 2's may require this but can i ask what do you mean exactly by calibration and alignment of the laser eye. i presume alingment is to do with the white cog and stuff but whats the calibration and how do you do it?

usually means by recentering the lens back into its idle sitting position... after a while the lens may move off center from taht position and has to be pulled back to dead center also the laser may have to be adjusted to that point awell...

it all depends on the condition of the laser itself

also calibration is also noted when you adjust the voltage to the laser to how bright it fires.. to bright or to dim the pickup won't see anything.. to the naked eye its hard to see it any difference but to a laser cd eye its night and day.. hopefully if people do try this they do not to stare to long or directly into the laser itself

a pickup laser has to be at a precise intensety to operate properly
IE the 2 POTS ( Varitable Resistor )

and one of the methods is to turn the white adjustment gear at the back of the drive