Handbrake woes

[Dr.Ling]

Ok, old thread, I know, but this handbrake adjustment thingy is important! (and please refrain from replying that "we don't need a handbrake to go sideways, just kick the clutch, or install a SR20DET")

I did this adjustment but I think I screwed up, no improvement. Might of course be my handbrake-cables that have rusted, or stretched too much, but pulling the handbrake makes the handbrake-levers on the calipers move, so I think cables and levers are ok. Maybe a piston overhaul is due, cause it was a bitch to turn (though I probably should have at least taken the cap of the brakefluid reservoir, or opened the bleeding nipple on the caliper a bit).

I probably need to know more about how the rear caliper pistons work, because I don't get how (after turning the piston "in" / clockwise, and out again) applying pressure on the piston + pumping the brakepedal will make the piston adjust itself outwards (closer to the inside pad). I thought it adjusts itself further out when it senses less pressure (when pads or discs wear thinner).

And by the way, does the handbrake-lever on the caliper push the piston hydraulicly or mechanically?
I assume the screw inside the piston, which makes itself longer after pad/discwear is the "adjuster", and it's this that makes both footbrake and handbrake work when discs/pads get thinner?

As a supernoob I tend to ramble on, sorry