A screen shoot give always only very bad resolution !

Peter,

that's not generally valid! It depends on what you want to do. If you want to publish a circuit consisting of some transistors, resistors, etc. a screen dump is fully adequate. Even if you publish PCB with simple microcontroller circuit (DIL package), some buttons, some LEDs and a crystal, ordinairy screen dumb will suffice.
But if you want to publish a large area PCB with many SMD parts, then of course simple screen dump will not satisfy...

Kai