Hi, I have a little question about the double-slit experiment, if this is the right place here, the right category? When the particles/waves are hitting the wall (the screen): Is that a mesurement as well? I would say Yes, it is, but would like to here a confirmation or a correction. And --sorry, actually a two part question-- if so, have there been experiments with a semi transparent wall as well with a second wall just behind? And if so, what did the second picture looks like? Sorry for my poor English. I did not read every thread before, so maybe this is a double question.