Thanks for the posts. I probably sacrificed too much clarity for the sake of keeping the original post brief, nevertheless I think my question has been answered one way or another.
My original experiment as I envisaged has two detection mechanisms. The first is a photosensitive plate, maybe...
I'm wondering if someone could tell me what would be the result of the following thought experiment, to help answer a simple question I have about the Heisenberg Uncertainty Principle:
(I am just an educated layman trying to figure it all out- hopefully my thought experiment isn't complete...