Ok, thanks. Does that mean that a large percentage of the photon emissions don't strike the recording apparatus at all, having struck the barrier instead of passing through a slit?
I'm just a layman with an interest in science, so my terminology won't be accurate. Sorry.
Set up for question: the wave-front splits as it passes through the slits and must (I guess?) condense to a point upon impact with the recording device (paper/film etc).
The question: if a photon is...