As a chemist, I'm accustomed to thinking of electrons in the wave/particle dualistic sense and their energy orbitals in terms of quantum mechanical wave equations and probabilities. But I would like some input on the following thought experiment relating to photons and the wave behavior of light. If we place a light source in the center of a room and flick it on briefly, all walls, floor and ceiling are illuminated. Jillions of photons. But what if our light source were designed to allow only a single photon of energy to be released? My thinking is that, given that the energy released is a quantum mechanical wave, that wave propagates from the source at the speed of light in all possible 3-D directions. Theoretically, illumination can occur anywhere in the room where an object might be struck by that photon. However, the very first "contact" with an object causes the wave equations to collapse and the photon at that instant exhibits particle behavior, and that one miniscule spot, no matter where we decided to put the object, is the only spot illuminated, and because of our random choice of location for the object, that becomes, de facto, the "direction" of the wave/photon from the source. Is this an appropriate understanding of light's wave behavior?