Re: "wouldn't the charges involved modify the trajectory"
I have this miraculous device called a 'mirror' that seems to do the job pretty well...Trajectory: "The path of any body moving under the action of given forces; by many modern writers restricted to that of a body not known to be moving, like a planet, in a closed curve or orbit; esp. the curve described by a projectile in its flight through the air."
If you have any evidence that the path of photons from your "miraculous" mirror are travelling in curves, please present it. You could be in for a Nobel prize!