Because of time dilation, light emitted (or reflected off of) objects very near the event horizon end up getting spaced out over (almost infinite) amounts of ti

Because of time dilation, light emitted (or reflected off of) objects very near the event horizon end up getting spaced out over (almost infinite) amounts of time. For example, lets say you dropped a beacon that flashes every second into a black hole. As it approached the event horizon, you'd see the flashes only happen every 2 seconds, 4 seconds, minute, hour, decade, etc. Meanwhile, the length of those flashes are getting longer at the same rate, while producing the same number of photons, so the light gets dimmer and dimmer.