My understanding of parabolic reflectors is that a point light emitter at the focus point should have all its rays reflected out straight & parallel. Maximum throw, tightest possible hotspot. All the rays that leave the light without hitting the reflector make up the spill. But since all the rays from the reflector are parallel there would be a hole in the middle of the hotspot. Now in practice this is going to be a little less pronounced since the emitter is not a point but an area, so not everything could possibly be parallel and things will be a little smudged. But still. A perfectly focused LED should have a donut hole in the beam. So basically it’s a sign of good focus and actually desirable?
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My understanding of parabolic reflectors is that a point light emitter at the focus point should have all its rays reflected out straight & parallel. Maximum throw, tightest possible hotspot. All the rays that leave the light without hitting the reflector make up the spill. But since all the rays from the reflector are parallel there would be a hole in the middle of the hotspot. Now in practice this is going to be a little less pronounced since the emitter is not a point but an area, so not everything could possibly be parallel and things will be a little smudged. But still. A perfectly focused LED should have a donut hole in the beam. So basically it’s a sign of good focus and actually desirable?