I recently picked up an older generation E2D (500 lumen?) and expected the beam to be ugly with tint shift and all. However, the hotspot has this weird four-petal flower pattern. I noticed the emitter has a bow-tie dark spot. Now I expect shadows to be cast on the emitter when looking at it through the optic/reflector, but this dark spot doesn't seem to go away or change in shape when moving the head around and looking at it under different angles and lighting. Any ideas or experiences?