At what distance did you photograph them? That makes a great difference ya know. All properly made parabolic reflectors will exhibit a donut hole at
close range (say a few inches from the emitter). I suspect that you stuck
the camera right up to the light and photo graphed it right?
Here are some examples of how the distance makes a difference.
Here I took a shot of a quad mag at about 1-2 feet:
Notice how you can't see the yellow phosphor in the emitter on all four?
Well back off to 10 feet and heres what you get (with 10x lens):