Dan, just so we are all clear on the proper use. Did you test for extended run time with the head twisted totally in the non-focused direction, (and with the BB), so you know that way there is no risk of deformity? I'm trying to make sure that we all know if this happens to anyone's clear diffuser--it means for sure that they had it focussed down to some degree.
This caught me off guard because when I twist out the reflector (clockwise when looking at back of light), that center dark spot is so ugly, I would not have thought to ever use the light in that position....but indeed, when fully extended, the central "hexagram" pattern caused from the diffuser (that looked kind of bizarre) smooths out the way you would want a diffuser to work.
I'm sure it would have been hard to get a practical way to attach the glass diffuser, let alone extra expense of trying to get this pattern or frosted in adequate heat resistant non/discoloring multi-colored glass. The plastic diffusers work fine as long as we know this focus out requirement. I love my colored diffusers.
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