Ian, Hats off to you for doing the thorough analysis. This makes total sense and I was getting suspicious of this late last night as well. I will try putting black tape around the perimeter of the opening in the negative stage just above the bellows and see if I can get rid of the stray light.
Originally Posted by Ian C
Am I missing something in the negative stage? How come others with LPL 6700 doesn't experience this?