These photos are of a brand new quad of Shuguang EL-34 B's. They probably have less than 40 hours on them. Please excuse my ignorance (I am a tube noob), but I just noticed something that I do not think I had seen before. It may or may not be perfectly normal. What do you make of the following:
This is how they look with normal lighting:
And this is how they look in the dark (please excuse the soft focus... I had no time to play with the tripod position):
Notice that the top area seems to be "faded/fading". The upper area/coating is darker in the center of the tube's top (above the getters), but considerably lighter on the sides/edges. The color is basically a light gray, but not white (I believe that would be a sure sign of trouble). The tubes look perfectly fine (at least to my untrained eye) otherwise, and there are no audible issues as far as I can tell.
Is this normal? Or did I get a bad quad?