Good thing reading further. All will be interested to know in explination. General idea, the
ballast switches at times slower than say a 50/60hz change to a normal
incandescent or even moving light lamp and more like a DC based
xenon lamp. When switched off as if a DC lamp, some deposits on one end of the electrode might be seen dependant upon what part of the switching between electrodes that
ballast/
power supply was switched off at remain on that end as a concept shown. Overall, unless such buildups are in the company of other stuff about the lamp or an extreme, it potentially is not a problem in that once the arc is struck again and
fixture warmed up in operation, the lamp will go back to normal mode and lamp back to normal operation. This the theory in not being accompaied by other stuff such as pinch/
globe crustie coning, pinch/electrode bubbling about the electrode, crusties about the electrode ends, crustie buildups and clouds about the fill pinch along with clouds about it
etc. to watch for. This along with normal type stuff such as
axial clouding, snow, froted
globe etc. due to wear.
Of note is this concept of elelctrode bubbles that normally is even say on a moving light is a way to tell age in general of the lamp but not persay a way to tell on a follow spot - why in
ballast type perhaps. Next, that such an observation of electrode bubbles building up on one electrode over another is seemingly something seen on newer lamps and not as much older lamps. Could there be something about the lamp that factors into this given the same
power supply?