This is the typical scenario of new lamps during the first ±120 minutes of operation (each time the lights are turned on).
The lamps eventually become stabilized over time, which is why some swirl, others do not.
Ambient Temperature may have bearing on this effect also.
Looks like a Cork Screw is spinning inside the Lamp, doesn't it?
Most apparent in the mid section of the Lamp, but does extend upto 2" from the ends of the Lamp (the Cathodes are set in
about an inch, and Ionization takes place past the Cathodes).
The Conical spins vary from time to time, but normally run in one direction in a given Lamp.
Spins may be fast, then slow, then stop completely - retaining their Conical shapes - then begin moving again.
Some Conical twists are very narrow, others wide.
Sometimes there's reflected waves that push back against the fundamental waves. These are really cool to watch, because it's
a visual example of Harmonics, along with Echoes in sounds!
With Rapid Start 2 Lamp Magnetic Ballasts (Hot Cathode Operation), the waves in each Lamp will be in opposing directions -
meaning when one lamp has a wave moving to the left, the other lamp has a wave moving to the right.
It looks like a "Slinky Spring" is flowing through one Lamp, then through the other one.
Very neat Phenomena
Edit-ted tew cuhhreckt sum speleeng air-errs
[This message has been edited by Scott35 (edited 01-05-2004).]