Inspected closely and on one end blew a small hole straight through the phosphor!

you need a measure current. keep in mind these tubes almost run about twice the current than normal F14 lamps. also what help to have a better picture is to have some background lighting that way photo not so dark looking.

I'm afraid there's little I can do about the lighting. Dropped my exposure down to the max to get that picture as the tubes are quite bight and the details are swamped out and I don't think i'll be testing these on anything else until I have a meter again.

The 14W seemed happy enough on a 20W 2' ballast. Was running at around 0.3A (best I can do, my clamp meter only has 0.1A resolution) though the ballast was humming more loudly than usual, probably objecting to the lower than usual voltage drop. I reckon these were run on fancy HF (probably dimmable) gear originally and did flicker and swirl madly for the first few minutes before settling down. The phosphor seems to have quite short persistence which in conjunction with the short tube makes flicker quite pronounced.

Yeah my 30W's where flickering and swirling like a witches brew on the 65W. I also reckoned these ran on some fancy proprietary gear. A triple fitting for these is well over 500 quid used. I ran the 14W fine on a 30W in series with my 3000K 14 tube. The tube ran fine but the ballast was heating up fast. These 30W tubes need some proper warm up time I reckon. I can see from the dotting across the phosphor these tubes have a LOT of mercury that has to evaporate. They are difficult to ignite. The one with the shot emissive coating came on first taking the full impact only darkening the already dark patch on the side. No idea how i'm gonna drive these. Gonna have to wait til my new meter arrives and then piss about with them.