Philips HPL-R 240V 125W
This is the very first frame of video after the arc struck. It's not quite stable yet.
The lamp in question is a Philips HPL-R 240V 125W reflector, ES (medium) base.
This is the very first frame of video after the arc struck. It's not quite stable yet.
Here's the video
Click here for the video (Realvideo) if you don't want to use the mp4 version. It's about 4 minutes long- the time the lamp took to run up to full brightness. The most interesting bits are the beginning (of course) and the end where the lamp it switched off, leaving just the arc tube and electrodes glowing. At the beginning you can see the colour of the phosphor change as the arc gains strength and temperature, and you can just see the dark deposits of mercury on the inside of the arc tube vaporise as well.