Mass low-pressure sodium run-up.

Simultaneous run-up of every common standard SOX / LPS lamp: 180w, 32,000lm. 135w, 22,600lm. 90w, 13,600lm. 55w, 7,800lm. 35w, 4,550lm. 18w, 1,800lm. Low pressure sodium rules' monochromatic goodness :) The reason why they start pinky-red and take about 10 minutes to runup to full power is because when cold, the sodium metal is solid, so there is a neon-argon starter gas that heats up and vapourises the sodium so it can join the discharge mix. Low pressure sodium vapour lamps are the most efficient light source widely available with over 200 lumens per watt in some cases but are being supplanted by other technologies due to stupid EU regulations regarding minimum colour rendering as SOX lamps are a monochromatic light source. Music by Approaching Nirvana    / approachingnirvana   Song: Our last night. Buy the song on iTunes: http://bit.ly/RLahIL