Went to fix a 70W HPS fixture (ignitor internal to lamp) at a neighbors the other day after he mentioned it had stopped working. Said it had recently gone out and put a new new-old stock lamp in himself, but that did not last long until it went out again, so I went over and swapped the bulb over...
So today I did a little experiment and thought I would see what would happen if one powered up a 70W HPS bulb with an internal ignitor directly on the 230v mains without using a ballast.
Sadly not much happened other than a brief flash for a fraction of a second before the MCB for the circuit...