Not an usual sight

I use a Schréder DZ15 to test many of my E39/E40-capped HID lamps and for my lighting projects. This streetlight luminaire was once popular in Europe during the 1980s and 90s, particularly in France and Spain. On paper it is compatible with 150-400 W HPS, 250-400 W MH, and 250 W HPM lamps. I've used it with arc lamps rated up to 1200 W (with a suitable adapter) and here it is fitted with a 2009 GE HR400 clear mercury lamp, one of the last produced in Europe (Hungary, at the former Tungsram plant in Budapest). That's a combination that was certainly never seen in the wild, especially given that clear mercury lamps are no longer used in streetlights here since the 1960s. Despite the abuse the DZ15 has remained in an excellent state, a testament to its quality and robustness. The picture below shows the HR400 at full regime.