Sylvania 400w SON-T U.S.A vs Europe: Ignition & Full Power

Two Sylvania 400w tubular clear high-pressure sodium vapour lamps.
The top one is made in Belgium and the bottom lamp is made in the US.

Again it's interesting to note the differences between the pair. From the obvious outer envelope shape and the shorter overall length to the different LCL and the frame construction.
The arc tube end seal technology looks pretty similar.

The glasswork seems to be better on the Belgian lamp, the US lamp has quite a lot of visible striations.

Both start with a nice white light but it doesn't last very long and there is a lot more purple to it.
Both lamps quickly run up to a lovely golden yellow but the US lamp does seem slightly more yellow and possibly slightly less red content.

24,000h
52,000lm & 50,000lm
2050k & 2100k