In article , Karl Townsend
wrote:

I moved away from flouresent because you can not get enough light
intensity like you can with the high pressure sodium.

Jeeze, what are you going for? 100,000 lm/mm2?

I tired to find numbers for intensity to compare to LED, no joy.

This grow light is about the same as the high pressure sodium street
lights you've seen. You can tell a sodium light by the orange hue.

Well, it depends on the pressure. Low-pressure Sodium lamps are
yellow, not orange. One sees these lights a lot.

I also recall people using sodium-calcium many decades back - these had
an orangish color. This may have been the original Lucalox design.

For the intensity level you are looking for, and efficiency, it would
be hard to beat high pressure sodium. LEDs just aren't there yet.

Joe Gwinn