Further to that, that ballast and lamp holder can be hung up high and only loses 6% of it's intensity from 10 meters high to the ground which is impressive.
I can see using one of these with a light rail moving no more 25cm each side which allows the light to penetrate on different angles to create more intensity.
Plus did I mention, a DE ballast like this one has ultra high frequency compared to a single ended bulb ballast that's only high frequency.
Half the people on here are either using LEDs which can't produce shit compared to a HPS.
And the you have DE HPS, in particular Gravita DE HPS at ultra high frequency.
Plus the reflector on this unit is the reason why the light intensity is so much from top to ground.
So yeah, 3 pounds using one these using the correct methods is very possible.
I'm going back to growing soon and I'm starting off with a
Gavita Pro 1000e DE