option 1 will give me 4716 lumens per sq ft (1 250 watt hps) option 2 will give me 5488 lumens per sq ft ( 2 150w hps lights) option 3 will give me 4391 lumens per sq ft (16 23w watt cfls) my cab is 16 inces deep 52.5 inches wide im leaning toward using the 2 150w hps due to the 5488 lumens per sq ft and also better spread of light across my cab. also if i due the 2 150w hps can i use 1 300w digital ballast instead of 2 magnetic 150w ballast. i will be growing one plant via the scrog method i want to use the 2 150w hps bulbs but i want a digital ballast. can i use a 400w digital ballast? i doubt i can as there is 100watts not being used. im not familiar with the digital ballast and there design but maybe i can modify the ballast to output 300w. (capacitor change maybe) or a high voltage resistor circuit
I don't really know about the ballast, but the only concern I would have is heat. With two 150w HPS in that size box, heat may become a problem. But I would lean toward the two 150's for better production. As long as you can vent it, go for it.
i will be using a cool tube instead of the reflector shown. one like this except ill be building it. http://www.bghydro.com/BGH/itemdesc.asp?ic=HLRECT4&eq=&Tp=
Oh yeah 2 separate mag ballasts, you do not wanna try and get the voltage to split to from a high watt coil.
Not one of my digital ballasts survived longer then three years and i never saw any lower electric bills. Eventually i phased them all out. ive been through 4 600w future brights and three 600w lumatecs, 2 blue gen and one Purple gen. Any particular reason your set on digitals?
i voted #2 2 remoted 150w ballasts wont be very hot, so im not sure what the problem is with them and yeah, the 250 wont cover the rim of your plant in a 4.5' box anywhere near like the two 150s will. thats why i said option 2