What the best way to mount DE MH bulbs?

[Rascal]

I thought I remember reading it was better to mount them perpendicular to your tank, but most commercial fixtures I see have them parallel. I currently have mine parrallel, but since I am going to redo my canopy soon I figured I might as well try to get it right this time - the 3rd, and hopefully last, canopy build.

 

I guess my question is really which direction do they throw more light, longitudinally or horizontally? I looked at Sanjay's charts and I can see it is not a perfect square of light distribution but I can't figure out which way the bulbs were oriented in relation to the charts.

 

Any help would be greatly appreciated.

Edited February 8, 2007 by Rascal

[jason the filter freak]

I would think you get better light distribution doing it parallel, as well as I have also observed that most if not all comercial fixtures are parallel.