[StirCrazy]

Well now that I have a MH bulb I can do some comparisons between MH and PC lighting. I was quite surprised in what I found and I am sure some of you will be also...

First off the line up, I am running a 10000K, 96 watt PC (this is the one I am testing) and a 175 watt Ushio 10000K MH. For positioning I placed the PAR sensor 9" below the bulb (in the water) I would have gone 12" but the design of my sensor mounting prevented me from doing that. it also prevented me from getting directly under the MH bulb, so I suspect when I redo this test when I make a new mount the MH #'s will be a little higher.

So to get an idea of where the sensor was in relation to the lights...
1, 9 inches directly below the PC and
2, 9 inches below and 4 inches to the left from the MH.

With just the PC on I got a score of 192.75 PAR (150 PAR is considered the minimum for SPS)

with Just the MH on I got a score of 255.35 PAR(I suspect this will be between 300 and 350 when I retest)

with Both on I get a score of 447.18 PAR

a couple interesting (or maybe not) tidbits, the MH is 1.8 X the wattage of the MH, but the light is only 1.3 X more (even if we assume 325 for a new score on the second test it will be 1.68 X )
this shows that the PC is more efficient than a MH per rated watt.

Just thought I would throw this all out for anyone who is interested...

Steve

[ 21 August 2002, 19:03: Message edited by: StirCrazy ]