Lighting HPS Wattage question for any gurus

[gradolabs]

I can see why this is confusing. I'd run the 600 with the autos and the 1000w hps with the photos... Autos would get 18/6 and if the photos are done vegging they'd get the 12/12 flip. That's 30 hours x 1.6kw = 48kw hours per day (you should get leds!!!) - most utility companies charge less than 20 cents per kilowatt hour... you'd have to look at your bill... but you are looking at around ten bucks a day in electricity.

As to why the photos would get the more intense light... they can use it. Autos aren't fussy and an extra 400w of light won't affect their yield as much as a photoperiod.

And lol... the unit of power electric companies use is the kilowatt hour... thats just you using a tv or whatever that draws a kilowatt for an hour.... multiply your kw x hrs... easy enough.

 

[TxOld Dude]

True that.

I think what we were trying to do was compare what A4's plants were getting, autos vs photos, in "volume" of light. Of course the formula is a bit BS, because the truth of it would be way too complex without knowing plant absorption rates, leaf mass area, etc, etc. This was just to give an idea of how much "light time" they were getting under a particular light than the photos. It balanced out, lumen-wise, but the autos would probably take way longer to give the same yield at 12/12 than 18/6. And because the autos run on their own internal clock, yield would suffer at 12/12 because the clock would run out before the same goal was achieved. Therefore a consistent 18/6 under 600w would bring a better yield within the allotted time than 12/12 under a 1000w, even with combining the lights at 12/12. IMHO. Would that be correct?

Fish

 

[A4]

Well, we will know in a month or so how it is going to do because I left one auto in the 12/12 tent with the 1000W light and moved the remainder to the 600W tent on 20/4. I couldn't resist comparing the results.

 

[TxOld Dude]

Experimenting is where all the fun's at! Til it's time to SMOKE IT!! Muahahahaha!

:smokebuds:

 

[Kozminski]

And plus you could grow perpetual with 2 rooms, one for the autos and vegging photos, and one for flowering the photos. Start seeds or clones every so often and harvest all year round!

 

[TxOld Dude]

Oh BTW, we will be expecting pix. Hmmm?

:stylez rasta smoke:

 

[TxOld Dude]

Just realized I screwed up the chart post in quoting lumens and it should be "footcandles" in the formulas instead. Could have been a brain cramp, but as long as it took to notice, that was a brain fart!

Adjusted...

Ditto that. Light absorbtion rate would be the factor. But who can tell that without being a biologist! LOL!
Rather than wattage, do a lumen chart assessment including bulb type vs. distance from tops (actual lumens) multiplied by time (hours) and compare the two. I threw the MH one for grins.

Just for shitz and gigglez, here's an example.




No, it's not completely correct without an absorption rate and the numbers are not on a "per hour" basis. The chart numbers are based on an "incidental", in other words, at the moment of measurement. But you get the idea.

600w HPS actual footcandles @ 12" x 18 hrs = "A"
vs
1000w HPS actual footcandles @ 12" x 12 = "B"

Daily exposure
29,285 FC x 18 hrs = 527,130 FC per day (600w) "A"
44,563 FC x 12 hrs = 534,756 FC per day (1000w) "B"
the variance = 7,626 footcandles (or 135 watts worth of CFL @ 2700k) in favor of the 1000w light on the schedule specified.

Of course, then again...
MORE IS BETTER! :stylez rasta smoke:

With both would be a total of 73,848 footcandles. With more light = better penetration to the lower nodes = more and bigger buds!!
The gains definitely warrant the cost! IMHO...

Fish