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Re: Lights

> ------------------------------
> Date: Fri, 21 Dec 2001 16:32:17 EST
> From: MStark7789 at aol_com
> Subject: Lights
>  Hi
>    You people seem to have all the right answers so here goes.

And free advice is worth every penny! ;-)

>   If I have a light fixture that has an ANSI rating of 6800 lumens a CRI 
> rating
> of 84 and K rating of 6500 would I double the intensity if I added another or 
> just
> spread it around? By this I mean would the light be brighter in a given area 
> or
> would the area of illumination just be larger? Hope I made myself clear.
>                                      Gary    fla.

The results would depend a bit on the design of the reflectors, but generally
you would double the available light. The reflectors and lamp location would
determine exactly where it went, tho. [The numbers you give have nothing
whatsoever to do with those factors.]

That said, a CRI of 84 is not great, and the light is likely to not look very
pure "white." Mixing with a 5000K lamp can sometimes help that situation, even
if neither has a CRI of 90+.

Look for somewhat *less* lumens per Watt (all other things being equal) to get
the broader spectrum that plants can use effectively. Lumens is a human
psychophysical measure that is heavily biased toward green. Reds and blues are
not weighed heavily in lumens, but plants need them, anyway.


Wright Huntley -- 650 856-4245 -- 879 Clara Dr. Palo Alto CA 94303

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