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Re: Cheap lights and dirt

>Date: Sat, 24 Oct 1998 23:01:59 EDT
>From: IDMiamiBob at aol_com
>
>I found a "Lights of America" shop light today for under $7 US on sale
>today.  
>
>1)  I got curious about why it was so lightweight.  I went looking for the
>ballast, and what I found was a little white thing about 2 inches square
and a
>half inch thick in the circuit where the ballast should be.  Is this one of
>those electronic deals I keep hearing about?

This is the El Cheapo version of an electronic ballast. It's a coil and
capacitor combo. 

>2) The box said it was compatible with all 48 inch T-12 bulbs, including 25,
>34, and 40 watt.  Will it run enhanced output 40 watt bulbs like the Triton?

Of you're lucky, it will run Tritons. However, the lumen output is reduced
compared to a tar ballast and the color temp is changed slightly (I have no
data about real electronic ballasts). My web page has detailed measurements
regarding this. Also, based on my experience, it reduces the life of Triton
bulbs. 

>3) I know that a standard 40-watt bulb has between 31oo and 3200 lumens
(or is
>it lux? I can't ever keep these things straight).  

They are rated in Lumens ("total light eneeryy emitted"). Lux is "Lumens
per square meter" and depends on reflector efficiency, distance form the
bulb, etc. Lux cannot be speced by the manufacturer.

>Is there a way to find out
>the actual rating for fancy bulbs that they sell at the the LFS and places
>like Pet Warehouse?  

Write to the manufacturer. My site has some caparative numbers.

>Andwhat about those bulbs rated for 8100 Kelvin and even
>10,000 kelvin?  Do higher color temps imply more PAR?  Or is the 6820 Kelvin
>of "sunlight" bulbs actually better? 

The "rating" and reality may differ significantly. Higher color temps imply
more blue and may or may not have higher PAR ratings (PAR considers all
energy useful for photosynthesis).
A specific color temp does NOT imply a specific spectrum. Two "5500K" bulbs
may have drastically different spectral components and will be be vastly
different than sunlight.


George Booth, Ft. Collins, Colorado (booth at frii_com)
  Back on-line! New URL! Slightly new look! Same good data!
    http://www.frii.com/~booth/AquaticConcepts/