Re: Fluorex Lights - or How Too tell which Lights Yield how much Light

["S. Hieber" <shieber at yahoo_com>]

Someone pointed out:

"Anyone who wants to know how much light their fixture
will produce
must know the ballast factor of the ballast, the fixture
efficiency and the
lamp lumens. If you wish to know how much plant usable
light will be
produced you have to multiply the lamp lumens by a
correction factor which
depends on the actual spectrum of the lamp. There is no
other way to do this
without taking some pretty sophisticated light
measurements."

I hope this doesn't scare off any folks new to aquatic
gardening, or make them awestruck with the task that lies
before them.  I have seen that happen to a number of
prospective hobbyists.

That above quote is, well, technically accurate but not
quite realistic.  Some lumens are usable by some plants and
others are, depending on wave lengths, so even more data is
needed ;-).  

Actually, what I want to remind folks is that it's
unrealistic for a bigger reason.  It's sort of like saying
you can't tell how much gas mileage a car will really get
unless you take samples and operate on the roads you
normally drive, in the ways you normally drive, do some
research on the gasoline, the engine, and a few other
things -- if you really want to know what the car will do. 
 That's sort of true but very impractical, certainly
unrealisistic.  Even before the government required
standardized ratings, you could get a good idea about gas
guzzlers and gas misers without doing extensive research. 
Of course, the easiest thing was to ask friends that had
the cars are that knew a lot about cars.  Most folks aren't
in positions to do new research nor find ballast factors,
quantified reflector assessment values, bulb lumen ratings
(especially those that your plants can use, and which are
set by established standards anyway) or even get
assessments of bulb lumen output generally, for specific
bulbs.

It would be nice if manufacturers used straightforward,
standardized ratings, but they don't.   And with
fluorescent bulbs, ratings can only work with specific bulb
and ballast combinations.  Although it wouldn't be too hard
for ballast manufacturers to include with a ballast a list
a standardized ratings for a wide variety of particular
bulbs (call your congresswoman or congressman).  

Wpg will get most folks pretty far, especially when
comparing roughly similar lamps (whatever roughly means). 
Further help can be had be asking knowledgeable friends or
Mail Lists, or when practical, researching the other data
mentioned like ballast factor, power factor, efficacy
factor.  But then you have to fold all that info together
with the cost and make a subjective decision about value
and "right choice."

The deep data method is a good way to compare lamps if you
can do it.  But it's not necessarily the best way because
it not as practical as some of the other methods.  It's
certainly not a necessary method for successful gardening.

BTW, I would stay away from anything made by Lights of
America.  I personally have found them to generally make
cheap, somewhat crappy items, that sell for cheap prices
but which are poor values. Just my opinion.

imo,
Scott H.

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