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Re: watts vs. lumens

At the end of his authoritative post,Wright writes:

<snip>> Too many lumens per Watt always
>  cheats the plants out of energy *they* need, for the manufacturers of "cool
>  white" tubes have gotten really very good at not wasting red and blue light
> we
>  don't see well, anyway.
>  Red and blue are about 20% of the output of a very high lumens/Watt tube.
>  Unfortunately they are about 80% of the photosynthetically active spectrum 
> of
>  our plants. That's why plants *can* grow well under "cool white" lights.
>  just may need several times as many Watts of it.

Odd, Wright.  Explain to me the Triton tube.  It is engineered to put out the
most light at the frequencies plants use most.  Yet, it's lumens per watt runs
somewhere around 50% higher than normal cool whites.  This is contrary to what
you are saying here.  The truth is, some bulbs put out more light per watt
than others.  More light visible to human eyes, and also more light that
plants can use .  That means you can get better growth with these bulbs using
the same amount of power.

Wherein lies the heart of my conundrum.

Bob Dixon