To continue on a thread that doesn't seem to exist any more.... I went Home
Depot, bought some full spectrum florescent light bulbs (they have 4' and 8'
in 2 brands) @ $8.99 each and installed them in our kitchen light which
takes florescent tubes. Since we just did it I don't know how it is going
to work. I gotta tell ya though that the lighting is really strange. It
actually looks blue... sky blue. The other lights in the house look
yellow-red in comparison... It is odd because it looks really much brighter
but the watts are the same as what we had.

DK

I need to correct that to "I went TO Home Depot"... sounds as if I've gone
postal.... then again if I keep spending as much time in Home Depot as I did
last year I may go that way....


"D K" wrote in message
.net...
To continue on a thread that doesn't seem to exist any more.... I went
Home
Depot, bought some full spectrum florescent light bulbs (they have 4' and
8'
in 2 brands) @ $8.99 each and installed them in our kitchen light which
takes florescent tubes. Since we just did it I don't know how it is going
to work. I gotta tell ya though that the lighting is really strange. It
actually looks blue... sky blue. The other lights in the house look
yellow-red in comparison... It is odd because it looks really much
brighter
but the watts are the same as what we had.

DK

There's three things about florescent tubes:

They lose a lot of their ability to put out light in the first month or so.
So a 1 month old bulb of the same type will look dimmer than a new bulb.
They also slowly drop in the amount of light they put out. Florescent tubes
should be replaced every year. Most aquarium people who grow plants replace
them after 6 months because they just lose too many lumens. Compact PC
florescent lights (don't confuse with small florescent lights) don't have
this problem and last a very long time. They are expensive though.

The sun puts out full spectrum which means all the shades of all colors.
Full spectrum florescent bulbs put out specific shades of blue, yellow, red,
and green. So whereas the sun would put out 100 shades of green a florescent
bulb will only put out 3 shades of green. Plant lights put out mostly blue
and red and normal office lights put old mostly green and yellow (what
humans see best)

There's also a "temperature" of the bulb. Don't confuse this with heat, it
has to do with how we perceive the bulbs color. This appears to us as either
blue or red or a mixture (i.e. kinda violet). When you see something like
"5000k" it's the temperature. A lower number means it'll be more red. A
higher number means it'll be more blue. "Cool Whites" are higher temperature
and "warm whites" are in the lower temperature. Most full spectrums are
5000k.



"D K" wrote in message
.net...
To continue on a thread that doesn't seem to exist any more.... I went
Home
Depot, bought some full spectrum florescent light bulbs (they have 4' and
8'
in 2 brands) @ $8.99 each and installed them in our kitchen light which
takes florescent tubes. Since we just did it I don't know how it is going
to work. I gotta tell ya though that the lighting is really strange. It
actually looks blue... sky blue. The other lights in the house look
yellow-red in comparison... It is odd because it looks really much
brighter
but the watts are the same as what we had.

DK

The fluorescents that I bought were sold as "Full spectrum" Do you know how
different they are from the lights sold for SAD that are considered full
spectrum?


"Sam Hopkins" wrote in message
.. .
There's three things about florescent tubes:

They lose a lot of their ability to put out light in the first month or
so.
So a 1 month old bulb of the same type will look dimmer than a new bulb.
They also slowly drop in the amount of light they put out. Florescent
tubes
should be replaced every year. Most aquarium people who grow plants
replace
them after 6 months because they just lose too many lumens. Compact PC
florescent lights (don't confuse with small florescent lights) don't have
this problem and last a very long time. They are expensive though.

The sun puts out full spectrum which means all the shades of all colors.
Full spectrum florescent bulbs put out specific shades of blue, yellow,
red,
and green. So whereas the sun would put out 100 shades of green a
florescent
bulb will only put out 3 shades of green. Plant lights put out mostly blue
and red and normal office lights put old mostly green and yellow (what
humans see best)

There's also a "temperature" of the bulb. Don't confuse this with heat, it
has to do with how we perceive the bulbs color. This appears to us as
either
blue or red or a mixture (i.e. kinda violet). When you see something like
"5000k" it's the temperature. A lower number means it'll be more red. A
higher number means it'll be more blue. "Cool Whites" are higher
temperature
and "warm whites" are in the lower temperature. Most full spectrums are
5000k.



"D K" wrote in message
.net...
To continue on a thread that doesn't seem to exist any more.... I went
Home
Depot, bought some full spectrum florescent light bulbs (they have 4'
and
8'
in 2 brands) @ $8.99 each and installed them in our kitchen light which
takes florescent tubes. Since we just did it I don't know how it is
going
to work. I gotta tell ya though that the lighting is really strange.
It
actually looks blue... sky blue. The other lights in the house look
yellow-red in comparison... It is odd because it looks really much
brighter
but the watts are the same as what we had.

DK

"Sam Hopkins" wrote:

There's also a "temperature" of the bulb. Don't confuse this with heat, it
has to do with how we perceive the bulbs color.

It refers to the temperature a black body would have to be to create
that light.

You know red hot, white hot etc, that is the thing. If you could heat a
piece of steel to 5000 degrees K it would look like daylight, instead of
just red hot.

In summary, the higher the color temperature, the bluer the light.

fluorescent lights put out a full spectrum
http://www.natural-light.net/Comparison.htm
the difference is the intensity of light is not the same across the entire spectrum.
Ingrid

The sun puts out full spectrum which means all the shades of all colors.
Full spectrum florescent bulbs put out specific shades of blue, yellow, red,
and green. So whereas the sun would put out 100 shades of green a florescent
bulb will only put out 3 shades of green. Plant lights put out mostly blue
and red and normal office lights put old mostly green and yellow (what
humans see best)

here is a comparison http://www.natural-light.net/Comparison.htm
what is needed is intensity, which is why those boxes have multiple bulbs. Ingrid

"D Kat" wrote:
The fluorescents that I bought were sold as "Full spectrum" Do you know how
different they are from the lights sold for SAD that are considered full
spectrum?

this is only true for hot body.. for gas emission lights (fluorescent) that is not
true.
http://users.megapathdsl.net/~solo/w...m_physics.html
Ingrid

It refers to the temperature a black body would have to be to create
that light.
You know red hot, white hot etc, that is the thing. If you could heat a
piece of steel to 5000 degrees K it would look like daylight, instead of
just red hot.

No, it's true for bulbs too.
Nice article though, thanks Ingrid.
The color, as stated, is an indication of what a black body would be at that temperature.
Not that fact that the gasses are heated to 5000K and are emitting light at that temp.
I think you have the scale of color and the way the light is created confused.
After daylight the scale is estimated, BTW daylight is considered to be 6500K not 5000K
even though a lot of manufacturers call 5000K and 5500K bulbs daylight.
Most plants can convert light that is given in peaks and troughs (like artificial light) to
a useable form of energy so even though the broken down spectrum is very different than the
sunlight spectrum (which is smooth, no peaks and troughs) the plants treat it almost the
same as long as the color is similar.
Make sense?
Simon

wrote:

this is only true for hot body.. for gas emission lights (fluorescent) that is not
true.
http://users.megapathdsl.net/~solo/w...m_physics.html
Ingrid

It refers to the temperature a black body would have to be to create
that light.
You know red hot, white hot etc, that is the thing. If you could heat a
piece of steel to 5000 degrees K it would look like daylight, instead of
just red hot.

Simon O'Keeffe wrote:

Most plants can convert light that is given in peaks and troughs (like artificial light) to
a useable form of energy so even though the broken down spectrum is very different than the
sunlight spectrum (which is smooth, no peaks and troughs) the plants treat it almost the
same as long as the color is similar.

Yes, although for green plants (most common) the green wavelengths are
not terribly useful to the plant, being reflected to give it color to
our eyes.

there are only two main colors, blue and red that chlorophyl in typical plants use.
Ingrid

John Hines wrote:

Simon O'Keeffe wrote:

Most plants can convert light that is given in peaks and troughs (like artificial light) to
a useable form of energy so even though the broken down spectrum is very different than the
sunlight spectrum (which is smooth, no peaks and troughs) the plants treat it almost the
same as long as the color is similar.

Yes, although for green plants (most common) the green wavelengths are
not terribly useful to the plant, being reflected to give it color to
our eyes.

no... Ingrid

Simon O'Keeffe wrote:
Make sense?
Simon