Another reason to move away from HPS

the OP's title and comment in his first post is aimed at the PDF he linked to..........the PDF is the reason this thread exists and should be what we discuss not" whats the best bulb?"[like rusty i use the cheapest] or "when/will HID's be outdated?[only HPS/MH in my room for now]. I do not seek 1% more THC 2% more CBD's or 8% more trichomes but knowledge and information. i already know that UV can have beneficial affects on some verities of cannabis. i also know that it can be useless on others and dangerous to work with:beatdeadhorse: ........................this is what i consider " on topic" Rusty " I believe the yellow spectrum is absorbed and converted by the chlorophyll B pigments, but would have to double-check."THANKS RUSTY . could any of you LED growers blast a bud with some yellow during flowering to see if it makes a difference in cannabis ?

"I will stick with my HPS and you can use your arguments to grow your plants. "

Love dat! Thanks.:thumbsup:


MHO?

Yellow light is not harmful, it is just less efficient.
(Or effin efficacious, if yer picky 'bout dat kine t'ing):D
Plants can up, and down convert to get what they need, but that comes with a cost.

That is not a big problem, just use more of it and the gals will grin and grow.
Might even be able to use green light, but it would take a metric shitload of it.:)

I've found that it takes almost twice the power usage for hps not including ballast and cooling.
And that is the main reason I use LEDs.
Power is north of half a rock per KWH here and it's a long term expense! :(
The expense of leds amortizes in one grow on da Islands.:cool:

Your milage will most likely vary.

In places where electricity is still relatively cheap, It might take 4 or 5 grows to amortize the cost of LEDs
(Even home-built, they ain't cheap)

If that were my situation, I'd simply use HPS/MH and just crank up the wattage for equivalent growth.
(Might feel jus' a little guilty 'bout da waste, but da good bud he'ps wit' dat, yah?).:jointsmile:

Aloha, Y'all
Weezard

YouTube - kennebbiss's Channel

Check out my youtube channel and you can see it progress from Veg to Flowering. It's looking real good.

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Originally Posted by Weezard

Yellow light is not harmful, it is just less efficient.

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well...the scientists who conducted the test found yellow and uv harmed the plant they were growing . does this damage occur in cannabis ?in the case of UV we can safely say YES but MJ counteracts or responds to UV in a way that many growers find beneficial. does yellow[600nm] cause a similar response in pot ? I don't know...maybe/maybe not but if someone could point me to a narrow band light source centered at 600nm i would be willing to run a trial to find out.I don't need mega watts just something to hang between 4 18" buds as a supplement.

Quote:

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Originally Posted by seventhchild

well...the scientists who conducted the test found yellow and uv harmed the plant they were growing . does this damage occur in cannabis ?in the case of UV we can safely say YES but MJ counteracts or responds to UV in a way that many growers find beneficial. does yellow[600nm] cause a similar response in pot ? I don't know...maybe/maybe not but if someone could point me to a narrow band light source centered at 600nm i would be willing to run a trial to find out.I don't need mega watts just something to hang between 4 18" buds as a supplement.

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That's what I like to hear!
If we are not sure, we try sumpin an' see what happens.
Goodonya!:thumbsup:

Dang!
You made me go slog through that entire turgid, repetitive, PDF!
There's 10 minutes wasted.


A critical read of that PDF, indicates that wheels may get spun to no avail.:D

It starts out with what I consider to be a a weak statement for their case. (bolding is mine)

"primarily associated with UV rather than photosynthetically active light wavelengths."

Then another weak statement;

[align=left]"Interestingly,
our result showed that the quantum efficiency of
photodamage has a small but apparent peak at yellow[/align]
(600 nm) wavelength in the visible light region"

Then they admit that other studies found no yellow peak and they offer several hypothesis for their conflicting results.":wtf:

"The spectrum
[align=left]of photodamage efficiency shown in Arabidopsis
intact leaves had no visible light peak (Sarvikas et al.,
2006). The difference with our results may be due to a
different content of leaf pigments (the leaf used in our
study might have higher amount of photosynthetic
pigments or lower amounts of green-yellow absorbing
pigments such as carotenoids and phenolic compounds).
Further studies are necessary to verify this[/align]
hypothesis.":wtf:

This is not good science, my friend!

I would not waste any resources chasing the transient "pip" described in this paper.
You will note that they attempted to disable the plants, "damage control" .
Unless you have some lincomycin or chloramphenicol laying around, cannabis will simply repair any "damage", should any occur, and we will be none the wiser, yah?:)

In short, this is a non-issue.
Might even be a fnord;)

Aloha,
Weezard

[attachment=o251172]

Lately???

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Originally Posted by Weezard

Dang!
You made me go slog through that entire turgid, repetitive, PDF!

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thats how i would describe it also
There's 10 minutes wasted.[/QUOTE] it only took you ten minutes ?? not wasted WEEZ ...........you took one for the team:thumbsup:
A critical read of that PDF, indicates that wheels may get spun to no avail.:D[/QUOTE]THANK YOU for putting your eagle eye on that PDF. most of us [myself included ] could only make head or tails of parts of it.after 45 minutes of searching the internet i could find no other studies that found damage caused by yellow light and will not spin that wheel any more, muchas gracias and Aloha

Quote:

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Originally Posted by irydyum

[attachment=o251172]

Lately???

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And my favorite

You're a head
in a fnord
All the way:D

A.
W.

Bottomline: HPS does not kill...so...all you mf'ers with HPS...can go back to what you were doing....:thumbsup:

i don't no much about all that stuff yall are talking about, but i do no it's hard to beat the sun. got my girls outside tanning.