2013:The year of White Led Horticultural Lights

stardustsailor said:

I agree with both statements ....

Still when i.e. one uses -massive amounts of - high CRI warm whites,
that peak around 630 nm ,then
the deep red part has to be supplemented ...

And no ..
That's what I thought too ,at start ...
That red wls above ~650 nm are mainly used for photomorphogenesis ....
Well ....Not ,exactly ....
After seeing the difference between ~620 reds and ~640 nm reds (Astir panels ) ,I was pretty much
convinced ,that deep red wls ( ~640- 660 nm ) ,promote a massive flowering (* or fruiting )....

They just have to be used correctly ...
(Easy thing to say,only ....Doing so, is kinda tricky.

In certain "shape"_with 'valleys' and 'peaks ' _,regarding the wanted "effect " or "goal " ....

Click to expand...

What exactly is so "tricky" about it? Are you keeping some sort of secret knowledge from us? Why not share what is so mysterious about how to use the wavelengths correctly with everyone?

Fonzarelli said:

Are you saying that 630nm is deep enough for Pffr conversion and Emerson effect? How do we even know that the Emerson effect applies to cannabis?

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I have posted this in many places, including the The Profs thread. Although 1year old, it's what I go by, until it proves false: (i.e. 630nm red is ~95% of the PSR of 660nm, AND they currently still have ~20-30% greater radiometric efficiency - as well as being cheaper than the deep reds - so there's more 'bang for the buck'):

cannabis as all other higher land plants working with the same photosynthesis process. nothing special here.

adverse effects from red or deep red?
here is the solarspectrum over the seasons

and know start thinking

guod said:

cannabis as all other higher land plants working with the same photosynthesis process. nothing special here.

adverse effects from red or deep red?
here is the solarspectrum over the seasons
View attachment 2661474
and know start thinking

Click to expand...

Exactly, there is so much red in sunlight and it doesn't do damage even for seedlings.

PetFlora said:

I have posted this in many places, including the The Profs thread. Although 1year old, it's what I go by, until it proves false: (i.e. 630nm red is ~95% of the PSR of 660nm, AND they currently still have ~20-30% greater radiometric efficiency - as well as being cheaper than the deep reds - so there's more 'bang for the buck'):

Click to expand...

I'm well aware of your post. I see it every time you post it. LOL

I don't disagree with SPL's statement, but I still think 660 is the more powerful wavelength as in, more effective.

My garden has responded stronger to the 660 wavelength than 630 at equal watt usage.

my old apollo's worked great then i retrofitted a handfull 6500k white in too and it runs just about the same. the green is for the cartenoids and they are shit for energy conversion of light energy. in all sure white LEDs makes it more palatble for those who worried about lumen loss and didn't quite grasp the concept of targeted initiation of the chlorophylls. the bigger problem is making sure the plants have the extra co2 and food to make use of the excessive light energy provided

Fonzarelli said:

This company seems to have grip on their lights, but I do not see a SPD for any of their "supreme" spectra.

Do you have a link? How is the customer supposed to know what they are buying?

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Their product is not meant for research .Their exact spectrums are trade secrets / proprietary ..
They are making some ( serious ) money out of it .You buy the leds .You grow.Got good yields ? Not many questions asked ....

A no-need-to-know information ,for lights which probably do what they're supposed to do, just fine ...

"Are you happy sir with the light ? "
"Ohhhhh,yessss! "
"Then you do not need to know further details.Our Secrets of the Trade ."

Something like that ,I guess ....

Fonzarelli said:

What are these "adverse effects?"

Need to know or it's just a theory.

Click to expand...

No it's not a theory ...
Without going deep into details ..:

-Prolonged exposure / high flux causes detoriation of PS II / ChB (mostly on young plants ).
-Prolonged exposure / high flux causes photoinhibition,increase photorespiration and reduces severely stomatal aperture .
-Prolonged exposure / high flux causes internodal stretching ,probably due to Auxin-Gibberellin unbalancing (mostly on young plants ).
-Prolonged exposure / high flux accelerates photo saturation .

Just some ....
When : are used excessively while vegging

Fonzarelli said:

Are you saying that 630nm is deep enough for Pffr conversion and Emerson effect? How do we even know that the Emerson effect applies to cannabis?

Click to expand...

No I'm saying exactly the opposite ... That deeper reds are doing ,especially that ...

Emerson Effect applies to almost all higher C3 plants ...
At least all those that have two different photosystems ....Meaning ....~99.99999999999999 % probably ....

(Excuse me ,but I've to ask this .....
Do have any basic plant biology knowledge at all ?
'Cause ,specially this question(about if Emerson Effect applies on mj ) ,
'indicates' that you probably lack that basic knowledge ... )

Emerson effect

(enhancement effect) The observation (made by Robert Emerson in 1957) that photosynthesis, which proceeds very slowly using light of 700 nm wavelength, can be greatly increased when chloroplasts are also illuminated with light of shorter wavelength (650 nm). This was a surprising observation as it was then thought that light absorbed by the chlorophylls and other pigments was all passed on to a small percentage of chlorophyll a molecules (the energy trap) absorbing at 700 nm. This and later work indicated a second energy trap absorbing at 680 nm. See Photosystems I and II.

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The observation of " Emerson effect" revealed the existence of two different photosystems ,
inside chloroplasts of almost every higher green plant ...
......
Now ,you know that it applies for almost all plants ....

Fonzarelli said:

What exactly is so "tricky" about it? Are you keeping some sort of secret knowledge from us? Why not share what is so mysterious about how to use the wavelengths correctly with everyone?

Click to expand...

No <I'm not hiding something ...
Tricky thing as when has to be used ,for how long ,at what flux and in what ratio/relation with rest wls ....
If we knew all that (and many others ) we would not have been having these kind of conversations ....
The near to perfect mj growing spectras would 've been already known to us ....

guod said:

cannabis as all other higher land plants working with the same photosynthesis process. nothing special here.

adverse effects from red or deep red?
here is the solarspectrum over the seasons
View attachment 2661474
and know start thinking

Click to expand...

Yeah ...But where exactly ?
From which part of Earth are those measurements ?

It seems somewhere on Southern Hemisphere ....

Plus that as you already know some led lights have totally "unearthy " red heavy spectrums ....

Way more red than rest of wls ....
Plus the stable light regime of indoor grown plants ,..
and many more factors .....

With leds (specially monochromatics ) is way easy to overdo it ...

Leds do not move ,neither change spectrum during the day ....neither output power ...
So yes ...Adverse effects from reds ...
If and only if : are used excessively while vegging
.....
I'm not the one who saw them first you know ,guys ...
First I've been reading about them and later (much later ) I 've experienced them, first hand ...

Damnecro said:

my old apollo's worked great then i retrofitted a handfull 6500k white in too and it runs just about the same. the green is for the cartenoids and they are shit for energy conversion of light energy. in all sure white LEDs makes it more palatble for those who worried about lumen loss and didn't quite grasp the concept of targeted initiation of the chlorophylls. the bigger problem is making sure the plants have the extra co2 and food to make use of the excessive light energy provided

Click to expand...

As this is the only thing needed for plants to thrive ,huh ?

You're saying that targeted initiation of the chlorophylls ,is enough ,for great yields ?

Or that they haven't tried in the past "making sure the plants have the extra co2 and food to make use of the excessive light energy provided " ?

stardustsailor said:

Yeah ...But where exactly ?
From which part of Earth are those measurements ?

It seems somewhere on Southern Hemisphere ....

Plus that as you already know some led lights have totally "unearthy " red heavy spectrums ....

Way more red than rest of wls ....
Plus the stable light regime of indoor grown plants ,..
and many more factors .....

With leds (specially monochromatics ) is way easy to overdo it ...

Leds do not move ,neither change spectrum during the day ....neither output power ...
So yes ...Adverse effects from reds ...
If and only if : are used excessively while vegging
.....
I'm not the one who saw them first you know ,guys ...
First I've been reading about them and later (much later ) I 've experienced them, first hand ...

Click to expand...

It's known that excessive red light will stunt growth. This is what is wrong with most panels today.

stardustsailor said:

No I'm saying exactly the opposite ... That deeper reds are doing ,especially that ...

Emerson Effect applies to almost all higher C3 plants ...
At least all those that have two different photosystems ....Meaning ....~99.99999999999999 % probably ....

(Excuse me ,but I've to ask this .....
Do have any basic plant biology knowledge at all ?
'Cause ,specially this question(about if Emerson Effect applies on mj ) ,
'indicates' that you probably lack that basic knowledge ... )



The observation of " Emerson effect" revealed the existence of two different photosystems ,
inside chloroplasts of almost every higher green plant ...
......
Now ,you know that it applies for almost all plants ....

Click to expand...

I directed this question to PF because I wanted to get his view on WHY he thinks monochromatic 630nm works better than 660nm. I want to know if PF thinks that 630nm will work for the Emerson effect equally to 660nm and also if he thinks that 630nm is equally effective at converting Pfr back to Pf.

OR, does PF think that 630nm is more effective for photosynthesis.

And no, I have ZERO knowledge when it comes to biology.

I also purchased my spectrometer from a gumball machine.

Why all the downtalk dude?

Fonzarelli said:

It's known that excessive red light will stunt growth. This is what is wrong with most panels today.

Click to expand...

If this is true then the Hans panel would not be a great veg panel....... out of the 33 leds on the panel 29! are R/DR and its absolutely creates compact/ tightly stacked plants on full flower phase.......I know this personally.

Then it's probably not excessive right?

Does his panel have any 730-740nm in them? I think he refers to the as "Cherry Red" LEDs.

http://www.skyeinstruments.com/wp-content/uploads/The-importance-of-the-Red-Far-Red-ratio.pdf

"excessive red photons, growth is stunted"

See for yourself

Fonzarelli said:

Then it's probably not excessive right?

Does his panel have any 730-740nm in them? I think he refers to the as "Cherry Red" LEDs.

Click to expand...

Yeah his description is off.....their are NO FR leds on the panel just two DR lumiled rebel 660nm, rest is 630nm cree xp-e

It is amazing to me that just 4 royal blue xt-e's can offset any stunting caused by the massive amounts of red on the panel.....it's a great design with those wide panel reflectors......

Fonzarelli said:

I directed this question to PF because I wanted to get his view on WHY he thinks monochromatic 630nm works better than 660nm. I want to know if PF thinks that 630nm will work for the Emerson effect equally to 660nm and also if he thinks that 630nm is equally effective at converting Pfr back to Pf.

OR, does PF think that 630nm is more effective for photosynthesis.

And no, I have ZERO knowledge when it comes to biology.

I also purchased my spectrometer from a gumball machine.

Why all the downtalk dude?

Click to expand...

Listen ,you 've to excuse me if it sounds like "downtalk " .....
I did not really expect from you to ask about Emerson Effect and if it applies on mj ....
I trully apologize if it sounded kinda "weird " ,but I guess I already have no love for the people or the community ...
I'm not that "politically correct " kind of a person ..I'm kinda ...."raw " ...
But not cause I mean any "bad" or" evil " ...
It's a way to "shake ",nevertheless ...

I also purchased my spectrometer from a gumball machine.

Owning a spectrometer is a great aid ,but proves or means nothing ,about a person's knowledge ....


Now as for the rest about reds ...

Briefly : Red spectrum has to be "complete " .Better that way ....Plants grow better under a full red range ,
rather than targeted at ~620-630 or ~640-660 or 670-700 nm ...
Better have a complete ~600- 700 range and as power-even as possible ..(at least in the range 620-660 nm ) ...

.......

As for the Phytochrome conversion .....

Look at chart ...
At 630 & 660 nm ....
PSS : 0.89 ...Exact same .....

(Phytochrome Photostationary State : amount of Pfr divided by total phytochrome ( Pr +Pfr ) ,induced by radiation of certain wavelength )

....
And a " quiz " .....

LIGHT-EMITTING DIODES TO

UNDERSTAND THE FLOWERING

RESPONSE OF A SHORT-DAY

STRAWBERRY

Takeda and Newell (2006) have observed that short-day strawberries that are grown in

the greenhouse under long-day conditions can be induced to flower in the fall without

exposure to cool temperatures or short days.

This unexpected result was attributed to very high planting density (200 plant/m2)
of the plug plants in the greenhouse. Takeda et al.

(200 stated that broad spectra light was absorbed by the canopy, but only wavelengths greater than 700 nm were being detected by

the crown, resulting in an F< 0.2 at crow level. It was hypothesized that the earlyflowering response was phytochrome-medi- ated.
To test this hypothesis, high-densitystrawberries were established under long daysin a greenhouse (F= 0.62)
and then trans-ferred to a controlled environment chamber with broad spectrafluorescent lamps (F=0.66) under long-day conditions (16-h light/8-h dark).
A strand of low-output red LEDs(lmax= 662) was used to illuminate the crownand increase theFto 0.75 (Fig. 6).

This treatment was applied for 28 d and then the plants were transplanted in the field under a high tunnel production system.


After 2 months under high tunnel con-ditions,83% of the plants without the sup-plemental red LED treatment were flowering,


whereas less than half (47%) of the plants with the LED treatment were producing flowers.

These data strongly suggested the maintenance of the vegetative state of the crown under short-day plants is under phytochrome control and suggests that manipula-
tion of the crown light environment using LEDs to promote earlier flowering could be a tool to increase off-season production of strawberry.

Click to expand...

What do you understand from that ?
What do you make out ?
Was the red 662 nm beneficial during vegetive stage of strawberries ( a plant closer to mj than lettuce ) ?

http://hortsci.ashspublications.org/content/44/2/231.full.pdf