White Light LED and addition of Red and Blue light on plant response

VegasWinner

Well-Known Member
i hate to say the same but am just here to contribute. if you cant acknowlege that the lions share of youtubes you posted on the front page are biased and inaccurate i guess we dont have common ground to move forwar don.

knowing what we know about LEDs now, its hard to really give credence to a test of a light consisting of a sun system par meter and a spectrometer in a tent when your lights are 30-50% behind others in effiicacy on a real testing rig.

ive got no dog in the race as i dont sell fixtures or make absolute efficiency claims, i just try to get as much raw data out there so people can use it to build what works for them. i appreciate the thoughtfulness youve put in in the last few weeks in trying to raise the bar of info here, but some o fit is misguided at best. slick packaging does not make a light any better than the right spectrum of HQ components applied in a DIY fashion. weve learned so much over tha last few years that the science a lot of the light mfrs you rep are literally based on trying to match the mccree curve which we know has its limitations
You know I don't sell lights. But because I don't agree with a view makes me a DIC. Excellent why even bother any longer wasting my time here going back to work with real world.
 

CobKits

Well-Known Member
This is kind of a silly statement. DIY still uses the years of R&D the other guy did.
and moreso in some cases. there is no way that any one company has the number of grows that RIUers have done under all sorts of conditions here in the last few years. @Greengenes707 alone prob did more research on yields and spectrums than half of these companies, and thats before he even started a light company.

'industry standards' are great

open source development has proven to be at least as good in many many markets.

DIY is the linux of lights. anybody can roll your own but there is still room for people to sell custom distros with support, all operating on the same architecture and fundamentals
 

CobKits

Well-Known Member
You know I don't sell lights. But because I don't agree with a view makes me a DIC. Excellent why even bother any longer wasting my time here going back to work with real world.
just saying youre being awful nitpicky. if youre gonna post a bunch of youtubes from one of the most panned manufacturers on the first page of your thread, claim its a standard, and suggest DIYers are doing it wrong (whether sarcastic or not), as someone said, dont be surprised when seagulls show up at your picnic
 

Hybridway

Well-Known Member
I think that some of you are missing the point by focussing on quality components & efficiency. From what I read (maybe too fast) is that this thread is about spectrum. Those Kind led comparisons are bogus for PPFD readings but some do show you the spectral output.
Granted, the Chineese don't grow pot in their country so they've focussed their spectrums to veggies. Understandable. Now, American distributors got their hands on them (middle men) n tried selling them for MJ cultivation. OK, so a bunch of growers got beat. Not only for efficiency but also for lack of a true full spectrum, which is what our plants thrive on.
When I compared my Enhanced White spectrum to my Burple, the growth characteristics were noticeably different. The Burple grown buds didn't even fill in at all. Then again, not all burples are the same.
White hps has been killing it for years. Huge buds, surpassing the size of my enhanced white from what I've seen thus far. Although, my EW out yields & contributes to much higher quality. Might not be as big a buds but are way more G's per watt, & slightly more per plant & Sq'. Using 200w less per plant.
White light is necessary IMO. Enhanced white is even better as long as one can keep the efficiency of the unit within acceptable parameters. Which is easily done now. If one matched the total canopy recieving output in the 3 options, EW would be the leader of production & quality.
High CRI white would be option 4, which would follow EW closely in results. Now, its just about cost.
 

Shugglet

Well-Known Member
I have a test report in my thread of buds grown under white only cobs.so until you post some 23% or higher # you can use any color you like,ill stick to white only super easy and fantastic smoke.
You sure do seem to have a attitude with spectrum and this section in general lol.
Tell all these hps growers hitting 26 to 28% thc your lights work better or grow healthier plants.and lets not forget hps has a horrible spectrum
I would think genetics play a bigger role in chemical composition than light profile...
 

sixstring2112

Well-Known Member
I would think genetics play a bigger role in chemical composition than light profile...
I know this particular strain has tested at 18.5% under a 50/50 mix of hps and mh which is how i ran my op for the past 5 years before switching to cob.and none of my strains under cob plus uvb and 660nm are doing over 22% currently.so i will use it as a measurement before i listen to outdated par test and until i see one of these mixed spectrum growers pull down some spectacular looking crops i just dont buy into it.i also have experience with blurple led and the plants were decent just not what im seeing under the quantum/cob all white fixture.
A pictures worth a thousand posts around here :)
 

Hybridway

Well-Known Member
I know this particular strain has tested at 18.5% under a 50/50 mix of hps and mh which is how i ran my op for the past 5 years before switching to cob.and none of my strains under cob plus uvb and 660nm are doing over 22% currently.so i will use it as a measurement before i listen to outdated par test and until i see one of these mixed spectrum growers pull down some spectacular looking crops i just dont buy into it.i also have experience with blurple led and the plants were decent just not what im seeing under the quantum/cob all white fixture.
A pictures worth a thousand posts around here :)
I'm tryin! Lol! Just gotta get a healthy crop in. White led is enhanced hps so you're ahead of the game there, plus you got skills man.
 

captainmorgan

Well-Known Member
I know this particular strain has tested at 18.5% under a 50/50 mix of hps and mh which is how i ran my op for the past 5 years before switching to cob.and none of my strains under cob plus uvb and 660nm are doing over 22% currently.so i will use it as a measurement before i listen to outdated par test and until i see one of these mixed spectrum growers pull down some spectacular looking crops i just dont buy into it.i also have experience with blurple led and the plants were decent just not what im seeing under the quantum/cob all white fixture.
A pictures worth a thousand posts around here :)
You mean something like this, CXB3590 3500k with some added 630 nm at day 50.
 

Attachments

Randomblame

Well-Known Member
PPF messurements alone says nothing! You need at least a PAR map with real PPFD # to compare those lights.

The only reason why sellers spend only PPF values in their promotional videos is that they know their real PAR map would yield quite different results with which they can not win.
It is not important how much light is emitted in the center(for instance the 2200μMols readings at 6" of the SpectrumKing, lol!), we need to know how much light hits the entire surface.
Create a PAR map with each of these lamps and compare again.
If you were to do so, surely the Illumitex would be very far better as these tests shows.

Small 25x 40cm units can not create uniform illumination, even with lenses and reflectors. That is why we diy'ers are making our lights much bigger, so that they illuminate the surface more evenly.

Uniformity is the keyword here!

What do you think would deliver better results, a light with 1000μmols in the middle but only 50 in the corners or a lamp with 500μmols over the entire area?
Industry standards are a good thing until people(mostly sellers) starts to misinterpret them!
 

dabby duck

Well-Known Member
Kind engineers..... Here's real science..... I'm not meaning this in a negative way twords anyone in particular. Just don't want people mislead.

https://www.ncbi.nlm.nih.gov/pubmed/19246458
Interesting stuff....do you have any other links corroborating sunflower research and if sunflower morphology has ever been compared to cannabis morphology? Kind of a leap in a making a claim.....but still interesting research, no denying that.....
 

Malocan

Well-Known Member
2.6
Green light responses
The presence of a green-light photoreceptor has been in
debate for some time, but none has been discovered to date.
While there is currently no known green-specific photoreceptor,
phytochromes are able to sense green light and there is some
evidence that cryptochromes can be deactivated by green-light
(Sellaro et al,2010). Regardless of the presence or absence
of a green light sensing mechanism, there is an increasing
number of studies highlighting the effects of green light on
plants. Addition of green light has been reported to increase
plant growth rates, although whether this is due simply to
a direct effect of green light on photosynthesis (see section
three for more details) or to some other factor remains to be
seen. Interestingly, Sommer and Franke (2006) observed tha
exposing seeds of cress, radish, and carrots to bright green
laser light caused the plants to grow considerably larger. No
biological explanation for this observation has been elucidated,
but further investigation may identify some useful practical
applications. Green light is not always found to benefit plant
growth. For example, tomato seedlings are inhibited by
exposure to green light (Brazaityte et al,2010). For a detailed
review of the influence of green light on plant production see
Wang & Folta (2013).


This pdf shared @ guod long time ago

http://horticulture.ahdb.org.uk/sites/default/files/u3089/Lighting_The-principles.pdfhttp://horticulture.ahdb.org.uk/sites/default/files/u3089/Lighting_The-principles.pdf
 
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