LED and BUD QUALITY

[[Maschinenhaus]]

Interesting. I would have expected cmh to produce a bit more thc than led. Was the par same for both lighting?

For CMH-LEC, it was Adjust A Wing Hellion 315W/630W at about 4,200 Kelvin for vegetation and bloom phase.With near UV an a wide red spectrum until to 800nm. ->

For LEDs, it was Bridgelux Vero29 COB in the High CRI version at 4,000 Kelvin, no near UV and no extra red at 660nm or near ultraviolet at 730nm.

I ran the COB LEDs up to 75%, 16 of them on an area of 200x200 and I had used 90° optics made of borosilicate glass. Later I "tested" more COB, 32 pieces, with about 3,200 watts on a used area of about 12 square meters. Without lenses at 120° beam angle.

Today I am cured....

 

[delta9nxs]

i have a little experiment going on right now demonstrating the effect of intensity on morphology.

MAYBERRY (BLUE STAR S1) M-22 breeders cut

como estas ya'll! Welcome to a PPK grow of Bluestarseedco's Mayberry s1 from the Blue Star line. Blue Star = Death Star x Whitaker Blues Death Star = Sour Diesel x Sensi Star Whitaker Blues = Quimby x DJ Short 98 F4 Blueberry Josh Blue is the breeder and here is his description; "Blueberry...

www.icmag.com

the pics are not up yet there but will be soon.

i have 2 cuts of the same plant that were nearly identical at the start of the grow.

both have been grown under the same intensity defined by a single spot reading at the top dead center of each plant.

both have had the same exact spectrum at the same points in time.

5000k only for the first 2 weeks and then with 38.5 % of the bulbs changed to 2700k.

this two-week period is coming to an end monday.

same nutrient schedule and environmental conditions.

one fixture is 1680 watts and the other is 1008 watts.

the plant under 1680 is shorter, more compact, and has more shoots.

since the only difference is the overall fixture power, it looks like the overall intensity alone caused the difference.

these 2 pics were taken using the opposite horizontal pvc tube as a brace so both the distance and height are the same.

 

[Sipina]

@delta9nxs many thanks for the link!

 

[flylowgethigh]

With high power LED and soil, I have found out that 3-5 C more heat is your friend if plants can otherwise take it.

If I can turn the leaf temps up even 3*F it means a lot more light power to the plants.

The new Mars lights have removable bars that can be moved along the frame. I wonder if sliding the bars over to each side to make room for a SMH light to be mounted in the middle, parallel to the led bars, and with its own driver, would help to finish the flowers? Daisy chain into the led to get the same cycle, or run on its own timer and blast with SMH during the middle of the ‘day’ or something.

I think a hybrid light, and also add UV into the mix as another channel, is probably a better way to make an artificial environment.

 

[delta9nxs]

spot readings and par plot maps of intensity are all one-dimensional.

and do not represent the total radiation hitting the photosynthetic surfaces of the 3 dimensional plant.

i grew with bare, vertical, 1000-watt hps bulbs dropped down between plants in a checkerboard fashion for many years.

each plant basically surrounded by 4 1000-watt bulbs. this gave each plant a total of whatever radiation one 1000-watt lamp produces but broke up the application of that power 4 ways and applied it to different faces of the plant.

then came DE hps and i switched to horizontal scrog for a while. i got great yields with both styles but the vertical setup required far less labor input.

now, because LEDs are flat-faced, one-directional emitters we are back to horizontal again.

either you scrog, sog, or lose yield.

if you are a hobbyist it probably doesn't matter a great deal.

if operating expenses are fixed, constant, and expensive you have no choice but to maximize and optimize for both production and cost reduction.

it is a tight-rope, high-wire act but to stay competitive you must engage and stay on top of scientific developments and information.

a typical beam angle of grow light LEDs is 120 degrees.

that is one hell of a wide beam! i put up a crude drawing of what that angle actually is.

these flat emitters mounted to a flat bar or surface are compounding the light by overlapping in one dimension only.

looking at the plant outdoors we see that it is mostly side-lit as the earth transits under the sun.

this means varying portions of the plant are either in light or in shade but never is the whole plant illuminated evenly from all directions.

the dli maps that we see only show the cumulative results of one single point reading over the course of the day.

the sun creates an ever-changing, shifting, uneven application. very dynamic in nature.

indoors is not natural, we are tricking mother nature at every turn, every way we can, to try to grow uniform, high-grade products.

so trying to apply a high DLI just to get a high spot reading may not be the way to go.

i think the next big breakthrough in plant lighting is going to be parabolic led fixtures.

with one-dimensional fixtures, we rely on brute strength to get the depth of field.

an example of this is my 2 lights shown above.

with both lights set at 1500 umols at the top of the plant, the 1680-watt light produces 450 umols resting on the reflectix surface below each plants pot. and the 1008 watt light produces about 155 umols.

same distance from the top of the plant to the reflectix , same spot reading at the top of the plant but radically different reading 2 feet further down.

there must be an energy level, that, when applied uniformly and evenly to the whole plant from all directions in the same time span produces the same growth and yields using less total energy than a one dimensional source.

this is a 2 frequency geodesic dome. it has 40 faces and describes a hemisphere. it is icosahedron based.

every face is aimed at the center of the dome. leds mounted to these faces would compound the beam angles two ways.

one is the overlap of all the diodes on one face, and then the resultant new beam created would compound with the 39 other beam faces to create a super dense omni-directional mass of photons in the center.

it would nearly eliminate shading.

and have a profound effect on elongation.

and greatly reduce energy inputs.

 

[goingrey]

The Effect of Light Spectrum on the Morphology and Cannabinoid Content of Cannabis sativa L.

Abstract. Cannabis sativa L. flowers are the main source of Δ-9-tetrahydrocannabinol (THC) used in medicine. One of the most important growth factors in cannabis cultivation is light; light quality, light intensity, and photoperiod play a big role in a successful growth protocol. The aim of the...

www.karger.com

this deserves it's own thread.

this paper compares hps light and led light in regard to cannabis production.

the results show leds produced higher cannabinoid levels than hps.

it also explores the relationships between ratios of RGB in white light.

and the effect on both morphology and cannabinoid production.

the led lights used in this study came from the valoya co. in finland. thank you jkd for the reference to them.

valoya developed its lights while working with research institutions.

Ironically, higher cannabinoid content is actually in line with less aromatic flowers, seeing as how cannabinoids are tasteless and odorless compounds.

 

[delta9nxs]

above is a dome, which is not a true parabola but it's one way to do it.

a true parabolic arch may be better

 

[delta9nxs]

Ironically, higher cannabinoid content is actually in line with less aromatic flowers, seeing as how cannabinoids are tasteless and odorless compounds.

where did you see that in this paper? dr bugbee suggests that cannabinoid and terpene production go hand in hand as light flow increases.

do you have a reference to this?

are you saying that because cannabinoids are tasteless and odorless the more of them the less terpenes are produced?

please clarify.

 

[goingrey]

where did you see that in this paper? dr bugbee suggests that cannabinoid and terpene production go hand in hand as light flow increases.

do you have a reference to this?

are you saying that because cannabinoids are tasteless and odorless the more of them the less terpenes are produced?

please clarify.

Just my own pondering. An increase in the relative concentration of odorless compounds could result in less odor for the same amount... can't have your cake and eat it too.

 

[delta9nxs]

Just my own pondering. An increase in the relative concentration of odorless compounds would result in less odor for the same amount... can't have your cake and eat it too.

by this logic, crappy, low thc weed should smell better than potent, high thc weed.

why do they necessarily have to be mutually exclusive?

i read research papers all day, everyday when i'm not actually doing physical work.

while doing physical work i'm thinking about what i read.

i have never heard of or seen a reference to anything like this in scientific literature.

you are using "would result" as if it is a positively correct and universal conclusion, yet have no information whatsoever to back it up.

 

[goingrey]

by this logic, crappy, low thc weed should smell better than potent, high thc weed.

why do they necessarily have to be mutually exclusive?

i read research papers all day, everyday when i'm not actually doing physical work.

while doing physical work i'm thinking about what i read.

i have never heard of or seen a reference to anything like this in scientific literature.

you are using "would result" as if it is a positively correct and universal conclusion, yet have no information whatsoever to back it up.

Ok, I changed would result to could result. Take it easy man.

 

[delta9nxs]

Ok, I changed would result to could result. Take it easy man.

i am taking it easy, i'm not upset, worried, angry, or anything like that.

you are probably a great person and i would love you if i knew you. i love everybody.

perhaps the cannabinoids and terpenoids are not slices of the same pie but are two different pies.

 

[madalasatori]

Brilliant discussion chaps, kudos to all contributors very thought provoking

 

[Growenhaft]

A 400w hps will waste 30% of its power to IR heat,

why do you always think that this is a waste? narrow-minded only looking at the light. light and heat are inseparable... what matters is the heat generated by the light source... this heat generates energy in every single cell. you know that from the sun... when you go out of the dark into the sunlight and kiss your bare skin... the energy of the warmth that attaches to the light energy. light waves and heat waves... they are 2 parameters that supply living cells with energy.

plants have a special gene for this... arp6 it is anchored in the dna of every plant. it controls many mechanisms that are of enormous importance for flowering... subsequently for the success of the harvest. Incidentally, I was able to determine it myself only recently... LED makes stems without heads... they are ready... but the heads don't grow... the heat waves attached in the right proportion are missing.

annual plants, which include cannabis... overwinter as seeds. this is the only way these plants can survive... they die to be reborn. the time to start flowering is of enormous importance for you... so it is only logical that the plants have made this topic a bit more complex for themselves... only the light intensity, the right spectrum, the right duration... but also the right attached warmth of the light. this together is crucial for a complete success... without the plant being irritated by something missing.

how do we want to have the squinting only at the light intensity and duration right? lamps that deliver the best yield in terms of quantity and quality... will be those that not only deliver the greatest values on paper...but also have the right ratio of light and heat waves.

Plants that were under led and got the light and heat effects of the neighboring sodium lamp...they had heads on their stems...perfectly normal trichomes. remember... light and heat are inseparable... and obviously the warmth of the environment is not enough... it has to be heat from the light source.

 

[delta9nxs]

heat is the second most powerful regulator of plant metabolism.

this is the difference between radiant temperature and air temperature.

 

[Growenhaft]

and yet it still finds too little importance in the production of lamps... quite the opposite... the idiots want to build lamps with low heat emission... if the heat emission does not match the light intensity, this irritates the plants completely unnecessarily. many processes during flowering depend on the plant harmonizing the available measurement parameters... if there is no heat, the plant feels like it is dancing on eggshells. maybe she doesn't give everything... maybe she's expecting a cold snap... no idea what's on the girls' minds. it was noticeable that the usual stretch started much later after switching to flowering... and only hesitantly. for me it's clear... a lack of warmth in the light when switching to flowering irritates the plants more than you actually want to admit... this is where the greatest potential for all the high-tech monsters lies.

 

[[Maschinenhaus]]

What to think of this statement, so far I thought that this would be observed?

"Since plants are largely made of water, infrared radiation warms them up quickly. Water is very good at absorbing infrared radiation. Protection from infrared radiation in the greenhouse therefore has a great influence on plant temperature.

Any radiation with a wavelength of 700 nanometers (nm) or more is called infrared radiation. Above red light, therefore, the infrared range begins. In the spectrum from 700 to 2500 nm lies the near-infrared range (NIR), also called short-wave infrared radiation. Above this range, the long-wave infrared radiation begins. Since the plant does not need the infrared light for photosynthesis, it is no problem to filter out this light. This prevents excessive heating of the plant.

This heating is a result of the properties of water. Blue, green, red and short-wave near-infrared light pass through water, but infrared light from the farther spectrum, especially above 1200 nm, heats it. On a sunny day, the plants, which are after all mostly water, can heat up considerably. Then the plants and the greenhouse elements, which have also absorbed radiation, heat the air in the greenhouse. So, on such a day, the plants heat up more than the air in the greenhouse. The plant temperature will generally be higher than the greenhouse temperature.
Limits of warming

Up to a certain limit, plant warming is naturally positive. After all, the heat promotes various processes in the plant. But this is true only up to a certain limit. The combination of a lot of light, a high plant temperature and a low humidity level first leads to a standstill of photosynthesis and then to real damage. But even before this stage is reached, it can be very useful to limit the plant temperature somewhat. The evaporation process of the plants then slows down, which means that the ventilation windows need to be opened less. This keeps more CO2 in the greenhouse, which promotes growth. For some plants, such as chrysanthemums and gerberas, flower color also improves when excessive heating is prevented.

Ratio red/near infrared

Finally, the controlling effect of the ratio between the colors of light should be noted. The first part of the infrared light, between 700 and 800 nm, is the shortwave near-infrared light. This is an important part of the spectrum because the ratio between red and shortwave near-infrared light is critical to whether a plant remains compact or grows in length.

This ratio also plays a role in flower formation and the flower itself. ReduHeat filters out a small part of the short-wave near-infrared light, thereby changing the ratio. A French study shows that ReduHeat can have a beneficial effect on compactness in bedding plants. Depending on the plant species, ReduHeat ensured that the plants remained 7 to 17% shorter.

This effect was not studied in cut flowers. It could possibly be at the expense of stem length, but there are so many factors at play here that it is difficult to predict the effects. ReduHeat users have not reported any negative experiences in this area."

Reference in German

Schutz vor Infrarotstrahlung verhütet hohe Pflanzentemperaturen

Da Pflanzen größtenteils aus Wasser bestehen, werden sie durch Infrarotstrahlung schnell warm. Wasser ist nämlich sehr gut in der Lage, Infrarotstrahlung zu absorbieren. Der Schutz vor Infrarotstrahlung im Gewächshaus hat darum einen großen Einfluss auf die Pflanzentemperatur.

www.redusystems.com

 

[jahshaka]

So whats the conclusion here should i dust off the DE's or keep rolling with the sammy 301's?

 

[delta9nxs]

i gave away 49 sunlight supply AC/DE fixtures with philips greenpower lamps back in 2019 when i left oregon.

i knew i would never use them again.

these lights required me to use 225,000 btu of energy over 3500 sq ft just to offset the heat from them all.

my electric bills were huge because not only did i have the cost of operating the lights, i also had to cool the rooms.

i had 375 amps and used it all.

contrast that to the cbd room in nashville which was all led over 10k sq ft that used only 150,000 btu to cool the rooms.

we had 800 amp service but never used more than 400.

here's dr Bugbee again. this is the video that caused led manufacturers to add far-red to their lights.

everybody that sees it assumes he's talking about cannabis specifically but he is not. he is a general-purpose crop physiologist.

cannabis does need some far-red but not much.

at 21:50 in this video, he discusses the differences between energy flux and photon flux in the far-red region.

at 25:10 he talks about far-red for cannabis.

 

[YellowCanaryConsulting]

So whats the conclusion here should i dust off the DE's or keep rolling with the sammy 301's?

I had to develop my own fertilizer line to grow good led bud. My entire house now is a fertilizer test facility thanks to leds. Nute profile is the #1 factor under Leds. (as long as vpd isn't insane).


Even slow talking youtubers who don't make sense are catching on:

I found this video after Googling "buildasoil grows disgusting plants" or something like that. (What did I expect from a company that talks about microbes all day but doesn't provide PSB in their organic phosphorus booster.)

The buildasoil looks like it has too much potassium to let calphos through. My buildasoil didn't, it grew nasty tasting weed with okay yields. Consistency... Leave the cannabis shit behind if you want quality.


Which reminds me, does anyone know where I can buy SOB in the states? 5 bucks in India but they don't ship to Bidenstan.





Theory: Led is bad at sending exudates that signal normal rhizome function.

Prediction: Compost worms and all that nonsense will go out of style, and indoor organics will come with proper specialized microbes some day. None of these fertilizers on the market are growing decent bud under led. Purple stems blue leaves everywhere.