Building a Home Made LED

[vukman]

As the capitate glands age and ripen, they turn cloudy.
The UV b and c that used to sail right through them now contributes to their rapid darkening.
The IR is also occluded and so, heats the glands, which also hastens their degradation.

LEDs produce 0 UV and almost 0 radiated IR.
I used them to confirm my theories on UV and gland ripening.

As a result of my results I now have a UV filtering roof on my greenhouse.

The thread was "Calling out to Weezard for LED advice"
By "Crunchy pants" aka "Dreaded Hermie"
Googles right up.

Damn,,,long ass read there but got through it... I see a lot of that was posted a few years back. Interesting read none the less.....

Onward and upward.....let's look toward the future of the field we like so much and see what we can do...

 

[luvdemshrooms]

pics, pics

Not quite a hex pattern and not quite done.

At 2A, the thermal pad measures 71c. 2A will give the LED's a good long lifespan, even factoring in ambient temperatures on hot days in a hot room.

It's currently running on my 100v benchtop power supply, but the components for my driver are arriving soon (inductors).

We already have a driver that we use for some of the other lights we make. A component change here and there should do nicely.

So, thanks to all of you. The many threads, with good advice and comments inspired me.

 

[rives]

The thread was "Calling out to Weezard for LED advice" By "Crunchy pants" aka "Dreaded Hermie" Googles right up.

Thanks for popping in, Weez. I've missed your input, hope you are doing well.

That said, Stardustsailor on RIU (Astir...) a diy led man with commercial aspirations, says 660 is a no-no

I've checked out his thread, and while he has an interesting theory, a couple of years of direct experience using 660's tells me that it doesn't hold up to empirical testing. Take a look at any grow done with Lumigrow fixtures - they use 660nm for the red component and work very well. SOTF420 in particular has done some great work with them.

 

[Weezard]

Tru dat!

My budding light is all 660nm., and it works a treat.


(Since peak acceptance in cannabis is 657nm., that's not at all surprising. )

My goal is lowest watts per useable photons

I use the dimmers to "tune" the red and blue emitters for maximum absorption by a particular strain.
When it's at it's most efficient, the leaves look black.
I figure, If the light is not reflected, it's absorbed.

Might save you folks some time and expense with those white leds.
If your di-chroics are balanced, there is no need for "white" light.
Tried CFLs early on, found no clear benefit.
Played with that utterly mad "martian method" hoax too, just for gits n shiggles.
Used 730 nm., narrow band, targeted, UV, and chased pond-scum, kine carotinoids around for a while.

Found that all to be a waste.

Nothing compares to a properly balanced mix of red and blue, so far.

Just my opinion, backed by many experiments.
TIOLI.

Aloha,
Weezard

 

[tenthirty]

Weezard, thanks for stopping by and for your more than valuable input.

Might save you folks some time and expense with those white leds.
If your di-chroics are balanced, there is no need for "white" light.
Tried CFLs early on, found no clear benefit.
Played with that utterly mad "martian method" hoax too, just for gits n shiggles.
Used 730 nm., narrow band, targeted, UV, and chased pond-scum, kine carotinoids around for a while.

Found that all to be a waste.

http://en.wikipedia.org/wiki/Dichroic_filter
I had to go look it up.

I use the dimmers to "tune" the red and blue emitters for maximum absorption by a particular strain.
When it's at it's most efficient, the leaves look black.
I figure, If the light is not reflected, it's absorbed.

This is an interesting observation. I like it!!!!

But???
This is somewhat of a stretch, but look at how us cavemen deal with light reflection/refraction.

http://www.dlp.com/technology/how-dlp-works/default.aspx

Well, yes if the leaf looks black, the light is being absorbed (more or less) completely.

Now I am going to assume that the plant has some sort of regulation mechanism similar to a DLP chip in operation.
So maybe you can feed the plant as much blue and red (to a point) as you can feed it,
but if the plant needs other frequencies of light in smaller quantities,
wouldn't it stand to reason, that any excess light not needed would be reflected off at any given point in time?

 

[VladTheInhaler]

Can someone please help me with nomenclature. Is this a neutral or cool white LED, it's 5000K so it's right there in the middle http://www.led1.de/shop/files/Samsung/SPHWHTL3D303E6R0K3.pdf
I really wanna get this right so I don't end up with too many cold whites.

 

[medmaker420]

Some great info in here and think the different white would be worth playing around with and or adding to the red/blue panels if anything for testing purposes.

Can't wait to see how the cw nw ww diy led panels grow buds in flower. Are there many finished grows yet to research and checkout yet?

 

[tenthirty]

Awful lot of blue and not much red, but nice broad bandwidth in the upper frequencies.
Sharp blue spike. Interesting curve.

I think that I would call these cool white.

The way they get the high efficiency from this diode is the large blue spike.
I don't know if I like this or not. In a way it's kinda cheating. ;-)

 

[tenthirty]

I've been, and many others.

Reading the threads here inspired me to try making my own light. While I'm still in the mid-stage of construction, I used all XML's. 4 CW, 4 WW and 4 NW. I bought a 10 X 10 heat sink and set the LED's in a hex pattern. I currently have them running at 1.5A while doing thermal measurements. After 24hrs, passively cooled, the LED's have only hit 56c. I intend to crank it up to 2A and see how the thermals go.

I build LED lights for a living, but this is my first grow light (power bill scared me).

Is there something in the thread you linked to that I missed?

56c seems a bit warm to me, I like to see less than 40c.

I run my XM-L's at 1750 mw. At 2A. you may be buying diodes.

 

[Weezard]

Pinin' for the fnords?

Pinin' for the fnords?

"Now I am going to assume that the plant has some sort of regulation mechanism similar to a DLP chip in operation.

Yes it does.
And it's a decent analogy.

Thylakoid cells allow the plant to adapt to different light levels.
When light is too intense, the thylakoids turn edge-on to present less surface area
This makes the leaf physically thicker.
The upper limit with sunlight is about 91k Lux
If your leaf is thick, back the light off.

So maybe you can feed the plant as much blue and red (to a point) as you can feed it,
but if the plant needs other frequencies of light in smaller quantities,

That is the IF in dispute.
I found no evidence that they need any other frequencies for vigorous, healthy, growth and maturation.


wouldn't it stand to reason, that any excess light not needed would be reflected off at any given point in time?

I think that more passes through without capture than reflects off.
And the reflection is color specific.
Most reflect green-yellow which our eyes are most sensitive to.
'cept for young leaf in the crown.
Many plants start them out reflecting red to keep them from overheating until the are full size.
Then they can handle absorbing the red so they reflect the green which is apparently too much work to up, or down convert in frequency.

Plants can and do down-convert 635nm. and shorter wavelengths, like HPS yellow.

They can also up-convert blue, but that seems more difficult for them, (shorter wavelength = higher energy), and fortunately is seldom needed.

Look into the thylakoid mechanism, it's fascinating.
The more you know, the mo' betta you grow.

Aloha,
Weeze

 

[VladTheInhaler]

Awful lot of blue and not much red, but nice broad bandwidth in the upper frequencies.
Sharp blue spike. Interesting curve.

Their warm white LED has an interesting curve: http://www.ledrise.com/files/samsung 3535 led, warmwhite, 448lm, square pcb 10x10mm.pdf
I'm thinking 15 warm whites and 10 cool whites should do the trick. I'd like to use some red but don't really want to bother with another driver. Maybe if I could find some reds that run on >1000mA.

 

[vukman]

By golly, just when ya think you might have a thing or three figured out, someone else comes to the party and tells ya you got it all wrong!!!!! ROFL....ahahah...Just joking..
Absolutely thrilled we have 'new' people's input.
I have always been a believer in the 660's but I also think that 670 and 680 play a part in things when combined with some NIR (730)..Guy name Emmerson and all that once came up with something along those lines of thinking..

We all have our own ideas and thoughts on this subject and the one thing I really appreciate about this is that we discuss instead of berating and insulting.

Wow, does this mean I'm getting mature or something?? I thought I was just a big kid playing with new toys.. Keep the thoughts and ideas coming. I owe everything I know to you all and I am grateful for it all...

 

[Weezard]

The Emerson effect gets a lot of press here, but it's much more complex than one would think.

Most experiments were done with algae and studied the enhancement of Far red by deep red under suboptimal saturation.
(There's also the Far red/Deep red, phytochrome dance that induces flowering, but that's another whole can of worms. )

What tiny, theoretical gains this indicates for Cannabis just do not justify the extra wattage required.
I have 8 plants vegging under 112 Watts of red and blue.
I will flower them with filtered sunlight.
Because it's free!

And, when you approach light saturation, there is a negative Emerson effect!

Here's a decent PDF.

http://www.google.com/url?sa=t&rct=...sg=AFQjCNHB9qg_4Mqv6AHCKx7lCEug846JkQ&cad=rja

All that said, I do use 2 chlorophyll-a, (635 and 660nm), and one chlorophyll-b source for good results.
There is little point in 2 blue sources.
Cannabis seems to use blue for phototropism as well as photosynthesis.
And I have found high blue ratios to shorten internode distance.

Much as I enjoy leaning, at the end of the day, it's about my meds.
So, I do little experiments based on my reading.
What shows promise, gets pursued.
What does not?!
Well, I may have mentioned being a lazy type.

That's why I'm lurking here.
The fact I found no value in extending the spectrum, (and the amount of power used), is certainly not definitive.
If some of us have the room to do an actual side by side experiment.
One with white added, one without.
And there turns out to be more benefit than adding an equal wattage of red and blue, I'll be all over it.
Meanwhile, I save serious money by not generating colors that the plant does not use efficiently, yah?

Aloha,
Wee, (cheap and lazy), Zard

 

[analogue]

I could do a with and without White Test.

-

I'm glad Light Saturation was mentioned



because I often wonder If I'm over doing it.

 

[tenthirty]

Weez, It looks like we are on the same page.

Plants can and do down-convert 635nm. and shorter wavelengths, like HPS yellow.

They can also up-convert blue, but that seems more difficult for them, (shorter wavelength = higher energy), and fortunately is seldom needed.

Look into the thylakoid mechanism, it's fascinating.
The more you know, the mo' betta you grow.

To down convert wavelength = basic resonance/harmonics. (big losses)

To up convert wavelength (scrub energy) = excess heat would have to be compensated for somehow.
How detrimental that is to our plant remains to be seen.
I wonder if there is a affect on VPD??
I'm going to test and see on this upcoming round.
I've got HPS, disco lights and white all in the same environment. Should be easy enough. leaf temp vs. ambient with calibrated thermometers.

The thylakoid and reaction centers/resonant rings (can we read oscillator here????) Maybe the analogy would be a VCO (voltage controlled oscillator) What is/are the control and feedback mechanism/s.
After all, isn't this section of the plant just smashing molecules together with various energies applied? (I know really crude)

Time for dinner. Yum!!

 

[tenthirty]

I could do a with and without White Test.

-

I'm glad Light Saturation was mentioned

View attachment 185640

because I often wonder If I'm over doing it.

Petflora...............

 

[vukman]

The Emerson effect gets a lot of press here, but it's much more complex than one would think.

Yes, I'm the guilty party of constantly harping about it and you have no idea how much I appreciate your input into the subject and your time you have put into researching the subject matter as well.

You do know after all is said and done, I still am going to have to test it myself.......No offence and please do not think that I am negating anything you have said.

Maybe I'm just a stubborn prick or one who lacks trust in others data...LOL. I'm almost positive I am not the only one and actually I have read over and over on other topics that no matter what people are told, they go ahead and do what they were originally going to do anyway.

<add info>..........ahhhh, a man after my own heart... I just downloaded and saved the .pdf for a little light reading in a while. I look forward to it with great anticipation........

 

[Weezard]

"After all, isn't this section of the plant just smashing molecules together with various energies applied? (I know really crude)
"

Actually, it's using light to take apart water molecules.
It releases the Oxygen and uses the Hydrogen to glue molecules together.

Google "Hill reaction in photosynthesis."

A.
W.

 

[tenthirty]

"After all, isn't this section of the plant just smashing molecules together with various energies applied? (I know really crude)
"

Actually, it's using light to take apart water molecules.
It releases the Oxygen and uses the Hydrogen to glue molecules together.

Google "Hill reaction in photosynthesis."

A.
W.

Ohhhhh! so that is what this is called. hmmmm.

This is where, at least in part I have formed some of the model in my head of how this could work.
http://plantphys.info/plant_physiology/light.shtml
http://plantphys.info/plant_biology/photopart.shtml

So i should have said molecule ripping. hehe and smashing.

After reading through the experiment notes . It kinda seem that there is a whole lot more going on.

The Hill experiment basically proves the plant makes DC or a difference in potential, and it's pretty obvious how water molecules are cracked in the lab.
Now, if the only purpose for process light was to facilitate the cracking water, it would stand to reason that this could be done with a very specific recipe of light.
Also we could assume that the light recipe would be consistent and unchanging.

In steps the The Emerson effect, and a second Emerson effect.(Thank you)
All this implies the concepts of switches, amplifiers, and most importantly, the concepts of wave theory and the diverse energies available at both the physical and quantum levels.

(I'm simplifying)
Red light makes flowers (preflowers > 18/6)
Blue light makes short internodes

Now if all that the plant was doing, was cracking water, wouldn't it stand to reason that the only thing that would happen if you changed lighting color, would be faster/slower growth.

So, I'm assuming that there is more going on behind the curtain,
and after reading many threads on led grows/experiments,
it seem to me that you can at least steer the plant (at least to some degree) with different mixes of light.
Also look at the difference, same pheno, sunlight vs. any indoor.
I'm talking growth and structure, not necessarily quality of end product.

Now, why am I even going through this drill.
For what I am doing (this is a hobby) I'm burning > 2.2kw at peak on any given day, and the op is about as small as you can get running a perpetual.
Now just through dumb luck, or other peoples good planing, the op is broken down into each phase of plant life and there are 2 instances of mommie and clone.
The whole led thing started as, "hey I can just go buy some led fixtures and save some money".
My first mistake was to start reading. ( you know where that got me.)
So, looking at the op, gee there is enough room/flexibility to do some real testing with groups and everything.
In comes the home made led and the attempt at coming up with a workable way to tune the light. (how can you tune anything if you don't have a basic understanding of how it works.)

To end this post, harvest was just completed, I have comments, observations, some stats, and some pics.

I'll post all that tomorrow, more or less.

Thank you all for stopping by and contributing.

 

[repuk]

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Thanks for the pix!

This is getting more interesting each day!

All that said, I do use 2 chlorophyll-a, (635 and 660nm), and one chlorophyll-b source for good results.
There is little point in 2 blue sources.
Cannabis seems to use blue for phototropism as well as photosynthesis.
And I have found high blue ratios to shorten internode distance.

Weezard, thanks for your posts!!! cool use for the dimmable driver while watching for the reflected color! Do you dim both reds with the same driver or have 3 dimmable drivers?

What kind of blues do you use? I assume your ratio is half power (55W) for equal power of each red (27W 635nm 27W 660nm), and the other 55W for blues? What's the surface area of your tent? what about the yields? do you completely turn off blues in the final flowering phase?? If so, why?

tenthirty wainting for those crop pics/info!

P.S. Heatsinks received, LEDs/drivers shipped yesterday.