Calling out to Weezard for LED advice

HAHAHAHAHA!

Sorry for messing up your shirt! I'm an ADD victim myself. I put my car keys down somewhere three days ago and I've yet to find them!

The only worry I have is that the graph readout for those reds says the mcd reading is 3333. A little low no? I sent the guy in china an email questioning this. I would hope they would be a little brighter?

I'm like a little kid waiting for santa right now. I can hardly contain myself. This will be a loooooonnngggg wait.

This should be REALLY interesting with this dual blue spectrum I have in both lights.

Now I just need to get some good seeds. I only have some bagseed of this jamaican stuff at the moment. Not sure what it is, but it knocks me on my ass.

I'm just setting everything up and going over the grow tent. It's a 3'x3'x6'. I would really love to have two separate places...one for veg and one for flower so that I can clone and cut some time out. However, I don't think I have the space. Maybe I can divide the grow in half by builiding a shelf to separate it? but with 5g DWC I need some headroom.....:(

Quote:

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Originally Posted by ledtime

Here is the test results of the 660nm red 1W LED's that are going into my flowering light:

http://img38.imageshack.us/img38/4903/red1wtest.jpg

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WTF?!
The wavelength looks peachy.
But in place of a lumen rating I see 3333.0 mcd.
That's 3 1/3 candela per emitter.
Now, my math stinks, but that looks like about 267 lumens for 80 leds.
I don't know a lot about 1 Watt leds. Is that typical output?

Off to do some research.
Weeze

Woops!
You are way ahead of me.
Never mind.
W.

I used an online calculator for LED's to calculate lumens per LED. The calc says 10.471 lumens per LED. There are a 100 red LED's in the array putting it at 1,047.1 lumens. That seems pretty bad????

Quote:

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Originally Posted by ledtime

I used an online calculator for LED's to calculate lumens per LED. The calc says 10.471 lumens per LED. There are a 100 red LED's in the array putting it at 1,047.1 lumens. That seems pretty bad????

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Well,


PLEASE NOTE that the lumen per watt figures in this document are lumens of light produced per watt of electricity delivered to the LED. Some LED manufacturers state much higher figures indicating the lumens per watt of radiated light. The latter, high figure is typically in the ballpark of 60-100 for red, 130-180 for orange-red, 220-265 for red-orange, 440-500 for yellow, 400-plus to near 660 for green (656 for Avago HLMP-C115), and around 50-90 for blue. The main purpose of this "high" figure is for conversion between radiometric and photometric units for the emitted light. If the conversion efficiency and the "high" lumen/watt figures are both known, multiply them to get the lumens out per watt in.
Beam brightness and width figures below are mostly ones claimed by manufacturers/distributors and I have NOT confirmed most of these.
Most Efficient Deep Red / Pure Red LEDs - 14-15 lumens/watt

InGaAlP LEDs with dominant wavelength at least 631 nm are sometimes called "royal red". These deep red InGaAlP LEDs often achieve 12-15 lumens/watt.

UPDATE 5/11/2009: LEDEngin makes some deep red high power LEDs, available at Mouser Electronics. These LEDs have rated peak wavelength of 655-670 nm, typically 660 nm. These appear to me to use GaAlAsP chemistry and to be unusually efficient for GaAlAsP.
The LEDEngin LZ4-00R210, LZ4-20R210 and LZ4-40R210, at 700 mA, are claimed to have typical voltage drop of 10.5 volts and typical radiant flux of 1.8 watts. This is typical efficiency of 24.5 percent.
One update of mine is that spectral analysis indicates dominant wavelength of 643-644 nm and luminous efficacy of the emitted light to be about 60 lumens/watt. If radiometric efficiency is indeed 24.5%, then overall luminous efficacy is 14-15 lumens per watt.
Other LEDEngin high power deep red LEDs achieve efficiency similar to or slightly lower than that of LZ4-00R210, LZ4-20R210 and LZ4-40R210. Red LEDs with GaAlAsP and Avago's similar AlGaAs in my experience, when doing well, tend to achieve 7-8 lumens per watt. But unlike the more efficient orangish red ones below, they are truly fairly pure red in color, with dominant wavelength (color specification roughly meaning hue) of 637-648 nm, usually 640-645 nm, and peak wavelength of 645-665 nm, usually 660 nm.

So, ya see, it's simple, but it's not that simple.

Your thoughts?

Weeze

I thought those LEDEngin's were a lot more efficient. With those numbers they are on par with 1W's. So these reds that I'm getting are not all that bad as they should be putting out the same lumens/watt as the 10-15W's.

Am I correct?

Quote:

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Originally Posted by ledtime

I thought those LEDEngin's were a lot more efficient. With those numbers they are on par with 1W's. So these reds that I'm getting are not all that bad as they should be putting out the same lumens/watt as the 10-15W's.

Am I correct?

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The 15 Watt dies do about 15 L. per W.
You calculate 10.471 L. per led.
(I think you meant to say per Watt, so it will be a bit less per led.)

So, no.
But you can not expect them to compete head to head.

My concern is the mcd rating.
I built an array of 10 mm. leds rated at 70,000 mcd ea.
Granted those were "hong kong" ratings and were the result of a very narrow, (15-20%), beam width.

We need to look at the output of a few other provider's 1 watt deep reds.
If these leds are in the same ballpark, pull the trigger.:rastasmoke:

What are the spec on the blue leds?

W.

It looks like the mcd rating on the blues are the same. But they are EXACTLY the same. Maybe it is a default number and they weren't testing mcd???

I guess I just have to wait until they email me back. They usually do right about now so it shouldn't be too long a wait until we get some answers!

Oh, these things are 120deg. so they say.....

What did your chinese UFO put out? 1W LED's in it right?

Quote:

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Originally Posted by ledtime

What did your chinese UFO put out? 1W LED's in it right?

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By the lux-meter?
7,500 max lux at 12" dead center.
Calibrated eyeball?
Very bright.
Results?
Vegges very well, so far.

Specs?
No gottum.:(

Gey a Reply yet?
It should be very early there.
So, we wait.

W.

So,

I finally got word just now. The red 660nm LED's put out 21.7 lumens per LED. The blue 430nm put out 13.7 lumens and the 453nm puts out 28.7 lumens.

Does that sound alright for these? The graphs he sent me before were for LED's that run at much lower wattage.

Quote:

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Originally Posted by ledtime

So,

I finally got word just now. The red 660nm LED's put out 21.7 lumens per LED. The blue 430nm put out 13.7 lumens and the 453nm puts out 28.7 lumens.

Does that sound alright for these? The graphs he sent me before were for LED's that run at much lower wattage.

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That's Peachy keen!. :thumbsup:
Especially the 660.
I think you have a winner here.
Mind if I ask what they are charging for the sample?

Yeeha!
Weeze

Haven't been followiing real close. Long division cornfuses me. But isn't 430nm in the ballpark where they start talking about radiometric power and not visible light? Or is this just a kickass blue that's still cranking out that much visible light?

Looks intriguing, either way. Good find (hopefully!) :thumbsup:

The 90W version with the custom blues was $175, and the 120W with the 660's and the custom blues was $180.

If they work then it's worth it to me for saving me the labor of putting them together!

Quote:

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Originally Posted by DreadedHermie

Haven't been followiing real close. Long division cornfuses me. But isn't 430nm in the ballpark where they start talking about radiometric power and not visible light? Or is this just a kickass blue that's still cranking out that much visible light?

Looks intriguing, either way. Good find (hopefully!) :thumbsup:

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430nm is in the violet range, just before blue. (violet 380-435nm; blue 435-500nm; uva (longwave) 320-400nm). so i guess the violet and the uva overlap a bit, hence the violet color of a blacklight?


-shake

Weezard,

I was just reading one of your posts from page 7 of this thread. Your light puts out 90k on the lux meter? That's AMAZING. The ufo only put out 7,500? That's concerning. How can I expect this 120W light that I bought to perform well at all???

Quote:

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Originally Posted by ledtime

The 90W version with the custom blues was $175, and the 120W with the 660's and the custom blues was $180.

If they work then it's worth it to me for saving me the labor of putting them together!

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Outstanding! I can't build them for less.

W.

Quote:

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Originally Posted by ledtime

Weezard,

I was just reading one of your posts from page 7 of this thread. Your light puts out 90k on the lux meter? That's AMAZING. The ufo only put out 7,500? That's concerning. How can I expect this 120W light that I bought to perform well at all???

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Relax, brah that reading is not impressive when you hold the sensor a few centimeters from the emitter.
At normal growing heights, I run 12K to 75K
91k. lux is just where photosynthesis halts.
That's why you can stop the stretch with a procyon.
What you are actually doing is stopping growth with light saturation.
Changing the R:B without saturation of either color is what give real control of the internode distance
Works well with little girls, not so well with big mommas.
Large plants only stop growing at the top.
Ongoing bottom growth will shove the tops right up agaist the light and then they bleach and will burn with the big emitters.
I built my light with too much red at max so that I could tweak the R:B by turning just the red down.
Look how fast light drops with distance from the source;
[attachment=o219059]

[attachment=o219060]
If your guy isn't just making up specs, your light will be more than adequate and, perhaps, stellar.

"Patient tends to ramble":D
Weeze

This wait is tough. They said the lights will ship out June 2nd.

Quote:

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Originally Posted by ledtime

This wait is tough. They said the lights will ship out June 2nd.

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Dat frikken slow boat from China always toasts my Taco.

Buck-up me Buck-o, this is the hardest part.
Watchin' dem little girls grow up to be, Lovely Ladies of the Light,
is worth da hassle, and will warm your heart.
I May be wrong, but I'm prolly right.

Building one's own energy input is great fun!
Learning is mentally and emotionally rewarding as well.
But.
Growing is addictive!:jointsmile:

I had to stop naming da girls.

Da sorrow of parting was not all sweet.

Damn I miss Virginia!
[attachment=o219159]
Though she does live on as part of my personal neuro-chemistry!:jointsmile:

Dis be a good time to read every thing you can find about growing.
"All grows are only as good as their weakest link."

With timers, LEDs and DWC,
the weakest link is probably, me.
I automate as best I can.
To mitigate my attention span.

It can get nanometer short, brah!:jointsmile:
My best advice?
Read bruddah, read.:thumbsup:

Aloha nui
Wee Zard

I've been reading non-stop. It seems that is all that I'm doing in my free time. I've learned a lot however and that is always nice.

The china men are shipping it 3 day DHL delivery so it should be here by friday.

Hey, can you recommend a good place to get good seeds?

This morning I was able to have another conversation with the manufacturer. This place holds the original patent to the UFO LED light.

I was explaining to him how others have seen the current draw around .31 rather than the .75 that it was supposed to be.

He said that other facilities in china are selling these lamps using .5W LED's and advertising them at 1W. To the eye they look the same, but when you put them under testing equiptment the results tell the real story.

He is currently working on 3W and 5W versions. So later this year I may have another light to fiddle with if I don't build a custom one. We'll see. These lights coming should be nice though! :jointsmile:

hello...
have been lurking about for a while now or as i like to call it...getting a free education.
if i start naming names...i will surely leave someone out so...
thanks to all, quite a read so far...

have decided to join your led party if i may, i love a project with a happy ending.

playing with ledeng 5 watt leds (from mouser so unknown bins).
660nm red, 465nm blue and warm white.
except for the soldering (really great heat sink, needs massive soldering iron)

trying to grow inside 5 gallon white buckets,
leds mounted on lid, 1 plant inside each white bucket.
leds glued to computer cpu fan/heatsinks. (cheap and very reliable)
1 bucket with 4-5W reds and 1-5W blue, 14.6 volts @ 1Amp.
1 bucket with 4-5W reds and 4-5W warm whites, 24.4 volts @ 1Amp.

last night, the red/warm white combo toasted a plant like in an oven...
didn't even have time to say goodbye....
it is time to pulse(pwm) them for brightness adjustments.

brain pick time..........

Q. am designing a fixed current source for pwm...
would i design the current max to be the 5W led pulsed max 2 amps?
( the pwm could then pulse about 2 amps for max uE....right?)

am not sure of what the voltage will do when the current is switched off by pwm.
cannot exceed led voltage specs by too much.

the voice of experience says.....
higher than max led voltage very very bad...will not love you long time.

i stole this pdf somewhere (if from one of you...oops...sorry) and as i read,
it mentions that plants can be pulsed. since it is so easy to pwm...i like their way,
but is it right? need some forum brain trust action.

"The light utilization efficiency and relative photon requirement of photosynthesis in pulsed and continuous light from light emitting diodes (LEDs) has been measured.
First, we characterized the photon requirement of photosynthesis from light of LEDs that differ in spectral quality.
A photon requirement of 10.3 f 0.4 was measured using light
from a 658 nm peak wavelength (22 nm half band width) LED over the range of 0-50 pmol photons m-2 s-'
in 2 kPa 0 2 in leaves of tomato (Lycopersicon esculentum Mill., cv. VF36).
Because the conversion of electrical power to photons increased with wavelength, LED lamps with peak photon output of 668 nm were most efficient for converting electricity to photo synthetically fixed carbon. The effect of pulsed irradiation on photosynthesis was then measured.
When all of the light to make the equivalent of 50 pmol photons mp2 s-' was provided during 1.5 ps pulses of 5000 pmol photons mP2 s-' followed by 148.5 ps dark periods, photosynthesis was the same as in continuous 50 pmol photons mP2 s-'.
When the pulse light and dark periods were lengthened to 200 ps and 19.8 ms, respectively, photosynthesis was reduced, although the averaged photon flux density was unchanged.
Under these conditions, the light pulses delivered 1017 photons mP2, which we calculate to be equivalent to the capacitance of PS I or PS 11.
Data support the theory that photons in pulses of 100 ps or shorter are absorbed and stored in the reaction centers to be used in electron transport during the dark period.
When lightldark pulses were lengthened to 2 ms light and 198 ms dark, net photosynthesis was reduced to half of that measured in continuous light.
Pigments of the xanthophyll cycle were not affected by any of these pulsed light treatments even though zeaxanthin formation occurred when leaves were forced to dissipate an equal amount of continuous light."
thanks to: Daniel J. Tennessen Raymond J. Bulba Thomas D. Sharkey 1994 u of wisconsin
link to whole pdf: https://mywebspace.wisc.edu/tsharkey...ght%201995.pdf
sorry kind of long....perhaps somebody can translate......

148.5uSec/1.5uSec = 99 that should save some energy...............
but will need 100 times the number of photons for that 1.5uSec.
would not be surprised if it evens out in the end.

Q. any ideas on what frequency i should run the pwm?
according to dan, ray and tom above, it appears to matter........
(150uSec = 6666Hz ??? not sure what 150ps is and what the heck is a pmol does p equal u ???)

Q. anyone have any way to convert from led output to uE's???

i have been mistreating electrons since vacuum tubes,
so if anyone needs any help in the designing
or the killing of electronic type thingys you but have to ask.

i do go on and on.....
but a toke or two helps the juices flow,
this is not so simple a subject!!!

thanks for all your help...
19toker45

Inside every older man is a younger man,
wondering what the hell happened!!!

Sounds like you'll feel right at home here.
Been hoping someone would volunteer to try pulsing.
Oh, psec is pico-second
Prolly pico-mole as well.

What's the verdict on the warm/white leds so far?

Aloha,
Weezard

Weez,

Here is a link to the pictures of the test results from the actual LED's that went into my lamps. The files are named according to wavelength.

Pictures by ledtime1 - Photobucket :thumbsup:

Hello 19toker45,

That scientific paper was originally posted by Physicsnole, and is one of my favorites. It was the first paper I'd seen where they used LEDs to try and see what wavelength of light worked for photosynethsis rather then use another light source and filters. Keep in mind that paper is at least 14 years old tho. I really wish someone would come up with some newer research papers for us to work from. And of course, the pulsing idea holds some potential, but how to realize it seems hard to figure.

I was told by an engineer, who helped me with my first DIY light power supply, to always use a dimmer in the AC side feeding the power supply. The output of the dimmer is a square wave and is more efficent at turning the diodes on/off then a regular sine wave.

If I was going to pursue pulsing diodes, that is where I'd start.
(I hope igrowwithmatches reads this also)

Welcome to the mind warp known as LEDs.

Quote:

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i love a project with a happy ending

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Happy ending cost $50 extra. You #1 G.I.! :thumbsup:

Quote:

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trying to grow inside 5 gallon white buckets,
last night, the red/warm white combo toasted a plant like in an oven...

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You need ventilation, which you don't mention. Got any?

White buckets may present problems for lotsa reasons, especially if you're gonna try to flower in them. (Nothing insurmountable, though.) How'd you decide on growing in them?

Quote:

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....perhaps somebody can translate......"50 pmol photons mp2 s-' was provided during 1.5 ps pulses of 5000 pmol photons mP2 s-' followed by 148.5 ps dark periods"

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As Weezard pointed out, a ps is a pico-second. A trillionth of a second. Equipment that can pulse at that resolution isn't exactly available at Radio Shack....

Quote:

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148.5uSec/1.5uSec = 99 that should save some energy...............
but will need 100 times the number of photons for that 1.5uSec.

150uSec = 6666Hz ???

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Okay, here's a "small" :D problem: you substitued microseconds (a millionth of a second) for picoseconds. Subsequent calculations will be off by a factor of one million. :( (I know: picky, picky....)

Google "pulse width modulation" for more detail. It works great for dimming.
You only need to "pulse" faster than about 250Hz so your eyes can't detect it. Typical rates in PWM dimming range from 1,000Hz to 200,000Hz (cycles per second, for the onlookers), which is many orders of magnitude slower that those trillionths of seconds Sharkey et al. were dealing with.

Two way different animals. Sorry, you're not going to get "pulsing," as the term is bandied about here, out of a PWM dimmer. Hope this saves you some aggravation. :thumbsup:

Weezard,

I have a pic here. I'm in the process of setting things up and figured you'd like to see....

http://i735.photobucket.com/albums/w...1/IMG00030.jpg

It's brighter than bright. When I turned on the flowering light, without looking at the bulbs, just the light in the room I saw green when the light turned off.

It filled an entire 10' x 12' room with all red! We'll see how it does. Wish I had a lux meter to let you know.

can't wait to hear/see the results ledtime!

looks good.


-shake

So I wanted to see how good this blue veg light works. My wife has been growing fresh herbs outside and her stevia plant was looking VERY sad.

So yesterday I took it and put it under the blue light and this thing perked right up in about 25 mins. The leaves weren't wilted and droopy anymore!

It must be doing something right. Can't wait to see what it does with other things!

are you gonna do a grow log ledtime?

i hope that you consider it!


-shake

Quote:

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Originally Posted by DreadedHermie

Two way different animals. Sorry, you're not going to get "pulsing," as the term is bandied about here, out of a PWM dimmer. Hope this saves you some aggravation.

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Hermie,

I did not mean to give the impression you could get "pulsing" from a dimmer, but that a dimmer produces a square wave that is more efficent to the diodes then a sine wave.

It is a starting point in understaning the pulsing concept tho, rectify the output, double the amplitude of the remainder and you effectively have the same power with 1/2 the time being on and 1/2 the time off.

As to the frequency that this pulsing must occur, it probably doesn't matter, we are not trying to fool the human eye just get photons to the plant. What might be more improtant is the ratio of the on and off, but it is going to depend a lot on thermal management, which brings me back to the point of that being an old paper. They where useing 5mm diodes back then, we are up to some serious hi power LEDs now, so the thermal dynamic issues to pull off pulsing is now much different.

Remember there is no "free lunch" here if you get x number of photons per watt (or mili or micro), per second (or mico or nano) and you want the same number of photons in the same time but some off time then power must increase. The proposed pulsing theroy is seeking to increase efficent use of electron conversion to photon energy for plant use, and much study remains to see how much could really be gained.

Quote:

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I did not mean to give the impression you could get "pulsing" from a dimmer

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You didn't. Everything you said is gold, IMO. As someone wrote on this board, "Your words have iron."

Two days went by and 19toker45's question about frying his plants went unanswered, so I just jumped in. I'd really like to hear more about his setup, hope he posts again.

The pulsing / PWM thing (as presented by 19toker45) looked like it was gonna get people confused. I'm a firm believer in making this stuff seem more accessible. That's what I like so much about your style, and Weezard's. Anybuddy can cut and paste complicated stuff. You guys understand it well enough to express it in different (less technical) terminology. You can restate the concepts in your own words, which is a common metric for comprehension.

Teaching, IMO, is not about how "smart" you are. It's about how clear you can make ideas (which does have to do with how smart you are!)

I'm sure 19toker understands rectifying AC and is familiar with various waveforms (audio amps = o-scope). But not everybody following this thread does, and, happily, it's not necessary for building an effective light with dimming capability. With the equipment available to me, pulsing @ 1.5 ps might as well be just a theoretical concept-- interesting to consider, but not within my power to pull off. Kinda like the particle accelerator I'm building in the garage. :D

PWM dimming, though, we can ALL take advantage of. It'd be a shame if folks discounted PWM because they ran into a brick wall with "pico-pulsing."

:greenthumb: Yo' admirer always, Hermie

Quote:

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Originally Posted by OldMac
As to the frequency that this pulsing must occur, it probably doesn't matter, we are not trying to fool the human eye just get photons to the plant. What might be more improtant is the ratio of the on and off, but it is going to depend a lot on thermal management, which brings me back to the point of that being an old paper. They where useing 5mm diodes back then, we are up to some serious hi power LEDs now, so the thermal dynamic issues to pull off pulsing is now much different.

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You are quite right, OldMac.

I measured my TI Probloom with my newly acquired LUX meter.
At "Ground Zero" it measure Over Scale (400,000 LUX)
At 1 1/2 inches it's 396K LUX.

I'm gonna do a much more in-depth measurement when I can set up a rig that makes it easier to tak the measurements and then publish the results along with measuements on the output of the procyon. I'm also curious as to what the level was in my grow room so I'll publish those as well.

Later,
MP

Quote:

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Originally Posted by ledtime

Weezard,

I have a pic here. I'm in the process of setting things up and figured you'd like to see....

http://i735.photobucket.com/albums/w...1/IMG00030.jpg

It's brighter than bright. When I turned on the flowering light, without looking at the bulbs, just the light in the room I saw green when the light turned off.

It filled an entire 10' x 12' room with all red! We'll see how it does. Wish I had a lux meter to let you know.

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You have scored!.:thumbsup:
This is getting very interesting!


Weeze

Quote:

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Originally Posted by MerryPrankstr

You are quite right, OldMac.

I measured my TI Probloom with my newly acquired LUX meter.
At "Ground Zero" it measure Over Scale (400,000 LUX)
At 1 1/2 inches it's 396K LUX.

I'm gonna do a much more in-depth measurement when I can set up a rig that makes it easier to tak the measurements and then publish the results along with measuements on the output of the procyon. I'm also curious as to what the level was in my grow room so I'll publish those as well.

Later,
MP

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Brilliant, MP!

It's all relative, of course but. for comparing lights of the same wavelength it should be a usable comparative.
I have read the 91k lux of sunlight will halt photosynthesis.
How that translates to 660 nm, etc. I have almost no idea.
Seems we are about to find out.:):thumbsup:

ciao 4 now

Weeze

Originally posted by Weezard

Quote:

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It's all relative, of course but. for comparing lights of the same wavelength it should be a usable comparative.

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Absolutely.

Since the two lights have different blends of frequencies no direct comparison was intended. I was thinking more of a table of LUX output for each type as a guide for placement.

Hopefully start some time this week.
Take care weez...
MP

Quote:

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Originally Posted by MerryPrankstr

I'm gonna do a much more in-depth measurement when I can set up a rig that makes it easier to tak the measurements and then publish the results along with measuements on the output of the procyon. I'm also curious as to what the level was in my grow room so I'll publish those as well.

Later,
MP

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Hey MP, I'm really looking forward to your measurements.
Ahhhh, scientific curiousity is a wonderfull thing. (plus stuff like this keeps the engineers at bay; no saying "...well THERORETICALLY it should do..." or my favorite"...according to the book...."

Do something, use something, then measure and see for yourself.

Originally posted by OldMac

Quote:

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Do something, use something, then measure and see for yourself.

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Empirical science at it's best...

MP

Quote:

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Originally Posted by Weezard

Also read them a study on the effects of UVb on complex organic compounds.

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After reading a few studies as well I decided to jump on the UVB broadbandwagon.
Wether the THC story is true or not I don't know. If you add a UV light and get more THC that doesn't mean the UV in the light is responsible for that and I haven't found any convincing proof UVB will increase THC. But for sure UVB does great things for flowers and fruits or even lettuce and missing it in the spectrum might be one of the main reasons why indoor weed is never as good as outdoor.

Quote:

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Originally Posted by Weezard

What you are actually doing is stopping growth with light saturation.

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That's what I need to know, what is the maximum saturation for a canopy.
I did google that of course and ended up here :)

"might be one of the main reasons why indoor weed is never as good as outdoor. "

Say what?!:wtf:

Not lately!:D

I have clones indoors and out
The indoor girls are keeping pace with the outdoor girls for size and health.
It may be hard to quantify potency, but first tests put the outdoor buds to shame.
I'm picking UVb as the most probable 'cause and rain as a factor.
I will eliminate the rain effect with my next test and am considering a window glass shelter, (mini-greenhouse), outdoors to stop rain and UVb.

Old Mac has offered to turn his Vitamin B. off for a run and will present the results of his bio assay in a few months.

My preliminary, (no UV.), results are making me very happy.
The potency of the indoor buds is amazing.:stoned:

As for light saturation.
91K lux, (of solar spectrum), is about max. I'm guessing it's a bit less for LEDs because of the higher absorbtion and the lower sensitivity of the meter at those wavelengths.

Just my 2 cent, but I think we're on to something.

Aloha,
Weezard