Calling out to Weezard for LED advice

[oldmac]

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.

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.

[DreadedHermie]

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

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.

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

[MerryPrankstr]

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.

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

[Weezard]

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.

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


Weeze

[Weezard]

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

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

[MerryPrankstr]

Originally posted by Weezard

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

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

[oldmac]

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

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.

[MerryPrankstr]

Originally posted by OldMac

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

Empirical science at it's best...

MP

[Bubbleblower]

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

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.

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

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

[Weezard]

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

Say what?!:wtf:

Not lately!

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