How far to keep your LED's / Quantum Boards from the canopy?

hybridway2

Amare Shill
BRB going to tape some baking paper under the QB's :D. But really would that work, or has anyone even tested different materials on LED's and how well they work in comparison? I'm now wondering what material i should get and how to attach them/it to the board (without fire hazard and how close the material should be for maximum effect). So many things are starting to make sense to me now!
After struggling for about a year under that QB I learned allot about them. They are awesome if you have the ceiling height & or evenly distributed boards.
My Diffusion test was done by accident. This cover was defective, causing a frost effect. I took it off to try to buff it out & low & behold, that section of the plant looked like it stopped growing compared to the clear lens right next to it. Leaves went yellow, all the signs of "led deficiency"/"growers error"/too high intensity even with low #'s, kicked in. The umol difference was only like 10-20umol. Was all documented but now that thread is MIA.
Even backed up that light away some more. That section of the plant was around 700ppfd. Same plant had another HLG, 96 ELITE ,320 watter on the other side. That had a reading of up to 1250 umol in many places with very little I'll effect, that didn't really kick in till the end of the plants life cycle by leaves yellowing prematurely. In retrospect, the frosted lens has put out a healthier section all along, just never realized it till then. Its funny how the clear lenses act as diffusion as well, good enough to where I was shocked & talking all about how the 96's did not give me my typical led plant problems at the time. Well, I now accredit the covers.
Clear:
Now I plan on giving each one a light wet-sand on the insides. Goal is a 50-70% frosted look.
The study I read showed 70% doing the best of the frosteds.
Greenhouse studies as we as photographer studies explaining why the object actually gets more light by means of engulfing the object (plant).
Lose 7% light output to gain up to 30% more flower, never-mind avoiding plant problems & being able to use the 1000-1500 ppf instead of 650, creating Flarf.
 

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PSUAGRO.

Well-Known Member
Pmma will discolour/ degrade over time..... Glass is where it's at, but it's at a cost & fragility.

Did you ever try running it with the covers off hybrid?
 

hybridway2

Amare Shill
Pmma will discolour/ degrade over time..... Glass is where it's at, but it's at a cost & fragility.

Did you ever try running it with the covers off hybrid?
Not entirely. I saw enough & could not afford the hit. Next run almost everything is getting some sort of diffusion & even this run will have some last minute attempts. Not sure i should this time though because its almost all SBS's. I should do it, just to both contenders.
I totally agree, glass is the bee's knees. I see growers using spaced out strips on a frying pan at low currents n watts. N,ñ&&tttr don't have the issues many post about either, when making the switch. The spread of the diodes & low wattage fixtures seam
 

ComfortCreator

Well-Known Member
You are developing a solution to "fix" the design of the HLG fixtures....they aren't broken though...

96s need to be high up. They have huge wattage power and intensity...are designed for spaces with vertical height.

Qb288s can be high up or down low. To go lower we use more boards running at a lower wattage.

More boards running at lower power allows for all the things you want. Fitting a diffuser over the 96s will use a ton of power, create tons of heat, and be inefficient.

If you are going forward regardless, ill stop commenting. Imo its a big mistake to try and use a fixture in a way it was not designed.

The fluence fixtures were designed for those that wish to run an almost perfect diffuse pattern as close as 6" away.

Trying to steer in a good direction, no offense intended.
 
You should get a light meter, you want the distance from canopy to light to be the distance that the light kind of blends together without hot spots, place the light meter equally in between the led boards or cobs or whatever leds you are using and lower the light meter and watch the reading rise and then eventually it will come to a point at which the light reading will lower, typically the distance you get the highest reading is about where you would want to be. From there you will dim the light if its needed.
 

Blossom21

Active Member
Not sure why there hasn't been mention (besides the OP) of a decent light meter.

Dr. Meter, about $30, is all you need.

Imo you are right to be curious but ask the wrong question. I would ask, what is the optimal amount of light for a plant?

Your question is tactical...how do I, vs strategic...why should I

There is an optimal spectrum and intensity for lighting. It varies based upon many factors, but the general ranges are well specified.

Now lets say you know the optimal range. Can you use it, with your setup? If your setup allowed you to be at 18" vs 12", which would you choose? Why? Now if you had to be at 12" to be optimal and it burns your plants, which is more important...max lighting or the highest quality product?

What grow method do you use? Are they growing naturally or trained? As mentioned in earlier posts, there is intensity, and there is spread.

There is no need for additional diffusers with QBs. They diffuse well especially at recommended heights.

Your friend gets no points for how close he runs his lights...only for having a great product. See my point?

Get a meter. Dont guess.
I did some research and a lux meter only catches a tiny part of the visible spectrum? But i guess it could be used as a reference if you kept your lights/setup the same each grow and knew the optimal distances beforehand. Maybe buying a real meter to measure the whole spectrum one day would be worth it in the long run. I downloaded a lux meter app in phone, i wonder how much off can that be or would it be as useful as a lux meter without having to spend money on a separate one? If i remember right i got about 40k lux readings at around 21" from the canopy with 80-85% power under one quantum board, 3000k 288pcs of lm301b's.
 
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I did some research and a lux meter only catches a tiny part of the visible spectrum? But i guess it could be used as a reference if you kept your lights/setup the same each grow and knew the optimal distances beforehand. Maybe buying a real meter to measure the whole spectrum one day would be worth it in the long run. I downloaded a lux meter app in phone, i wonder how much off can that be or would it be as useful as a lux meter without having to spend money on a separate one? If i remember right i got about 40k lux readings at around 21" from the canopy with 80-85% power under one quantum board, 3000k 288pcs of lm301b's.
You can use any light meter, you're looking for uniformity, yes par is not the same as lux but it wont matter..
 

ComfortCreator

Well-Known Member
Dr meter is $35 on Amazon. Much better than a phone. You need a decent sensor, which a phone doesnt have imo.

They are a reference...the exact spectrum and measurement are well estimated using conversion factors of 55 to 65x depending upon your spectrum...i.e. 55lux per umol at 3000k (im not looking this up, not sure that is exact).

As mentioned, it is very simple and you measure sweeping across the entire space watching the numbers change.

There are several devices we all need...a light meter is the 2nd best one i have bought. No guessing. The best part though is it is all repeatable. You use say 40k lux for something you can dial it back in exactly in your next grow.

Trust us...what you read is very important but actual experience with the device and you wont question it!
 

Blossom21

Active Member
Dr meter is $35 on Amazon. Much better than a phone. You need a decent sensor, which a phone doesnt have imo.

They are a reference...the exact spectrum and measurement are well estimated using conversion factors of 55 to 65x depending upon your spectrum...i.e. 55lux per umol at 3000k (im not looking this up, not sure that is exact).

As mentioned, it is very simple and you measure sweeping across the entire space watching the numbers change.

There are several devices we all need...a light meter is the 2nd best one i have bought. No guessing. The best part though is it is all repeatable. You use say 40k lux for something you can dial it back in exactly in your next grow.

Trust us...what you read is very important but actual experience with the device and you wont question it!
Does the quality of censor matter tho if you use the same thing every time? I'm about to buy some red strips for my next run, and i'm closer to harvest this run so it would be even more useless after that.. I think i'm just gonna keep testing myself how the plants react and not go near the danger zone anyway. If i'm gonna buy a meter i would wanna get that full spectrum, i know it's expensive but probably worth it in the long run as i keep expanding and fill my tent with with different kind of lights anyway :cool:
 

Blossom21

Active Member
Not entirely. I saw enough & could not afford the hit. Next run almost everything is getting some sort of diffusion & even this run will have some last minute attempts. Not sure i should this time though because its almost all SBS's. I should do it, just to both contenders.
I totally agree, glass is the bee's knees. I see growers using spaced out strips on a frying pan at low currents n watts. N,ñ&&tttr don't have the issues many post about either, when making the switch. The spread of the diodes & low wattage fixtures seam
Hmm ComfortCreator thinks it's not good for my quantum boards to get diffusion, sure the individual pieces aren't as close as in some DIY boards with lights stacked right next to each other etc, but would you personally recommend diffusing my boards and perhaps strips too? If i do it, i wanna do it right, or just leave them be as they are.
 

ComfortCreator

Well-Known Member
Listen, HLG aren't geniuses. Samsung is.
Samsung designed the diodes to have a 120 degree beam angle.

120 degree beam angle.
Every single diode is predesigned with a 120 degree beam angle.

Then, a board is created, understanding the beam angle in the chips. They space them and arrive at a number of chips that creates the lighting pattern they want.

Yes, some people used diffusion covers with them...for very specific applications.

But, the diffusion is built in. Any attempts to diffuse them further creates a less efficient and intense result...
 

Blossom21

Active Member
Listen, HLG aren't geniuses. Samsung is.
Samsung designed the diodes to have a 120 degree beam angle.

120 degree beam angle.
Every single diode is predesigned with a 120 degree beam angle.

Then, a board is created, understanding the beam angle in the chips. They space them and arrive at a number of chips that creates the lighting pattern they want.

Yes, some people used diffusion covers with them...for very specific applications.

But, the diffusion is built in. Any attempts to diffuse them further creates a less efficient and intense result...
Didn't Hybrid personally test them with his set and actually get better results? Or would it just work with specific LED's and how far apart they are?
 

ComfortCreator

Well-Known Member
Didn't Hybrid personally test them with his set and actually get better results? Or would it just work with specific LED's and how far apart they are?
Hey brother ive given you hard data, do with it as you will. As i suggested, dont reinvent the wheel. Engineers with degrees design the boards and do so with specific reason.

If you want more diffusion, add more boards and run them softer and closer. That is a proven success. Attempts to modify the systems would only be case specific.

If someone can prove a cover helps a qb, they would prove it. It has been done, by HLG themselves. They do not recommend it. You want the heat to dissipate from the boards.

Hybrid in his setup may find he likes his results better. I would still respectfully argue he is solving a problem the forum here could solve more efficiently. But part of the fun is doing it your own way. I am logic and science only, like Mr. Spock. When something seems illogical I will point it out.

In the end its your grow...where do you want to spend your time?
 

Growoolit

Well-Known Member
Dr meter is $35 on Amazon. Much better than a phone. You need a decent sensor, which a phone doesnt have imo.

<snipped>

Trust us...what you read is very important but actual experience with the device and you wont question it!
I'm pretty sure my plants don't understand lux and rely on PAR. That makes this particular meter less utilitarian.

I'd like a decent PAR meter, but not until after harvest at current prices.
 

ComfortCreator

Well-Known Member
I'm pretty sure my plants don't understand lux and rely on PAR. That makes this particular meter less utilitarian.

I'd like a decent PAR meter, but not until after harvest at current prices.
I highly doubt your plants know what PAR means either, I mean have they ever asked for PAR? I get your point but it is misguided.

There is a conversion formula based upon spectrum. i.e. 60lux per umol

Sure a PAR meter would be nice but if you have not gotten a lux meter yet, you are missing out on a very useful tool.

Now say you have a PAR meter does it tell you if it is too much or too little? No...it tells you a very accurate measurement you can use to measure spectrum and intensity. For most users, the PAR and lux meters will serve the same purpose.

The lux meter is very consistent. Whether or not its measurements match a PAR meter when converted...or not, it serves its purpose well. Its simply WAY more consistent than a phone, better sensor, that is all imo.
 

Growoolit

Well-Known Member
I highly doubt your plants know what PAR means either, I mean have they ever asked for PAR? I get your point but it is misguided.

There is a conversion formula based upon spectrum. i.e. 60lux per umol

Sure a PAR meter would be nice but if you have not gotten a lux meter yet, you are missing out on a very useful tool.

Now say you have a PAR meter does it tell you if it is too much or too little? No...it tells you a very accurate measurement you can use to measure spectrum and intensity. For most users, the PAR and lux meters will serve the same purpose.

The lux meter is very consistent. Whether or not its measurements match a PAR meter when converted...or not, it serves its purpose well. Its simply WAY more consistent than a phone, better sensor, that is all imo.
Semantically, I never said that my plants understand light (PAR or otherwise). I feel misrepresented by your view there.

Regardless of anthropomorphizing, I found a Youtube vid of the bloke from Migro, Sean. He calculated (graphically) some accurate conversion factors for various LEDs and other lights (where possible) to use with a free app "lux light meter by Doggo".
 

ComfortCreator

Well-Known Member
Semantically, I never said that my plants understand light (PAR or otherwise). I feel misrepresented by your view there.

Regardless of anthropomorphizing, I found a Youtube vid of the bloke from Migro, Sean. He calculated (graphically) some accurate conversion factors for various LEDs and other lights (where possible) to use with a free app "lux light meter by Doggo".
I was joking!

Your plants dont know what PAR or lux is...but i understand the difference and know what you meant....weak joke maybe.

Yes, the conversion factors are a good approximation, that was my point. Knowing the true PAR and ppfd values would be valuable to a commercial operation and a hobbyist that loves the science, but a consistent measurement is what is most important for most of us.

Really what you will focus on is not so much if its a certain number as much as you will marvel at how much it varies unless you have a very good spread of lighting. The difference between reflective surfaces and ones not very reflective is also amazing (to me). A huge difference. If you can create an even spread, intensity is just a twist of a dimmer knob. Raise and lower the lights, the change in spread is enormous...but not obvious without a meter.
 
Really what you will focus on is not so much if its a certain number as much as you will marvel at how much it varies unless you have a very good spread of lighting. The difference between reflective surfaces and ones not very reflective is also amazing (to me). A huge difference. If you can create an even spread, intensity is just a twist of a dimmer knob. Raise and lower the lights, the change in spread is enormous...but not obvious without a meter.
A lux meter will tell you how the light varies just as well as a par meter. The only advantage of a par meter would be knowing what the par values are.
 

hybridway2

Amare Shill
Hello! Id like to add that in my last post I think I mentioned diffusion csn be used both the way I suggested (for closely knit diodes or HO) OR having low wattage, more spread diodes, spread evenly through the room/tent.
I do not think HLG has tried it because I have asked. Did not get a reply on the subject though so maybe I'm wrong. Also, as Sammy may be a diode master company, I do not think they know much about how it all effects the plants. Just that they're boards sell well.
To each his own, both ways work. Just trying to help. Plenty of articles backing my claims or findings out there. I personally, want all my HO lights diffused.
Good luck!
 
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