IF you are new to LED and want help choosing what to buy, POST HERE!

stardustsailor said:

Old news ....
The topic this "Beta test team " has "researched" ,
we 've already " been through " ,say a whole year ago , before them .
Again: OLD NEWS .
In this forum ,we're always ahead of everyone else ,regarding growing mj with solid state lights.
All the rest ,either they copy our work ,or either they are simply far " behind " us ..
" They are still on the way to it ,when we've already returned from it . "

https://www.rollitup.org/t/what-kind-of-light-mj-likes-decoded-from-its-reflectance.658111/

https://www.rollitup.org/t/photosynthesis-under-solid-state-light-setting-the-standards.833449/


Cheers.

Click to expand...

I'm glad I posted those. This is the reason it's great to be wrong sometimes, learning time.

Stardustsailor, what is the best version of this chart in your opinion? I've found a number of posts showing the RQE GG707 posted as being outdated as well (left side [<400nm] incorrect due to instrument issues for the test that resulted in the RQE.) I'm looking for one that gets the thumbs up for being as close to 100% accurate as possible, I doubt that is the RQE, but it's an obvious big step up from what I had been using. I'm guessing the one I posted from icemag is closer than the RQE, but would like to hear your opinion as you have obviously dug deep into this.

The best version of that chart should be made a sticky, that is the basis of lighting design and should be the first thing anyone looks at before designing a system. (especially with the ones I was originally using/posted being more well known than the updated versions.)

Some reading for you...no specific order.

http://hortsci.ashspublications.org/content/28/12/1197.full.pdf
http://biology.mcgill.ca/Phytotron/LightWkshp1994/1.5 Bugbee/Bugbee text.htm
http://www.gavita-holland.com/index.php/item/lumens-are-for-humans.html
http://www.eyehortilux.com/education-room/grow-guide.aspx
http://growershouse.com/images/PDFs/BUGBEEpub__6441190.pdf
http://www.valoya.com/plants-light
http://www.life.illinois.edu/govindjee/photosynBook/Chapter11.pdf
http://vertical-farmers.com/Illumitex_Horticulture.pdf
http://chameleongrowsystems.com/Chameleon_Grow_Systems/Relative_Quantum_Efficiency.html

Greengenes707 said:

Some reading for you...no specific order.

http://hortsci.ashspublications.org/content/28/12/1197.full.pdf
http://biology.mcgill.ca/Phytotron/LightWkshp1994/1.5 Bugbee/Bugbee text.htm
http://www.gavita-holland.com/index.php/item/lumens-are-for-humans.html
http://www.eyehortilux.com/education-room/grow-guide.aspx
http://growershouse.com/images/PDFs/BUGBEEpub__6441190.pdf
http://www.valoya.com/plants-light
http://www.life.illinois.edu/govindjee/photosynBook/Chapter11.pdf
http://vertical-farmers.com/Illumitex_Horticulture.pdf
http://chameleongrowsystems.com/Chameleon_Grow_Systems/Relative_Quantum_Efficiency.html

Click to expand...

The first one you link to goes directly to my question. Read the first paragraph.

"Abstract.
Photosynthesis is fundamentally driven by photon flux rather than energy flux,
but not all absorbed photons yield equal amounts of photosynthesis. Thus, two measures
of photosynthetically active radiation have emerged: photosynthetic photon flux (PPF),
which values all photons from 400 to 700 nm equally, and yield photon flux (YPF), which
weights photons in the range from 360 to 760 nm according to plant photosynthetic
response. We selected seven common radiation sources and measured YPF and PPF from
each source with a spectroradiometer."

Note they tell you right away that the measurements are only accurate between 400 and 700 or 360nm and 760nm.

I won't bother reading the ones by companies selling lights, but I will take a look through the rest.

nomofatum said:

The first one you link to goes directly to my question. Read the first paragraph.

"Abstract.
Photosynthesis is fundamentally driven by photon flux rather than energy flux,
but not all absorbed photons yield equal amounts of photosynthesis. Thus, two measures
of photosynthetically active radiation have emerged: photosynthetic photon flux (PPF),
which values all photons from 400 to 700 nm equally, and yield photon flux (YPF), which
weights photons in the range from 360 to 760 nm according to plant photosynthetic
response. We selected seven common radiation sources and measured YPF and PPF from
each source with a spectroradiometer."

Note they tell you right away that the measurements are only accurate between 400 and 700 or 360nm and 760nm.

I won't bother reading the ones by companies selling lights, but I will take a look through the rest.

Click to expand...

You are wrong. I will explain in depth when I get home to a full keyboard.
Read all the links...they are all important...and all by the most major of actual horticulture brands...used by the most prestigious in any industry.
By not reading them you are doing exactly what you claim to be here preventing...keeping. All options on the table...each has its benefits.

Keep reading and maybe you will understand...I thought you had a high IQ

PPF is the par readings...all photons counted equally.
YPF is a product of the intensity of each nm in the spectrum being output, and the RQE values(in the chameleon link). YPF is like lumens for plants.

It's so hard to be nice about this

nomofatum said:

GG is so silly. You summarized what I quoted. After reading the rest they only confirm the first. The RQE is correct in the middle, but the left side is fucked and needs updating. Though I guess you could just ignore UVA/UVB, but stardust's thread didn't even though the RQE says we should.

Also I know a few very senior members who will come in here and bitch slap you if you say deep blues aren't used.

Looks like the guys at Ice Mag actually got this one right and one upped RIU this time.

Click to expand...

No updating needed...blue is simply not as effcieny at photosynthesis.
Please show evidence of anything you say. RQE is correct and you have yet to show anything at all to show otherwise.

And I don't think you understand that YPF changes spectrum to spectrum. It is no a universal anything...just a description of the photosynthetic effciency of that specific spectrum.
The RQE is the universal aspect.

So please support and show evidence of your claims. I really don't need o do this. It was not I or RIU that came up with RQE...it is validated/supported/used by every real professional and academical facility/institution.

And if you actually read the links...specially the chameleon one...you would see the actual values of the RQE, not a general graph. And all the way from 400nm-500nmall have the same RQE...~.7...or 70%. So what wee you think...none of us have said deep blue is useless.
The hard data values also shows that UVA has value

Keep trying

Greengenes707 said:

No updating needed...blue is simply not as effcieny at photosynthesis.
Please show evidence of anything you say. RQE is correct and you have yet to show anything at all to show otherwise.

And I don't think you understand that YPF changes spectrum to spectrum. It is no a universal anything...just a description of the photosynthetic effciency of that specific spectrum.
The RQE is the universal aspect.

So please support and show evidence of your claims. I really don't need o do this. It was not I or RIU that came up with RQE...it is validated/supported/used by every real professional and academical facility/institution.

And if you actually read the links...specially the chameleon one...you would see the actual values of the RQE, not a general graph. And all the way from 400nm-500nmall have the same RQE...~.7...or 70%. So what wee you think...none of us have said deep blue is useless.
The hard data values also shows that UVA has value

Keep trying

Click to expand...

"Abstract.
Photosynthesis is fundamentally driven by photon flux rather than energy flux,
but not all absorbed photons yield equal amounts of photosynthesis. Thus, two measures
of photosynthetically active radiation have emerged: photosynthetic photon flux (PPF),
which values all photons from 400 to 700 nm equally, and yield photon flux (YPF), which
weights photons in the range from 360 to 760 nm according to plant photosynthetic
response. We selected seven common radiation sources and measured YPF and PPF from
each source with a spectroradiometer."

You can find statements to this effect in other links you provided. The PPF and YPF measurments don't even measure most of UVA and UVB.

UVA = 315nm-400nm
UVB = 280-315nm

According to the RQE the UVB is worthless and only the top end of the UVA range has value. But the measurements are limited to only include the top end of the UVA range. If you look at the ice mag thread you will see all the evidence you need. Based on their testing with better instruments the plants continue to absorb at >80% all the way down to UVB and into UVC at least.

You guys already proved I was working off old wrong data, I'm just looking for the best available current version and the RQE isn't it.

My post was removed? Was calling you silly an attack or something? I wouldn't think so. I was just pointing out that your reponse was simply a summary of what I had already quoted (without the wavelength limitations of both of those measures.)

nomofatum said:

"Abstract.
Photosynthesis is fundamentally driven by photon flux rather than energy flux,
but not all absorbed photons yield equal amounts of photosynthesis. Thus, two measures
of photosynthetically active radiation have emerged: photosynthetic photon flux (PPF),
which values all photons from 400 to 700 nm equally, and yield photon flux (YPF), which
weights photons in the range from 360 to 760 nm according to plant photosynthetic
response. We selected seven common radiation sources and measured YPF and PPF from
each source with a spectroradiometer."

UVA = 315nm-400nm
UVB = 280-315nm

According to the RQE the UVB is worthless and only the top end of the UVA range has value. But the measurements are limited to only include the top end of the UVA range. If you look at the ice mag thread you will see all the evidence you need. Based on their testing with better instruments the plants continue to absorb at >80% all the way down to UVB and into UVC at least.

Click to expand...

Links and citations of scientific evidence is a great a great way to show things fyi

Greengenes707 said:

Links and citations of scientific evidence is a great a great way to show things fyi

Click to expand...

I can quote your own link if you can't find it, lol

In any event based on what your links + the ice mag thread and google results I'm just going to go forward with the assumption that 280nm-700nm is all >80% usable. Tanning + 3000k + 6500k + something green should give me what I'm looking for. The CMH that I'm going to mix with my LEDs will cover green range, but maybe not to the level I could. Next grow will likely get some green range LEDs added.

Lurker's first post. Seems like the discussion of this thread has evolved from its original purpose, but I thought I'd give it a shot.

I'm rather in awe of several of the contributors here and the rigs they've built.

I need help choosing, buying or building a good led light. Grow area is 46″ wide x 30″ deep x 78″ tall, so ~9.58 sq ft. Grow method is organic living soil in smart pots. Number of plants for the area is probably better at 2, but I've done 4 in the past. Currently grow with T5 for veg and an old, crappy no-name LED panel. The only stats I have for the current are the following:

• LED Qty: 120 pcs
• Wattage: 120*3W
• LED Type: 3W Single Chip
• Spectrum: Custom 410nm - 850nm
• Input Voltage: AC85~264V
• Output Voltage: DC32~45V
• LUX: 33000lux/1m
  18500/1.5m

Results over the past few years have been fair.

Intrigued by the CRX3070 and other COBs, but have minimal DIY skills. (I've built computers, but that's pretty much plug and play.)

Controlling heat, and therefore efficiency, is my chief concern.

Recommendations?

dark76 said:

Controlling heat, and therefore efficiency, is my chief concern.

Recommendations?

Click to expand...

Water Cooling + Latest Cree COB if your chief concern is really efficiency. DIY can be very simple if you make the right choices. You need to be able to solder (basic soldering is fine, we aren't talking any tiny circuits here.) You need to be able to keep the + and - on the DC side straight. You need to be able to glue, screw, and drill. If you can do that you can build any decent DIY LED setup.

Note that there are a number of less efficient and much cheaper LED options however. It will take some time for the most efficient (Cree COBs) option to pay off over the vero or epistar options.

I'm waiting on my pump for my watercooling setup. Once it arrives I will post pics of the setup. It's just using a copper 1/4 inch water line thermal adhesived to a piece of angle aluminum. The COBs are also thermal adhesived to the opposite side of the angle aluminum. A pump will circulate the water out of my room into my garage and into a small car radiator. (big enough to not need any fans, just 1 12w water pump for 1200w of LEDs.)

dark76 said:

Lurker's first post. Seems like the discussion of this thread has evolved from its original purpose, but I thought I'd give it a shot.

I'm rather in awe of several of the contributors here and the rigs they've built.

I need help choosing, buying or building a good led light. Grow area is 46″ wide x 30″ deep x 78″ tall, so ~9.58 sq ft. Grow method is organic living soil in smart pots. Number of plants for the area is probably better at 2, but I've done 4 in the past. Currently grow with T5 for veg and an old, crappy no-name LED panel. The only stats I have for the current are the following:

• LED Qty: 120 pcs
• Wattage: 120*3W
• LED Type: 3W Single Chip
• Spectrum: Custom 410nm - 850nm
• Input Voltage: AC85~264V
• Output Voltage: DC32~45V
• LUX: 33000lux/1m
  18500/1.5m

Results over the past few years have been fair.

Intrigued by the CRX3070 and other COBs, but have minimal DIY skills. (I've built computers, but that's pretty much plug and play.)

Controlling heat, and therefore efficiency, is my chief concern.

Recommendations?

Click to expand...

Vero and CREE COBs can be built with no soldering or drilling and will give you great efficiency plus the ability to run them at many different amps/volts and thus give you some choices in the efficiency vs power balancing act. Running multiple smaller COBs will help with the heat problem too but only if you're using integrated arrays and not those, IMHO, waste of time multi-chip arrays that get called COBs. Look around the LED forum for all the COB threads for some examples. Good Luck!

Thanks for the replies. I've been leaning Gaius's Ganjatica. I like the idea of a mult-use panel so I can retire the T5s. Gaius apparently built that light for a 4'x3' (12 sq ft) space, but it sure looks a lot bigger than my area from his photos.

I've been searching for a thread outlining the steps to determine how much I'd need for my area, that is scale his build down a bit. I know SupraSPL recommends 25-30 watts/sq ft, but I'm getting lost with all the talk about running the lights soft and how that affects things, etc.

Is there a collection of formulae I should be using when selecting the COBs, Drivers, etc? I seem to recall seeing one before, but I may be mistaken.

dark76 said:

Thanks for the replies. I've been leaning Gaius's Ganjatica. I like the idea of a mult-use panel so I can retire the T5s. Gaius apparently built that light for a 4'x3' (12 sq ft) space, but it sure looks a lot bigger than my area from his photos.

I've been searching for a thread outlining the steps to determine how much I'd need for my area, that is scale his build down a bit. I know SupraSPL recommends 25-30 watts/sq ft, but I'm getting lost with all the talk about running the lights soft and how that affects things, etc.

Is there a collection of formulae I should be using when selecting the COBs, Drivers, etc? I seem to recall seeing one before, but I may be mistaken.

Click to expand...

25-30w would be less light per sqft than the average grow room on here(not including. A little more than 40w per sqft of the CXA3070 would put out light about equivalent to the average system (600w HPS 4x4 space.) I would look at 40-60w sqft. 25-30w may get the highest grams per watt, but you will get less grams from your space at that light level.

Use a light measurement as your benchmark. I have been paying most attention to lumens, from all the systems I've seen on here the average is about 5500lm/sqft. I found a professional lighting recommendation of 7500lm/sqft as ideal. Now lumens get skewed by what color light you are looking at, but the skew shouldn't be that bad since we are comparing warm colors to warm colors (warm white cxa3070 and HPS.) You can look for a PAR watt target as well, effectively I'm using lumens to make a roughly accurate PAR watts target.

I would target between 5500lm/sqft and 7500lm/sqft. Or something like that in PAR watts.

I only use lumens because PAR watts are not always listed if the product isn't made specifically for growing. Lumens are listed on every light type.

Wrong again as usual nomo,you don't have a single CXA3070 grow under your belt but act like your a expert on them. I've gotten 1.2 to 1.4 gpw on 3 straight grows with 3070's at a little under 35 watts sq/ft. Check with other high bin 3070 users,over 35 watts sq/ft will have diminishing returns.

My watts per sq/ft # includes drivers,cooler fans and fan PS.

captainmorgan said:

Wrong again as usual nomo,you don't have a single CXA3070 grow under your belt but act like your a expert on them. I've gotten 1.2 to 1.4 gpw on 3 straight grows with 3070's at a little under 35 watts sq/ft. Check with other high bin 3070 users,over 35 watts sq/ft will have diminishing returns.

My watts per sq/ft # includes drivers,cooler fans and fan PS.

Click to expand...

Diminishing returns = more grams but less grams per watt, correct?

If we imagine a 1sqft grow area with 35w of CXA3070 vs a 1sqft grow area with 50w of CXA3070, what one will produce more grams? I expect you will agree the 50w one will produce more grams.

If so then that is exactly what I said and you need to read again.

Sounds to me like you actually agree with me, but just don't like me, lol.

You won't pull me into another argument with you nomo. You've proven over and over again that no matter what facts are given to you by more knowledgeable and experienced members here,you think your never wrong. I'll just be hanging around to call you out on your bad advise and info.

captainmorgan said:

You won't pull me into another argument with you nomo. You've proven over and over again that no matter what facts are given to you by more knowledgeable and experienced members here,you think your never wrong. I'll just be hanging around to call you out on your bad advise and info.

Click to expand...

Lol, sounds to me like you just figured out you read it wrong and are on the wrong side.

Actually time has proven I admit when I'm wrong.

Can you please point out where I was wrong? Like I said I think you read it wrong. I will be here to do the same for when others post false info.

Do you have a target you would aim for that applies across light types? You can't compare them without using an output measure like PAR watts or lumens. 30w per sqft of CXA3070 will put out far less par watts and far less lumens than a 600w HPS over a 4x4 (16sqft, 37.5w/sqft) area. You can't reasonably expect it to compete in total grams of output. To maximize the output of a given space you need ideal light levels, this will result in less grams per watt, but more total grams.

You do realize the most grams per watt is not what most people are targeting right? You need to understand that most people work in limited space and want the most grams they can get out of it or the best weed they can get, not the most grams per watt.

dark76 said:

Is there a collection of formulae I should be using when selecting the COBs, Drivers, etc? I seem to recall seeing one before, but I may be mistaken.

Click to expand...

The best starting point would be to determine what your current setup is putting out in par watts/sqft or lumens/sqft and make sure your new system at least matches it or you will likely be disappointed.

For ideal lighting: Find a source you trust that recommends an ideal lighting level in par watts or lumens. Preferably this would not be a person with an avatar, instead find a professional or edu source of info you trust to determine your target par/lumen levels.

Sizing of lights should be based on the output of the lights (par/lumen), not the input/consumed power(watts.)

Do not use lumens when sizing, space.

*twiddles thumbs*
*waits for bullshit to start again*