Lighting What should be on a grow light review?

[Wsg]

Well stated! In a perfect world a led with 200w draw should replace a 1000w bulb. Why you ask......if led is created to be 5x more efficient the true measurement is 1/5 of the hydro consumption. With cob we can see the difference by eye, we don't need meters to tell us it's brighter. The true question is just how much efficiency savings

Led rated at 300w by many manufactures draws 135 seems standard across the board so we are saving about 1/2.

Seen some good grows under a 300w panel 1 plant
Typically 250w is what I would use on a plant.

 

[Rev. Green Genes]

Well stated! In a perfect world a led with 200w draw should replace a 1000w bulb. Why you ask......if led is created to be 5x more efficient the true measurement is 1/5 of the hydro consumption. With cob we can see the difference by eye, we don't need meters to tell us it's brighter. The true question is just how much efficiency savings

Led rated at 300w by many manufactures draws 135 seems standard across the board so we are saving about 1/2.

Seen some good grows under a 300w panel 1 plant
Typically 250w is what I would use on a plant.

That is true, I use a 200 watt draw blurple for one plant, but in my grow style it is not enough. It's not a matter of watts, or brightness that limits me though. It's coverage. My grow style makes bigger plants, it take more lights to cover them at 8-15 inches from plants. I run the lights to the ceiling almost every single grow.

 

[SPZ]

@SPZ your two posts above are BAD-ASS!!! much REP deserved, my share given! Your spreadsheet shows that we SHOULD be able to review and document the critical parameters that affect lighting performance. I imagine you have invested weeks of effort into that, good job!

Thanks for the kind words! The sheet did take some time to compile, I've been researching a bit every day for a couple weeks and adding to it. There are still some really great companies that I want to add, looking at Platinum LED today. I also want to add a cell in the sheet where I can add the price I pay per kilowatt hour so I can figure out the total cost of ownership over a period of time.

Still, I believe many lighting vendors are recommending that comparisons be based upon ppfd. I totally understand your decision on ppf – not faulting it whatsoever. But shouldn’t our objective be to define the best industry standard measures, how they are taken and how to present the results?

This is the case and I believe that it is for the most part because PPFD can be measured with a handheld device that costs a few hundred bucks, whereas PPF requires lab testing (unless you own an integrating sphere which obviously not the case for small shops). Most vendors do not publish the PPF. ChilLED is the only vendor that I've found that publishes actual lab reports of their units AND their competitors!

The only thing about PPFD is that the measurement depends on the testing equipment used and the testing environment and it is hard to trust all the vendors out there. I am considering adding a column to the sheet for the center PPFD measurement at 18", which seems to be available for most high-end lights. Of course, just putting a lens on your light will boost this metric which is partly why I don't trust it!

OH... BTW, I took a deeper look at your PPF ranges. If I eliminate the two low 1.89's and one high 2.92, I end up with a range of 2.0 to 2.45 PPF's per watt, at a mean average of 2.27. So even if I picked the absolute worst (and still only real) measure possible in watts-at-wall, it still looks like the deviation is not so severe as to invalidate my study. I'm filing that away for future reference.

That was my takeaway as well, but keep in mind that this spreadsheet only compares quality vendors that are using top shelf components and driving them effeciently. Many of the cheaper LED vendors overdrive their components. This gives them high watts and a low price, which the marketing team likes, but they sacrifice efficiency so you really pay the price in the long run with high electric bills and reduced yield. If you look at some of the cheap Chinese vendors (not naming any names here) they are sometimes getting about 1.5 PPF per watt or worse, so you'd frankly be better off with HID's.

 

[The Green Sunshine Co.]

All very true points. PPF does matter, however spectrum and overall PPFD over the area matters a lot too. Any light hitting a grow tent wall loses a significant amount of light, so while a fixture could be 3.5 PPF (woah) if it pointed it mostly at the sides, then, your plants in the middle are going to be a little sad.... this is why lenses and fixture design matters and also the PPFD. It also matters the meter that took the PPFD readings, and also the grow tent environment.

I would encourage you to look up the migro channel: he is one of the most dedicated light testers I know

Note that the QB board is rated very high (2.1-2.3 umol, I cant remember) but since so much light goes "horizontally" to the sides of the grow tent, when measured at the surface of the grow tent, it is less than 1.9 umol because the light is so scattered and hits the grow tent.

Additionally, when growing indoors, we are leaving out colors from the sun, and the proportion/ratio of colors significantly changes how plants grow. Plant's don't just indiscriminately soak up photons -- each color changes taste, potency, size, shape, ability to penetrate canopy, contribution to photosynthesis, contribution to other biological processes in the plant. So while efficiency is great and all, it also matters how your plants are growing under the light. Want fast growth? slow growth? high THC? High Yield? There's a spectrum for that and there isn't a perfect one.

And at the end of the day whatever gets us into the garden growing and the lights that encourage us to do that and zip open that tent ... we all win!

 

[SPZ]

All very true points. PPF does matter, however spectrum and overall PPFD over the area matters a lot too. Any light hitting a grow tent wall loses a significant amount of light, so while a fixture could be 3.5 PPF (woah) if it pointed it mostly at the sides, then, your plants in the middle are going to be a little sad.... this is why lenses and fixture design matters and also the PPFD. It also matters the meter that took the PPFD readings, and also the grow tent environment.

I would encourage you to look up the migro channel: he is one of the most dedicated light testers I know

Note that the QB board is rated very high (2.1-2.3 umol, I cant remember) but since so much light goes "horizontally" to the sides of the grow tent, when measured at the surface of the grow tent, it is less than 1.9 umol because the light is so scattered and hits the grow tent.

Additionally, when growing indoors, we are leaving out colors from the sun, and the proportion/ratio of colors significantly changes how plants grow. Plant's don't just indiscriminately soak up photons -- each color changes taste, potency, size, shape, ability to penetrate canopy, contribution to photosynthesis, contribution to other biological processes in the plant. So while efficiency is great and all, it also matters how your plants are growing under the light. Want fast growth? slow growth? high THC? High Yield? There's a spectrum for that and there isn't a perfect one.

And at the end of the day whatever gets us into the garden growing and the lights that encourage us to do that and zip open that tent ... we all win!

Good points, couldn't agree more. One of my main takeaways from my research so far is that any quality light from reputable vendor (present company included) is probably going to perform great for growing cannabis and which one you choose depends on your individual needs! By way of the car analogy, I can say that my wife and I both drive vehicles which have roughly the same fuel economy and horsepower, but hers is a sports car and mine is a pickup truck, couldn't be further apart as far as functionality. We would not drive my truck on vacation, nor hers to the lumber yard.

But when we drive to work--the majority of the miles we travel--we both use the same amount of gas to go the same distance, and that is a number I want to know (even if it sucks for both our cars lol). Grow lights are machines that turn electricity into photosynthetically available radiation, and I think it is fair to ask how efficiently any particular light does that basic job. I'm not saying that PPFD and spectrum don't matter, they are just harder to compare apples to apples, and as you said, there is no "best" solution as it depends on your situation. In the case of the QB boards, if you just put some flimsy little reflectors on them you get the 15% loss back:



On the one hand this proves your point about how much reflectors and lenses really do matter, but it also shows how changing one variable in the field completely changes the PPFD readings! Don't worry, I know I'm beating a dead horse, the majority of vendors aren't going to start publishing PPF numbers any time soon and it is not that important in the scheme of the universe after all.



I've lost a few hours watching the Migro youtubes over the past few weeks! I hope to put the Migro units on my spread sheet as well, they look like really solid lights and the design spreads out the light and lets you angle each cob individually almost as good as the autocobs with some added benefits as well.

Those electric sky units y'all have don't look too shabby either All the 420 sales start tomorrow and you're not making this decision any easier!

 

[The Green Sunshine Co.]

Oh yeah, definitely put those reflectors up.

Just because I like expanding and widening the rabbit hole, here's some more food for thought:

A 6500K LED will beat out a 3000K LED any day of the week in terms of PPFD / PPF readings. But... which one is gonna grow better? the 3000K with more yellow/orange/red/IR. So PPF/PD is just small foothold on reality

 

[SPZ]

Oh yeah, definitely put those reflectors up.

Just because I like expanding and widening the rabbit hole, here's some more food for thought:

A 6500K LED will beat out a 3000K LED any day of the week in terms of PPFD / PPF readings. But... which one is gonna grow better? the 3000K with more yellow/orange/red/IR. So PPF/PD is just small foothold on reality

Of course every strain would have its optimal spectrum, and that optimal spectrum would ideally change throughout the grow.... yeah it is a rabbit hole all right!

 

[The Iconoclast]

What information do you think grow light makers should include on their product descriptions for grow lights?

What is useful? What charts are useful to accompany the information?

Devil's advocate, what information can be skewed? What can be manipulated? How can that be verified?

PPF?
PPFD?
PAR?
WATTS?
Efficiency/Efficacy?
Spectrum?

I'm working on building out a new review template for grow lights on here and I'd like to know what people would like to see as a standard template.

Likewise, I simply would like to know what the community thinks about a standard for lighting companies to give us specs on.

What makes you NOT want to buy a grow light? What makes you go "ohh, more of THIS crap, no thanks?"

I really think we can start setting some standards as growers and demand that manufacturers start complying with the information.

What do you guys think? What should be on the list? What should be on the review?

For my money, I'm only interested in spectrum and par distribution over the area primarily. Spectrum including control over the spectrum is the most important for me and PAR only has any meaning if I know the spectrum. Then given that, I will look at secondary concerns (for me) like efficiently and especially cooling.

I'm only growing small so considerations like par spread may not be relevant if I was growing with more lights, and individual spectrum control ditto if I had more lights.