LED vs. HID Double Ended Bulb

Honestly, a lot of the claims in favor of LEDs have little grounds in the laws of thermodynamics. I'll give you that! I've been watching these LED threads since the red traffic light grows, and only now decided it's worth investing my own personal resources!

Assuming 35% efficient LED and 35% efficient HPS, they will generate the same amount of heat and the same amount of photons per watt of electricity. Those heatsinks aren't for show.

One thing that can't be ignored is that COB growers are using 30W/sqft and getting great results. Any more and you start getting light bleaching.

Sativied said:

That theory about light turning into heat in any case apparently isn't solving that issue in practice (and that's not just winter, it's more like not-summer). Heating with natural gas (that's how we heat greenhouses as well as our homes) is a lot more expensive. That silly issue is recognized by for example philips as well (posted link or flyer in a previous discussion).

HPS in combination with a balanced intake-exhaust setup allows for plug and play while with LED it requires additional efforts. I should be able to overcome it one way or the other because I only have a 4x4 closet opposed to an entire room, but I can't simply dismiss the issue as if it doesn't exist.

As with other negative aspects of LED, LED fans tend to turn those negatives into positives. While I applaud such an approach, let's keep it realistic... Although I admit I got the info from LED growers, the claim that LED results in a cooler environment and for example not having to use a cool tube (which I've never even seen in real life... blocks too much heath...) seems to be quite a persistent argument, and that instead of at the canopy, the heat is emitted from the top. Thought that was a typical LED thing. The fact is that's not always desirable.

It's not like people here don't try out LED, growers, as well as grow shops looking forward to cash in on a LED trend, as well as the greenhouses with tens of thousands 1k Gavitas... (I do see a trend in LED as supplemental light).

Yes, startup cost is still a big argument, in fact, if LED were truly that much better, the prices of professional complete setups would be much lower already. We'd be all over it... I get that it's fun to hobby with COBs and some get fine results but frankly I can't take those threads serious when it comes to HPS vs LED.

Yes, "LED is the future".

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You mention a balance intake system for hps...why would you use something balanced for hps on an led...?
Balance the intake for the led...it's that simple. I don't understand how that doesn't make sense to you.
If you are trying to replace a 1K with <500w...there might be a lack of heat issue...but if you are using the correct amount of wattage to match the photon output of the hps...then the direct heat should be sufficient. As for needing the carbon filter to dehumidify...real grow setups are meant to keep the environment perfect, or deal with it. You might as well just get out of here and never worry about led's...if this is your problem(that plenty of people don't have)...it will never get better. LED are only getting more efficient...and thus less direct heat per watt. Your shit out of luck. Keep growing with hps.

Attitudes...it's because led users(specifically the RIU crew) are pretty educated about light and plants response to it. As where hps just regurgitate what they hear and/or what they have been doing...but not why it works, and usually are off base when they try to expialn it...doesn't mean it isn't working, just that they don't understand it. In the end LIGHT IS LIGHT. There is no difference in a 600nm photon from a hps or led...it's just a 600nm photon. Just as there is no difference in heat from an led to hps(assuming equal efficiency) watt for watt. But even the best led's driven to max efficiency are only 3-5% more efficient than hps(new)....so 3-5% less direct heat lost in conversion. And most are equal or less so they are actually producing more heat per watts than good hps in many cases...problem is when people use 50% less wattage... they aren't seeing how much it produces watt for watt with what they are used to.

As for you take on the at600...guarantee your thoughts/feeling have noting to do with the light...just the cost...it is probably the light that you would use if you could have one...just saying.

And the margins on an actually top performing LED is shit and hydro stores want nothing to do with that...ya it's 2400$ to the customer but then shop is only making about $500...not worth their time or space...and even if drop shipped the margins just aren't there.

As for big ops and prices...buy 50-100...or even 500+...economies of scale my friend.

Greengenes707 said:

your thoughts/feeling

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barking up the wrong tree... Just because LED growers are so enthusiastic about LED doesn't mean HPS growers have the same level of emotions towards the matter. Hence the "fanboy" reference. HPS growers don't have something against LED like LED growers have against HPS. Like ex-tobacco smokers talk about smokers... it's just rude.

Greengenes707 said:

it is probably the light that you would use if you could have one...just saying.

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Could? and you're entirely missing the point of me bringing up the AT600.

Greengenes707 said:

I don't understand how that doesn't make sense to you.

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Then you probably won't understand how that sentence alone just doesn't even compute for me and I won't bother explaining what you don't understand. Really, if I wanted to have a discussion on that level I'd be joining one of the defoliation threads...

churchhaze said:

Those heatsinks aren't for show.

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No they're not for show indeed, but they are pointing in the wrong direction. While those claims about temps may not be accurate it's still an often perceived benefit that LED is cooler on the crop. That simply isn't always desirable. Maybe for those how use a cooltube, but again, I never even seen one of those (stepped into a grow shop the first time over 20 years ago, use to go there for coffee in the morning).

Anyway, seems pointless to discuss with those who simply don't recognize the issue. Unfortunately that isn't the reality for everyone (read: hundreds of thousands of growers). I'll find a solution when the time comes. Which may be sooner than I expected.

churchhaze said:

I've been watching these LED threads since the red traffic light grows, and only now decided it's worth investing my own personal resources!

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I noticed you became more active in LED threads, figured you were bored and trolling led growers... Seriously, I take a peak at your posts now and then, knowing how you approach nutrients. Seems like a fun hobby, but be careful, don't gaze at those pretty lights too long. It seems long term exposure affects more than just vision.

Sativied said:

How is that even an argument... during lights off there's no photosynthesis, the main reason to keep the temp at an optimal range. Comparing types of light... but then you turn HPS off. And of course I insulate my closet, that neither is somehow an argument.

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Of course there is no photosynthesis during lights out, but that does not mean the lights out temp does not matter. It is especially important for organic soil growers. What I am saying is that if your grow environment is that cold, HPS is not going to solve your problem alone so the "cold environment" theory is not an argument against LED. LED can be used just fine in cold environments by recycling air/flip flop, insulating and slowing down your ventilation. There is no reason to use a heater. I am speaking from experience it has been done.

Sativied said:

Slowing the ventilation down during the colder period would be similar to throwing a bucket of water over my plants... a bad idea. It also assumes overcapacity or implies a huge undervaluation of proper ventilation. It's not that different from suggesting to turn the light down as a solution. Same goes for heating one room with the other, good recipe for bud rot and pm. I need the exhaust to extract the humidity, not attract it from another closet.

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Slowing down your ventilation will not starve your plants for CO2 and it will not decrease yield. If anything I have too much CO2 more often than not. The only problem with slowing down your ventilation is choking on the heat from HPS bulbs.

Whether you are using HPS or LED, humidity is a problem for large grows. I have been recycling the indoor air for years during the hot/humidseasons. I control the humidity with dehumidifier during that time. I have never had PM and as long as I keep 60-65% RH I never have to worry about bud rot. I used to push my luck by running above 65% RH and there was occasional very slight bud rot (unacceptable).

If you are interested in actual numbers, I use a pair of 6" Max Fan mixed vent fans set on low (120W total) that run 24/7/365 and ventilate all 4 grow tents, always pulling the heat from the flower rooms into the veg room. That is about 400CFM but they are pulling through a layer of carbon so it is moving less air. It is very quiet which I appreciate. That is enough to ventilate the grow most times of year but in the summer I kick them up to medium (140W/500CFM). That keeps canopy temps under 80F.

churchhaze said:

Honestly, a lot of the claims in favor of LEDs have little grounds in the laws of thermodynamics. I'll give you that! I've been watching these LED threads since the red traffic light grows, and only now decided it's worth investing my own personal resources!

Assuming 35% efficient LED and 35% efficient HPS, they will generate the same amount of heat and the same amount of photons per watt of electricity. Those heatsinks aren't for show.

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Very important point to keep in mind. The cheap commercial LEDs may be as low as 20% efficient and the good ones may be around 30%. With DIY is is within reason to go as high as 49%. The primary heat advantage of a good commercial LED comes from needing less watts to do the same job, due to the cone shaped directional output. I know you know this CH, just reiterating it for those who may not.

Sativied said:

No they're not for show indeed, but they are pointing in the wrong direction. While those claims about temps may not be accurate it's still an often perceived benefit that LED is cooler on the crop. That simply isn't always desirable. Maybe for those how use a cooltube, but again, I never even seen one of those (stepped into a grow shop the first time over 20 years ago, use to go there for coffee in the morning).

Anyway, seems pointless to discuss with those who simply don't recognize the issue. Unfortunately that isn't the reality for everyone (read: hundreds of thousands of growers). I'll find a solution when the time comes. Which may be sooner than I expected.

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My biggest problem right now trying out cobs (vero 29) is burned leaves. It's like a portal to hell about the size of a quarter, and I've got 6 portals to hell. If you hold your hand 3 inches under one of them, even at a low current, the light will burn your hand with no lenses or reflectors. It's like burning ants under a magnifying glass.

I designed panels for another cabinet with smaller cobs just because the vero 29 were too intense. Burned in the middle, nice flowers on the outside! It's actually too powerful!

Sativied said:

I noticed you became more active in LED threads, figured you were bored and trolling led growers... Seriously, I take a peak at your posts now and then, knowing how you approach nutrients. Seems like a fun hobby, but be careful, don't gaze at those pretty lights too long. It seems long term exposure affects more than just vision.

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Yes, I'm guilty.. I've always been interested in LEDs, but have recommended HPS until recently. Now I honestly don't know what to recommend. I feel old now. I'm sure it will all become more clear in a few more years, and everyone will act like it was obvious all along what the future would look like.

I think the average LED grower is a lot smarter than back in the day, and RIU currently has some pretty good engineer-minded people in the LED section. I'm actually impressed, as I generally have a lack of faith in people! Things are a lot different than they were back when everyone quoted the chlorophyll absorbance charts as the only factor in determining how good a light is. Now, almost everyone is focused on results rather than theory alone! People constantly come in to teach us how all you need is red and blue, and they are quickly ridiculed!

What ultimately convinced me to try leds was people consistently reporting above 1g/W. I know that's not the best measurement of successful, but in general, I thought it was time to give it a try if I could get over 1g/W! I keep seeing yields of 1.3g/W and being blown away... jealousy quickly sets in at that point!

Also, shameless plug for my 80W UFO killers! (meant for cabinets)

The 3 panels are meant to cover a 2'x3' cabinet. I have another cabinet that uses (6) vero 29, and wanted them more spread out, so 12 of the smaller ones instead! The vero 29 was too intense in the middle.

http://rollitup.org/t/diy-80w-vero-18-ufo-killer.846752/

I do admit, sometimes I wonder if this is all a good idea! It's obviously way more expensive per watt to setup than HPS, even being a DIY setup.

Sativied said:

I noticed you became more active in LED threads, figured you were bored and trolling led growers... Seriously, I take a peak at your posts now and then, knowing how you approach nutrients. Seems like a fun hobby, but be careful, don't gaze at those pretty lights too long. It seems long term exposure affects more than just vision.

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Sativied said:

And again the typical disappointing LED grower response showing you just want to be a LED fanboy rather than have an actual discussion about it.

The rooms that do use heating, which unlike you assume is not by default the case at all (switch day and night... room temp during the dark day, optimal photosynth temp during light night...), would have to combat that regardless of type of lighting obviously, making your point anything but valid. How many of those pro grow rooms do you think grow with LED... Google 'hennepkwekerij' and see images results for hundreds of (raided) examples.

Do you LED folks think before you write or just post random thoughts?

HPS grower: I need the heat from the HPS
LED grower: then how do you handle that when the light is off...
HPS grower: what a silly argument
LED grower: yes but temp fluctuations

Downright childish and frankly not even worth dignifying with a reply................................... (just want to show my dots are longer too)......................

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^^Sure, I'm the only one acting childish ...................................................................<<actually my terminal punctuations are longer than yours..........................................................................lol

Here you go with your assumptions again! I'm rather new to led growing(4 yrs), outdoors & hid most of my life. Tried most of the indoor lighting tech now except for mh/sulfur plasma & DE hps.

What do you think is the most important thing to a commercial cash cropper ?====== hint, CROPS. Personally know for a fact that HID gives the biggest temp fluctuations @ the canopy . v Cold ^ HOT v Cold /etc. causes CONDENSATION , which last time I checked isn't the greatest thing for dense flowering annuals. Maybe it's just my random thoughts though.....OR a major concern of the pro growers I've visited in holland years ago.

btw this is what they use ( I asked because their fucking awesome) and it's widely accepted as the go-to EFFICIENT solution in modern commercial dutch grow rooms


http://opticlimate.nl/

Gavita/Philips for lighting, H&G/Aptus line for ferts exclusively; see a trend??? The dutch TRUST/LOVE their own products, their is NO led panel being made there for primary lighting by the top names. Don't see them switching to it anytime soon regardless as I stated earlier in this thread .

You've gotten some good advice in here, yet you toss it aside and belittle all the posters...........I think some cannabis is just what the doctor ordered

churchhaze said:

What ultimately convinced me to try leds was people consistently reporting above 1g/W. I know that's not the best measurement of successful, but in general, I thought it was time to give it a try if I could get over 1g/W! I keep seeing yields of 1.3g/W and being blown away... jealousy quickly sets in at that point!

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It works pretty well 'if' you take into account an matching sized surface, a not unimportant given. I.e. LED growers often fail to mention that that increased gpw involves more space than the same wattage in HPS, or it's purely relatively, as in they don't got more yield, they use less watt to get the same. Pretty sure Groerr got more than that too with the elite agro bulb.

I remember being surprised when I noticed at rollitup people are called liars when they get 1gpw+ - older topic in hydro forum I think - as if that's so special. After 30 years of indoor growing in tight spaces that just isn't so special around here. It's like with defoliators claiming "it works", always ask for gpw before you enter in a discussion.

churchhaze said:

My biggest problem right now trying out cobs (vero 29) is burned leaves. It's like a portal to hell about the size of a quarter, and I've got 6 portals to hell. If you hold your hand 3 inches under one of them, even at a low current, the light will burn your hand with no lenses or reflectors. It's like burning ants under a magnifying glass.

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Yeah good analogy. The spread of an HPS isn't that big of a negative as LED promoters usually claim, just like the directional light not being that big of a positive either.

churchhaze said:

I think the average LED grower is a lot smarter than back in the day, and RIU current has some pretty good engineer-minded people in the LED section. I'm actually impressed, as I generally have a lack of faith in people!

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More informed perhaps, not sure about the smarter part but it's irrelevant to me as I don't ambition a hobby to create LEDs and when it's (really) time I will buy a professional LED setup designed, created, and tested by professionals that are also able to interpret results. Engineer-minded people, LED, "and" RIU just seems like an extremely unlikely combination. Much is just the same old poor discussions and LED evangelism I've been hearing for so long And they do get bitchy...

PSUAGRO. said:

Gavita/Philips for lighting, H&G/Aptus line for ferts exclusively; see a trend??? The dutch TRUST/LOVE their own products, their is NO led panel being made there for primary lighting by the top names. Don't see them switching to it anytime soon regardless as I stated earlier in this thread .

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Another childish invalid argument. H&G and Gavita both produce quality products that are used by professionals. It's the results of actual research by actual professional with educations, labs, universities, and many greenhouses working together that we're the 2nd largest exporter after the US, but using very little space. It's a science here, not a belief, not some thing to think is cool because you made it yourself... Why import something if you can get high quality professional horticulture gear locally... H&G for example is not expensive for me. I use less than $20 per run. I also used GHE, Canna, Plagron, several organic products though. It's ridiculous to think there's some sort of nationalistic reasoning... absurd... It's all about the money, if chinese imported crap would suit better it would be the most popular.

PSUAGRO. said:

You've gotten some good advice in here, yet you toss it aside and belittle all the posters...........I think some cannabis is just what the doctor ordered

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I think you need to buy a mirror or turn on your webcam... hypocrite. As usual you resort to ad hominem because you take any critic on your LED religion personally. What else is new...

It must make companies mad when someone can put together a grow light in a few hours and have it work as good or better than anything commercially made.

Guess what regular joes think about professionals and universities putting themselves on a pedestal..

Unfortunately for them it's not rocket science. My money stays in my pocket. No need for a new bulb every other run. My money goes straight to the producer of the technology not a middleman "professional"

Let me rub my crystal ball.....

The future is cobs running the length and width of a warehouse. If the pros are smart enough.

The directional light advantage is that it doesn't shoot up. All cobs have a relatively wide angle of 60 degrees from the center, where intensity is 50% of the center of the beam. After 60 degrees, it tapers off.

(you combine the 60 degree right triangles of the cone to get a 120 degree isosceles triangle, and you've got a pretty good beam pattern.

You'll get a lot of different opinions on whether reflectors and lenses are good or bad, but these cobs at the base come with no optics attached. I think no optics is the most practical route.

I personally do not like lenses, as they attenuate light, but if money was no object, I would use 60 degree reflectors to reflect all intensity lower than 50%.

A 40% efficient COB setup already factors in the losses from a reflector, while half the lumen output of the HPS still has to be reflected, which isn't 100% efficient in itself. This is why a lot of HPS growers do vertical grows to avoid the losses from reflector.

Sativied said:

Yeah good analogy. The spread of an HPS isn't that big of a negative as LED promoters usually claim, just like the directional light not being that big of a positive either.

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churchhaze said:

The directional light advantage is that it doesn't shoot up.
[...]
This is why a lot of HPS growers do vertical grows to avoid the losses from reflector.

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Yes, but it's at the same time being directional is a disadvantage, hence the lenses which were developed as a sort of patch rather than a solution.

A reflector isn't that big of a downside, especially a proper one (i.e., I almost not dare say it out loud, a Gavita or other quality hood). It allows the grower to direct most light (and there's the heat thing again) to the the surface uniformly given the omnidirectional light source. Kind of a moot point imo especially once more than one or a couple of bulbs are involved. Overlapping multiple HPS bulbs with quality reflectors is what pros do to create and optimal even spread.

My point though was that the lack of spread of LED (both an advantage and disadvantage) is somehow turned into a disadvantage of HPS (which is then typically followed by the reflector argument). HPS + hood = flexibility. If the goal is to save on electricity at all cost, then sure, I'd be worried about the loss from reflection.

The benefit from a vertical grow is primarily using the space more optimally. If you'd roll out the canopy to a regular horizontal and use 2x300 instead of one 600 you get the same results, possibly even better. Loss from reflection is hardly a factor especially since in vertical grow they still light the ceiling and the floor, which typically unlike the walls in a proper horizontal hps setup do not reflect. I've actually drawn it out for a vertical grow here in the hydro forums a while ago, they could benefit from (cone-shape) reflector at the top.

So, which one is next. Better taste under LED, test results that show certain terpenes only appeared under LED, efficiency decrease of hps bulbs over time, better spectrum?

Positivity said:

Unfortunately for them it's not rocket science. My money stays in my pocket. No need for a new bulb every other run. My money goes straight to the producer of the technology not a middleman "professional"

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Well perhaps I'm wrong to expect millions of dollars of research for a billion dollar industry to lead to a far superior grow led than both HPS and the DIY toys in mj forums. I've seen crazier things happen. For example, and this may come as a shock, but those pros and people working at universities... they are also just regular joes too, but since they're pros, they take they "work" a little more seriously.

Sativied said:

Well perhaps I'm wrong to expect millions of dollars of research for a billion dollar industry to lead to a far superior grow led than both HPS and the DIY toys in mj forums. I've seen crazier things happen. For example, and this may come as a shock, but those pros and people working at universities... they are also just regular joes too, but since they're pros, they take they "work" a little more seriously.

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Yeah...you'd think they'd have a far superior grow led.

But right now a arctic CPU cooler and a good cob beats them all.

Good luck improving on it. I'll buy it for a fair markup.

One thing is for sure, the popular cxa 3000k warm white 80cri spectrum does have a lot of resemblance to HPS's spectrum, only with more blue, and a steeper R:FR gradient. HPS has more far-red (730nm), which means more stretch.

I think many here would agree that it's the ambers, yellows and oranges from HPS that make it such a great light, and realize R+B lamps alone just don't do a good job flowering.

Let's put it this way... 10 years ago, LED growers had to come up with excuses for their terrible results. "but red and blue are more efficient!...." yeah... it didn't work... Now, with warm white cobs, the results are amazing, and everyone is struggling to find out why red+blue was such a failure, but warm white cobs are kicking so much ass in practice.

Positivity said:

Yeah...you'd think they'd have a far superior grow led.

But right now an arctic CPU cooler and a good cob beats them all.

Good luck improving on it. I'll buy it for a fair markup.

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Yep, all those engineers and geniuses have been unable to bring anything to market higher than 80lm/W and they run so hot you can't touch them. I saw some dime-sized COBs in Home Depot a few months ago, 70 lm/W. Granted they were not engineered with growing in mind but because of their overhead that is the best they can do. I use homemade LEDS all around the house that are 170-180lm/W and some vegging lights that are 200lm/W. This is one of those cases where you can't beat DIY.

It was not built for looks, but turns out 200lm/W at running temp (60% efficient) and built to last a lifetime.

@ Sativied :
Look brother ...I'll tell you what's next .....
Myself & my personal needs ,is next ...

I'd been growing with HPS ( 400W Phillips GreenPower ) for long enough time (>5 years) ,
always seeking to cover my personal needs of herb . All this time It never went over 280-330 gr...
Per grow cycle ..( Average duration : 4 x7 x18 hours veg & 10x7x12 flowering ) .
I do not give a $hit about greenhouses or crop /cash growers ...I do not care about their problems or
needs or whatever ...

What I do care of though ,is that now ,from same space/room ,same nutes ,same grow cycle duration ,
same old " LAI" grow method ( Leave As Is ) ,I do get 480-530 gr of herb .Almost double than it used to be ...

And guess what ...I use same power as before ...
Around 400 Watts ..( A bit less than before ,actually...)

Only this time ,HPS is long ago ditched ...
Now ,if you want ,you can go on saying whatever you like ....
Personally I do not mind or care really ....
I do not have to prove anything to anyone ...
One happy grower ,that I am !
And no it did not cost me a fortune ....
In fact ,it is a quite cheap 'hobby' ,making lights that they will last 10 to 15 years ....
But ,nevertheless ,it all comes down to this:
All I know-poor but happy me - is that I've almost doubled my yields and yes ....
Led herb is superior to HPS herb ..
Whether you like it or not.
Believe it or not .
(FGS ! Just try it once ,bro ! )

As MH herb is superior to HPS herb ....
HQI herb is even far superior than HPS herb ...

( You see ,here in this part of the world,
we're still about 100 years left behind than the rest of the world ,
in almost every aspect of everyday life ...
There're still people growing with "bare" HQI (unshielded mercury vapour ) bulbs ...
Yields are for laughs,but quality is unearthy ...
Please do take my word on that one ! )

So ....
From me you can have a nice day ,and by all means do whatever you like .
Just try -if you wish to do so-, not to neglect this :
Some things you just can not change ...
Or stop ...Inhibit ...
Say for example ,you can not stop ,'things' evolving ...
...
Unless again,you trust that some things will & shall never change ..
Like technology,for one thing ..
Or the fact that the Earth is flat ,dead-still and is the center of the whole universe ..

Bitchy ,but honest to the bone ...

---------------------------------------------------------------------------------------------------------------------
@ churchhaze :

Blue and red leds do work ....
They 're a perfect match ,supplementing sunlight or HID lights ..
But that goes only for greenhouses ...

For more 'domesticated' applications no ,they won't 'fit'-work just by themselves that's been proven alright ,but remains also the fact ,that designing a fixture ,which implements monochrome leds ,is way' tricky ' in so many aspects and not so simple as many like to think it is.

Still ,I'm not personally quite sure that is the high radiometric efficiency of most COBS vs
HID lights ( HPS ,mainly ) that is accounting for that + 25% ~ 50% in yields .

( CXA3070 top bin cobs yield,at average ,
35%-50% more than HPS of same wattage ) .
Little story that repeats itself ,per approx 6 months,in a world-wide scale :
From .5 -.6 gpw for a 'newbie ' to growing with HPS ,
straight to 1.2 -1.3 gpw onto the next grow with CXAs .
Newbie remained newbie ..
Space was the same ...
Nutes the same ...
So it must be the lights ,that made that whoppin' difference ....

Anyway,plants do seem to be really affected by light quality only in low-light conditions and
during the very first stages (but crucial enough ) of vegetative growth .
Blasting a young /small plant with monochrome leds ,
might be 'preparing' / 'shaping' the plant in wrong ways .
Later ,under the same illumination ,the same plant seems to be far from it's ideal genetic potentional vs energy supplied .The plant is 'under-performing' .

While ,at high irradiances of white light,only then it seems that mj really 'performs' outstandingly !
But yet ,if different CCTs of white are being used ,then the same genome ,
will be expressed by distinctive different -in plenty of aspects -phenos/phenotypic groups...
As it always have been so ,with different types of HID / fluo ,
but of same more or less , total irradiance ...
Thus ,I think that the light quality coming out from those 3000 K led arrays ,
makes a difference ,too ...
Not probably ,so much from a direct photosynthetic enhancing /synergistic effect of some sort ,but rather from indirect photomorphogenic metabolic pathways.
Photomorphogenesis is the crucial 'parameter' here ...
Originating from hellenic :
Φως {Phos} =light + Μορφή {Morphee} = shape/outlook + Γέννεση { Yhenesee } =birth
Birth of an outlook ,'cause of light ...
That 's is the meaning of it ...

The macroscopic expression of the 'interaction' between DNA (genotype) with light ,( with the latter being the #1 environmental life-sustaining variable for species involved ,as it is the prime energy source at the same time ) ,in the form of a certain plant physiology (phenotype)..

Back to ....3000K SSL 80 CRI ...
...More blue & red wls than of HPS ,less FR ,less Green ,about same amber/yellow wls ....
That probably affects the light quanta total capture mechanisms and physiology,the photo-systems' I & II photosynthetic "load" level & interaction between ,the accessory pigments & light capturing protein complexes' concentration & biosynthesis ,the photosynthetic capacity /recovery mechanisms and many more plant bio-tech stuff going on inside the cells of our precious herb ,as we speak ...
Still,they might be some things 'outta there' ,that we're still unaware of ...
Regarding the interaction between light and living plants .
Specially,regarding light & our beloved herb ...

What we 've been seeing / witnessing so far ,is an emerging 'trend',
a clear & strong indication ,-that eventually will prove to be a solid state -and absolute -fact :
" Nothing beats the quality & quantity of herb ,white COB leds yield ."

Comin' real soon ...



( Until further notice,at least ...
Can't be 100% sure ,with all those led manufacturers ..
Their sleeves seem to be packed ,full of hidden Aces ..)

Cheers.

This is what I've been using as a light source ,some years ago ...
420 actual Watts ( not 400 Watt as claimed ) and 725 umol/sec( range 300-800 nm => estim. for 500 nm range )* .
That makes a ' score ' of 1,726 umo/ J .
For 12 hour DLI it translates to 31.32 mol .

Now ....
6x CXA3070 Z4 operated at High Efficiency mode (1400mA / Tc= 40 C) :


~ 577 umol/sec( range 380-780 nm => estim. for 400nm range )* , while dissipating ~313 Watts of power ..
1,84 umol/J or 12H DLI of 24.9 mols ( 23,87 mols for the 400-700 range )


Less Watts than HPS ,more umols/J

(even for more narrow range ....GP 400 has the advantage of counting the umols of 100 nanometers more than CXAs )
And for sure far better light quality ...

(Relative Power spectral distribution ,normalised to '1' .
Not absolute power spectral distribution comparison)
....

And that makes up ,even if driving 4x CXA3070 at Nominal mode at 2000 mA / Tc=55C .

And though the by 'numbers',the CXAs seem to be beaten by the GP400 in such case ,
in real life ,they both perform almost equally ,gram-wise .
With the CXAs dissipating 109 Watts less ,still producing around ~300grm ...

(a pretty 'easy' score of .9-1 gpw with the CXAs ..
But an efficiency score of .75 gpw for the GP400 ..Not so easy ,but not impossible .)

CXA3070 Z4 yield efficiency scores:
HE 300-1400 mA mode : usually >1 gpw .Reported average around 1.1- 1.3 gpW .
NM 1400-2100 mA mode : Expected average around 0.8 - 1 gpw .
HO 2100-2800 mA mode : Not tested (yet) .Probably around 0.5-0.7 gpw .)