yes i wouldn’t use 5000k, 3500k already has a high enough spike in 450 imo - i am vegging and flowering under 4k at the moment and next light will be 2700k for flowering and this will become veg
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Go ahead Brother, very interested what you say to the 2700k.
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I run 3500K 80CRI with excellent results. My former partner at HLG says he’s seen impressive results from 3000K 90CRI chips.
I think anywhere in the neighborhood is going to produce well, that’s part of the advantage of broad spectrum LED.
Run LED lights grows warmer than HID ones, to encourage optimal transpiration rates.
If resin stimulation is desired, don’t try to split the difference with more blue or higher Kelvin chips; by far the most efficient and effective approach is to use UV T5 lamps. You don’t need much.
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yes i checked my boards today before lights came on and i actually have all 3500k boards. i’ve seen some good comparisons between 80 and 90 cri. samsung 90cri goes up to S3 for lower ccts and S2 only for the higher ccts. i can only imagine how great they would perform at same bin as 80cri (S6)
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I agree with the full spectrum. And I also agree with you @Ttystikk about the 90CRI chips give that broader spectrum in the 3000K - 3500K range (I personally like the LM561c 3500K@CRI90 spectrum)
The thing is tho you do loose some lm/W with the higher CRI. The luminous flux is several points lower for the same temperature but different CRIs.
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it’s because of the lower bin - if you compared same cct and same bins they would be same output. once they have 90cri S5 or S6 it will be amazing
It’s also because of the lower CCT. Higher CCT translates to higher lumens- but lumens are for humans. Plants prefer PAR.
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new episode
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Until they produce the CRI 90 chips using S4, S5, S6, or S7 (yes they use S7 on there CRI 70 chips). We will have to decide to have a slightly wider full spectrum with slightly lower lumen output or slightly narrower full spectrum with a higher lumen output
yes only in 1 or 2 CCT have S7 though i believe, but a side by side grow of 80CRI and 90CRI showed bigger yields and growth on the 90CRI side. not sure if they were same pheno/clones or from seed though so not sure how scientific it was. but several people who compared stated they preferred 90CRI. so if S3 can beat an 80CRI S6, i hope the higher bin 90s come soon 
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I’m right there with ya @legalcanada 
I want the most bang for the buck too. However the next light I build will be with 3500K @ CRI 90 (I’ll take the lumen hit as I can always add more lights, unless they make the CRI90’s with S6 or S7)
Here is the CRI 70 info…
ah thank you, i’ve had this page open in a tab for 2 days already, i barely glanced at the 70s tho
i believe HLG has some 90cri quantum boards
i just realized the HLG canada website is up. all they have listed are the HLG 550s - 515 watt fixtures for $1500 canadian … fucking insane. i think after @Ttystikk cashed out they took grand master level on as a partner and gave him the canadian market. i better still be able to buy DIY components from the states otherwise i’ll have to shop around
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More than anything else, Steve is a good friend and a straight shooter.
HLG it’s going to be at the Seed to Sale show in Denver this month. I’m looking forward to meeting up with them and doing some catching up.
Y’all let me know what you would ask HLG if you had a face to face and I’ll make sure I come back with some answers!
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My biggest question would be why aren’t they ramping up supply to meet demand, it seems they are shooting their self in the foot by not keeping product in stock.
I’ve got a ? On Samsung LM561c charts i’ve seen the efficiency drops to 1.6 mmole per wat after 200 ma. Is that still true even with a heatsink or does it negate that effect somewhat?
They had a long supply chain, reaching back to come. They’ve just found a domestic manufacturer here in the States who will help them reduce their lead times.
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Ok, so this is a basic characteristic of LED lighting; they get less efficient as current increases. Therefore, running them softly gets you better efficiency than running them at their maximum rating.
Ya get that bud. I didn’t make it very clear. For example the next light mini overdrives the diodes way past the 2 ma mark but still claim 1.7 mmole per wat rating. They’d need something close to 820 diodes for that (according to Samsung’s chart). Can they do that bc of heatsinks or what?