Do LED (QB boards) cause less stretching & generate more frost than HPS?

Hot Diggity Sog

Well-Known Member
color temp is just one measurement and there are an infinite number of spectra that can create a given color temp

look at spectra of full sunlight, ~5500k
http://www.crslight.com/images/sun.jpg

look at spectra of a 5700K LED... its nothing at all like that
http://cobkits.com/wp-content/uploads/2017/06/1212-90-gen6-spectrum-1024x652.png


unless youre going to use some colors during veg and different ones during bloom, no point in that. they are all the same tech with different thicknesses of phosphor. for a given CRI if you take 3000k, 3500k, and 4000k and can uniformly mix them, the result is... 3500k more or less

pick a spectrum and use it, and it will be more uniform
Interesting...OK.
 

Hot Diggity Sog

Well-Known Member
Four dual-board kits would be an awful lot of light. What size is your space?
It's a bit uneven but roughly 8'x13' or so. I don't know what shape the plant will develop into but I'm thinking something like 5 or 6 feet tall and 3 or 4 feet around.
 

Hot Diggity Sog

Well-Known Member
color temp is just one measurement and there are an infinite number of spectra that can create a given color temp

look at spectra of full sunlight, ~5500k
http://www.crslight.com/images/sun.jpg

look at spectra of a 5700K LED... its nothing at all like that
http://cobkits.com/wp-content/uploads/2017/06/1212-90-gen6-spectrum-1024x652.png


unless youre going to use some colors during veg and different ones during bloom, no point in that. they are all the same tech with different thicknesses of phosphor. for a given CRI if you take 3000k, 3500k, and 4000k and can uniformly mix them, the result is... 3500k more or less

pick a spectrum and use it, and it will be more uniform
If you had to pick one spectrum to flower with using QB304's, would it be 2700K? The reason I wanted to mix spectrums was to see if the 4000K side had increased resin production. Then, did the 2700K or 3000K side produce more dense flowers. Would the parts of the plant that got an equal dose of 2 different spectrums show any differences. Would the 4000K produce too much leaf relative to the 2700K. Stuff like that.
 

CobKits

Well-Known Member
if i had to pick one spectrum to flower it would be 3500k 90 cri

i personally think the difference between 2700k to 4000k is not super dramatic. some people claim that 4000k has a big "hole" in the spectrum and isnt great for flowering but ive never seen anything to substantiate this
 
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Hot Diggity Sog

Well-Known Member
if i had to pick one spectrum to flower it would be 3500k 90 cri

i personally think the difference between 2700k to 4000k is nto super dramatic. some people claim that 4000k has a big "hole" in the spectrum and isnt great for flowering but ive never seen anything to substantiate this
Decisions, decisions...lol
Maybe I'll pickup (2) 3500K's then and that will give me a 4000K, a 3000K and two 3500's. I can get a bit crazy with lights sometimes...haha
 

Hot Diggity Sog

Well-Known Member
that was 90 cri which isnt usually available on boards. if youre constrained to 80 cri i might go for 3000k for flowering
I remember reading another post from you talking about the differences between 80 and 90 CRI but I don't recall where. Ok...thanks for all of your feedback :)
 

InTheValley

Well-Known Member
Blue drives frost, Cold night temps drives stretch, Blue minimizes stretch. If you want frost, stem split last 3 days before chop, i noticed a big difference.
 

gpsanjeev

Member
I don’t know about qb creating less stretch and more frost but my light certainly does that. I am actually doing a side by side and just entered the flowering phase. But the difference between my light and another burple led is day and night. I have barely any stretch with my good led but the burple one is making the gals really stretch.
So yes good led light definitely creates less stretch and more frost than ordinary lights. I have journal of my girls under my good led right now as well but not the plants under crappy lights. Here is a link to my previous and current grow under my good led.

https://www.rollitup.org/p/14408007/

https://www.rollitup.org/t/third-grow-4-plants-4-strains.973635/
 

Olive Drab Green

Well-Known Member
Looks good. Soil looks a little dry?? Is it some form of coco?
It is mostly a mixture of peat, coco, pumice, and perlite. I’m growing a few pure Sativas, they don’t like it too wet.

Edit: Ah, this was my last cycle. I finished this and now have ~1,000 seeds of Purple Haze/Malawi x Oldtimer’s Haze.
 

whytewidow

Well-Known Member
I use a mix of 3k and 4k F562b's strips and 4k H inFlux_L06 strips. Very little stretch even on sativa dom plants. And frost is definitely produced heavier under leds than hps. Atleast in my case it is.

These were grown under that light.
20190113_232058.jpg 20190107_204759.jpg 20190112_175429.jpg 20181226_173542.jpg


Then my other light I built is a mix of 2700k and 3000k.

Seems to yield just a tad more. But it's also a stronger light and bigger space. 120 more watts. And I have 2x2 more area.
Single rows are sammy f562b 3ks and the double row are sunboard 96 diode lm561c s6 2700k. Dont get me wrong it brings the frost really good. Also strain dependant. But I do like the H inFlux_L06 4k strips the best out of all of them.
20190121_210233.jpg 20190121_215531.jpg mir_20190102_181653.jpg mir_20190102_181627.jpg

20181231_003809.jpg
 
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