The Ideal spectrum.

[rkymtnman]

U should be good. When just the reds are on, it shines pretty dang well.

for 37 bucks it's hard to say no. think i'll order one.

 

[InTheValley]

nice, i have a gromaus puck in my cart at amazon. my area is 3x4 but not quite wall to wall plants.

so you think 1 of those pucks woudl be all i need? i was on the edge to buy 2 instead. wasn't sure how accurate teh 3x3 advertised coverage was?

 

[InTheValley]

Are you trying to mimic time of day intensity of the sun by blasting the middle 4 hours and the sunrise/sunset ramping?

Ive noticed the increase in far reds showing up in lights these days like the alibaba panels, flowing initiators and now HLG as well in the new trinity light hybrids testing.


Is that 7 watt puck enough to trigger the Phytochrome to an active state?

Yeah, pretty much what I was after. I do it manually right now, till i can get a zigbee controller. But yes, that is the premise of what Im doing. Plus, my plants, being 12/12 from seed, and in smaller containers, they dont need 50 DLI on the meter. They need way less, so during mid day, I get them 600 PAR for the 4 hours, and 400 PAR for the other 8 hours. I have beatn the heck out of my plants in the past with to much light, so I tryed to reduce it to a logical means, and they look fantastic now. Usually look horrible at this point,lol..

 

[InTheValley]

here are my plants.

Biggest was transplanted from solo cup at day 28, and left 1 in the solo to see growth difference, because i was told plants dont grow roots once they start to flower, so i transplanted and as you can see, HUGE difference.

Bigplant is 47 days from seed, 22 days in flower. ( i start my flower count on first pistil shown)
Smaller on left are 30 days from seed, 9 days flower using MegaCrop nutes, recharge 1 time a week, no CO2

 

[InTheValley]

really, at the end of the day, spectrum means nothing.

 

[ChiefRunningPhist]

Some photochemical plant responses don't scale with intensity of the WV being emitted. Just the mere fact of its presence is enough.

EDIT:
Been trying to cite the source for that info but can't find it atm, when I do I'll throw it up. I think it was from the KIS organics podcast or from one of the research papers I've been looking over but they are really long and I couldn't find that little nugget when searching just now...

 

[OneHitDone]

really, at the end of the day, spectrum means nothing.

 

[Rocket Soul]

Some photochemical plant responses don't scale with intensity of the WV being emitted. Just the mere fact of its presence is enough.

EDIT:
Been trying to cite the source for that info but can't find it atm, when I do I'll throw it up. I think it was from the KIS organics podcast or from one of the research papers I've been looking over but they are really long and I couldn't find that little nugget when searching just now...

Bumping and hoping you found that reference/citation....

 

[mr. childs]

really, at the end of the day, spectrum means nothing.

so that means it just takes a plant time to essentially get acclimated to the spectrum to produce the best results?

 

[InTheValley]

so that means it just takes a plant time to essentially get acclimated to the spectrum to produce the best results?

intensity and heat reduction, although some peaks of the spectrum intensify genetic traits and certain chemical properties in most strains, any light as long as its bright, will grow this plant.

 

[ChiefRunningPhist]

Bumping and hoping you found that reference/citation....

No I didn't ever find that reference. I gave a bit of effort that day and wasn't able to produce it. I didn't think about it again. At this point I feel bad for even posting it. I guess just be open to the possibility but atm Id view it as speculation at best till I can find the paper. Sorry

 

[Rocket Soul]

Only asking cuz i speculate the same

 

[SSGrower]

Only asking cuz i speculate the same

I agree.

 

[ChiefRunningPhist]

Haha! I knew I read it somewhere! Here you guys go..


I thought it was in a paper I read and not in a summary, but that's probably why I couldn't find it! Anyways this link is pretty good, check it out..
https://www.frontiersin.org/articles/10.3389/fpls.2019.00296/full

@SSGrower @Rocket Soul

 

[ChiefRunningPhist]

Attached are 3 digitized SPD color analyses. Action, Solar, and a 3500k CRI80 LM301H.

Most times UV is quoted as 3-4% of total solar emmision. Though within the ambiguous bounds of PAR, solar UV makes up for closer to 8% of total irradiance. (Refer to attachment, 800nm or less)

I've been seeing a new action curve, has anyone any info on it? Where it came from? The action function represented here is from the 22 crop plants that McCree studied.


EDIT:
Also, a typical 3500K LED SPD is mostly green. I've been saying we need more green and the lack of it could be leading to "LED deficiency" but it looks like with so much green, that too little green is not the issue. I still feel that different SPDs will grow plants differently, though am giving up the hypothesis that LED deficiency is from too little green. Maybe blue-ish green is lacking and causing issues, but on the whole, white LEDs have a pretty significant amount of their emission falling between 500nm & 600nm.

-3500k-
FR - 2%
R - 37%
G - 43%
B - 16%

 

[nachooo]

Attached are 3 digitized SPD color analyses. Action, Solar, and a 3500k CRI80 LM301H.

Most times UV is quoted as 3-4% of total solar emmision. Though within the ambiguous bounds of PAR, solar UV makes up for closer to 8% of total irradiance. (Refer to attachment, 800nm or less)

I've been seeing a new action curve, has anyone any info on it? Where it came from? The action function represented here is from the 22 crops that McCree monitored.


EDIT:
Also, a typical 3500K LED SPD is mostly green. I've been saying we need more green and the lack of it could be leading to "LED deficiency" but it looks like with so much green, that too little green is not the issue. I still feel that different SPDs will grow plants differently, though am giving up the hypothesis that LED deficiency is from too little green. Maybe blue-ish green is lacking and causing issues, but on the whole, white LEDs have a pretty significant amount of their emission falling between 500nm & 600nm.

-3500k-
FR - 2%
R - 37%
G - 43%
B - 16%

Great info !!! thanks

 

[wietefras]

I've been seeing a new action curve, has anyone any info on it? Where it came from?

Which one? There are a couple alternatives.

For instance the DIN 5031 curves:


Big difference is what they measure. The purple line is solely for chlorophyll. The other two for the two photosynthesis systems in leaves.

Shinji Tazawa also produced action spectrum chart which looks pretty similar to the McCree one.

 

[ChiefRunningPhist]

Which one? There are a couple alternatives.

For instance the DIN 5031 curves:
View attachment 4392434

Big difference is what they measure. The purple line is solely for chlorophyll. The other two for the two photosynthesis systems in leaves.

Shinji Tazawa also produced action spectrum chart which looks pretty similar to the McCree one.

These are the 2 action curves I was referring to. I don't know what the 2nd one is being derived from? Looks similar to the photosystem 1 spectra, but the "ambiguous action spectra" has more blue sensitivity than red contrary to the photosystem 1 spectra you posted, or any spectra for that matter..

McCree...


"Ambiguous action spectra"...

 

[lukio]

LED deficiency is from too little green.

hey chief! wondering what issues you have under led? you seem very clued up!

 

[ChiefRunningPhist]

hey chief! wondering what issues you have under led? you seem very clued up!

Lol what's up man, well first off I really don't know at all and definitely could be wrong, but imo (only opinion) It seems there's at least a slight predisposition towards slight chlorosis and symptoms that somewhat resemble Mo (or kinda like Mg) def. Blotchy leaves, stunted growth. Sometimes showing symptoms of slight Ca & K def. I fly through veg, but during bloom its a roll of the dice whether or not they exhibit symptoms. When I switched from HPS to LED I noticed a different type of growth, smaller buds, but more of them, shorter internodal distance, reduced stretching, ect, amoung other morphological differences. I think that SPD plays a big role in how a plant grows. The sun grows a plant differently than a T5, compared to a MH, compared to a HPS, ect.. They all provide photons, but the plant responds differently according to what type of photons it gets. I keep my RH at 50% but have grown the plant outdoors plenty, and in a drier natural climate than a constant 50% RH. I could just be a shit indoor grower lol, but I didn't really have these issues with HPS. I'm certain the SPDs differ in comparison, but aside from that I'm not really certain of anything. Also, it seems more LED guys jump on here with "Ca/Mg" issues, but maybe it's due to LEDs appealing to newbs more than HID does, idk? I've used GH 3part and Maxi series for RDWC and coco flood table recirc systems. Max 83F, pH held at 5.85, water temp 69, ppm max of 800.

This is what I use as a guide, but on my next round will start to swing the pH rather than keep it constant...


EDIT:
What lights do you use? Nutes? Your plants always look really good and seem to have more reds and autumn colors than I get.