The Ideal spectrum.

[hybridway2]

Really, where's you experience ?

[QUOTE="lukio, post:

"Ive never run just HPS so its difficult tocompare for me."

Nuff said.

Im yeah, why do you think i speak on these things. Experience. Many here have seen my HPS room prior to going full led. 220v seperate 100amp service, x3 mechanical timers, 7200-8600w depending. Hps, Mh, & T-5.
Average grow was 12 , 1# plants. 12'x9' of Canopy. 7 gall. Potts, 1.5-2 mo. Veg.
I personally try to only speak on things i have experienced, or are experiencing.

 

[Growgrowgadget]

Is this any good for a 80cm x 80cm x 160cm tent

 

[hybridway2]

I wonder how much UV is affecting LST?

"
Below 400 nm, there is the risk of photooxidation that generates toxic radicals, which can destroy the cell’s chlorophyll and other cellular components. Under intense UV radiation, violaxanthin (which is involved in photosynthesis) is converted via the xanthophyll cycle into zeaxanthin. In doing so, it receives excess energy from chlolorphyll and releases it as heat. This process thereby offers the plant photoprotection.
"
https://lightinganalysts.com/photometry-and-photosynthesis/

Big Ups to you for mentioning & trying to figure this stuff out. Lmk if i can assist.

 

[Warpedpassage]

And my youtube channel. https://www.youtube.com/channel/UCn6OTRh8Vkc35tJNgPpNRWA

Nice to see u posting again.
I think u are one of few people around here that have completed runs under different spectrums setups.
I see you are running 3k plus supplements, i think you have also run different combinations of just whites without supplements.
Are you finding differences in terpene production, final weight, plant structure from you different setups? I understand it may be too early for any final findings, but what do u think?

 

[jarvild]

Nice to see u posting again.
I think u are one of few people around here that have completed runs under different spectrums setups.
I see you are running 3k plus supplements, i think you have also run different combinations of just whites without supplements.
Are you finding differences in terpene production, final weight, plant structure from you different setups? I understand it may be too early for any final findings, but what do u think?

If any there vary slight, at least not enough for my personal nose to distinguish without lab testing. Personal experience tells me the best terpene profiles happen when you don't fry your plant with to much light or heat in the last 2 weeks of flower.
Now if you where about plant and bud structure then I would say yes to the different spectrum's making a difference.

 

[jarvild]

Im yeah, why do you think i speak on these things. Experience. Many here have seen my HPS room prior to going full led. 220v seperate 100amp service, x3 mechanical timers, 7200-8600w depending. Hps, Mh, & T-5.
Average grow was 12 , 1# plants. 12'x9' of Canopy. 7 gall. Potts, 1.5-2 mo. Veg.
I personally try to only speak on things i have experienced, or are experiencing.

Ok, then that post was your reply to lukio, so what did I miss.
If your HPS plant are 10 degrees above ambient then your lights are to close or your flooding the area with too much light.
Give me 7,000 watts to play with and I'll make both of us 60+K a year. I make over 30K running less than 2K for total power consumption in my grow now.

 

[hybridway2]

Ok, then that post was your reply to lukio, so what did I miss.
If your HPS plant are 10 degrees above ambient then your lights are to close or your flooding the area with too much light.
Give me 7,000 watts to play with and I'll make both of us 60+K a year. I make over 30K running less than 2K for total power consumption in my grow now.

30k a grow or a year? Lol!

 

[OneHitDone]

Word I was trying to rule out some variables. If the plants were grown under different lights but are measuring the same leaf surface temps, then I could assume either the temp probe was less than precise, or that his environment was so well managed that even the amount of IR that HPS gives off was not going to change his LST. If the measurements were NOT the same, then I'd know to look into the NIR absorption ranges of plants. Look to see if the 850nm should be absorbed or reflected. If it's absorbed try to determine how much LED power is needed to affect LST, and if it's reflected, well then.. If the measurements were the same, I'd not be able to deduce much as it could be incredible enviro mgmt or a faulty IR gun.

Most of the energy being emmitted by 850 nm LED is non visible but whether we can see the light or not means nothing to how well a plant is going to absorb the energy. Idk how efficient the chips are, but if they are 50% efficient at producing 850nm radiation, and he was running 15W, then I'd imagine if the plant were absorbing 7.5W of energy that you'd see a difference in LST.

I personally call bs on a lot of the theory I read around here about leaf surface temp.
I had shared this somewhere before and it was kinda brushed off, you seem to have the knowledge to incorporate this info into your data set in some capacity.
This was on a sunny day approximately 70 degrees.
Leaf surface temp followed by soil temp at the bark below the plant.

 

[sethimus]

what exactly is bullshit about it? and what exactly has leaf surface temperature of an actively cooled object to do with soil surface temperature, which is one large thermal mass which is NOT actively cooled by itself?

 

[jarvild]

30k a grow or a year? Lol!

Add it up. 5k flower 2k veg, lets say an average 2.5 units per thousand @ $1,600 a lb. That $20k per grow on a 3 month cycle, 4 cycles a year.
Surely you can do the math?
I want you to be successful in your endeavor.

 

[sethimus]

you only get 1,6k per pound?

 

[OneHitDone]

you only get 1,6k per pound?

Welcome to the new reality of cannabis legalization

 

[sethimus]

that‘s less than what you get for moldy shit weed around here...

 

[nachooo]

Welcome to the new reality of cannabis legalization

1500 euros per 0,5 kg.. more or less the same that cannabis clubs pay growers in Spain..These prizes are making growers not bother about quality...

 

[verticalgrow]

Is this any good for a 80cm x 80cm x 160cm tent

Great for growing Lettuce

 

[jarvild]

you only get 1,6k per pound?

No, that was just a generalization between high and low prices depending on your region. I'm higher than that at $2400 per unit.

 

[jarvild]

that‘s less than what you get for moldy shit weed around here...

I wouldn't know, I haven't bought weed in decades.

 

[jarvild]

I personally call bs on a lot of the theory I read around here about leaf surface temp.
I had shared this somewhere before and it was kinda brushed off, you seem to have the knowledge to incorporate this info into your data set in some capacity.
This was on a sunny day approximately 70 degrees.
Leaf surface temp followed by soil temp at the bark below the plant.

View attachment 4395229 View attachment 4395230

Pull some of that mulch back and give us a root zone temp.

 

[mauricem00]

If we see that the various photoreceptors are at work creating the Mcree curve it would not be difficult to explain the shape which is a mix of symmetry and asymmetry. The 580-680 range of the Mcree curve isn't exactly smooth, but the relative deviation is minor, even for the 660-680 range though it does poke out a little bit. Beyond that it falls back in line. There's also an odd linear region between 475 and 525.

If we superimpose a random plant photoreceptor response graph onto the Mcree curve we get some interesting results. I'm not suggesting either of the two data sets are perfect for a particular plant, but to some degree they should be close right?

This might suggest that all other things being equal it would be useful to target a handful of wavelengths. The individual receptor response curves explain the Emerson effect. Since LED contains almost no 400nm light there's especially good reason to add light in the 660-690 region, 675 specifically so chlorophyll A is active. There are also 4 phosphor curves in the pic, 4000K 80CRI, 4000K 70CRI, 3000K 70CRI and 2700K 80CRI. The 4K SPDs ave been compressed so the 400-500nm band is in the 10-12% range. The other two samples were compressed at the same ratio for comparison but might benefit from some additional blue.

For a simple 2 part solution (cob+660) I would probably go with 5000K 70CRI or 6500K 80CRI. Those SPDs would have been more difficult to carve out of their respective graphs so I haven't added them. I think 4000K 70CRI would work well enough using 660nm to lower the K to 3000. If we use 660nm light to lower the 3000K sample to 2700K that would provide about 5% blue, which is similar to traditional HPS spectrums.

Another approach would be to target specific colors and improve on red/blue, which might prove to be more efficacious if done in the correct ratios. The target wavelengths, going by the chart below would be 400 (or 675), 440, 575 and 625. I would hesitate to guess on the desired ratios. I'm also not clear on why chlorophyll A is showing a stronger 400nm response as an individual photoreceptor when it seems to create more photosynthesis in the Mcree curve at 675, or whether 400nm light would invoke the Emerson effect the same as 675nm light does. Any ideas or consideration on the subject?

View attachment 4248849 .

the mcree curve only measures CO2 production in response to light but this is only one thing plants use light for.plants have close to 400 pigments that perform many functions. some we still don't understand.the best light for plant growth is sunlight and the absorption spectrum shows that plant use everything fro 300nm to 700nm. it should be noted that the Emerson effect disappears when plant receive enough violet light (430-440 nm) only CMH and T5s can come close to natural sunlight. I have been a P.U MMJ T5 closet growers for 6 years and am happy with my results. for a larger grow I would use a CMH light. this site is entertaining but you should do your own research

 

[OneHitDone]

Pull some of that mulch back and give us a root zone temp.

It's a different day at a different time now.
But those photo's demonstrate that the suns radiation does not have the direct effect on leaf surface temp as it does on surrounding objects.
Clearly the plant has a built in cooling mechanism.