amneziaHaze
Well-Known Member
If far red was soo good why did everyone leave hps lights.
Is far red dead
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amneziaHaze
Well-Known Member
Yea from 200 diodes 10 are far red in the corners of the lamp
grotbags
Well-Known Member
?, hps lights dont have loads of far red. but they have plenty infra red.
and the reason why people left sodium behind is all about efficiency not spectrum.
amneziaHaze
Well-Known Member
Spectrum= infra red... hps has more than 30% i think
grotbags
Well-Known Member
that doesnt make any sense?.
infra red is way beyond the band of photosynthetically active radiation (PAR) that plants use to grow.
Rocket Soul
Well-Known Member
We just added far red and uva and uvb to a few trays and apparent plant health have gone up. Far red is a good way of balancing added uv since the plant reaction seems almost opposite. We will have to see what happens at weigh in and smoke test but its looking good at least half way thru flower.
grotbags
Well-Known Member
for me the benefits of far red are no longer up for debate, end of day effect, emerson effect and like rocket says using far red to counter some of the less desireable effects of uv.
BUT!... its not magic. getting the basics right (having enough PAR light (400nm-700nm), hitting VPD, getting feed strength and irrigation frequency right for your culitivar) will yeild far far far more return in quality and quantity than adding far red will.
BUT!... its not magic. getting the basics right (having enough PAR light (400nm-700nm), hitting VPD, getting feed strength and irrigation frequency right for your culitivar) will yeild far far far more return in quality and quantity than adding far red will.
amneziaHaze
Well-Known Member
Most reaserch say that uv of any kind will degrade the plants health
Rocket Soul
Well-Known Member
Id disagree slightly, while there are real dangers in just starting applying UV too fast or strong it seems to me like a more "dial in and see" approach actually increase plant health.
But i think it depends on how you do it (and with which cultivar!). Im in the lucky position to test this myself for our own cultivar.
These are the guidelines we follow:
- introduce UV slowly, starting with uv closest to par (near uv close to 400nm).
- making sure the extra spectrum youre adding is allways "sloped" just like sunshine, so more 450nm than 400nm, more 400nm than 365nm, and more UVA than UVB. We do this by having a uva channel which is weighted 2:1 400/365nm
- uvb: adding it first for short intervals, like 5mins per hour during the 4 midday hours and when you see that there arent any negative signs in plant health you push up the time of the intervals.
We are using 295nm uvb; i hear some say 285 is preferable due to the action spectrum peak around 280 but i wanted to have something a bit more idiot proof so we dont fuck up. In anycase it seems like the output on our 295s are slightly higher than the 285s so hoping this will make up for it. Also validating this: we saw a positive effect on plant stance already from day 1 of adding 5mins of uvb. Then on second day we accidentally left it on for 30 mins straight, and plants were looking a bit sad and battered.
Since we have different setups on different tables we hope to at least draw some conclusions, we current have:
3000k 80 cri white
2700k 90 cri white
2700k 90 cri white + 660 reds and uva (400+365)
4000k 80 cri + 660 reds: standard HE spectrum + uva + far red + uvb 295.
But since im just consulting im not at the grow everyday or even every week so i rely on my growbuddy.
grotbags
Well-Known Member
still doesnt make sense... i dont get what your trying to say?.
UVC definitely, UVB maybe (depends on application), UVA nope.
i think there is definitely something going on with the synergistic effect between the uv and far red ends of the spectrum, if we look at the suns spectrum it has massive amounts uvb, uva and far red, and not just the narrow "peaks" you see from grow lights it has every nanometer represented.
if you tried to add as much far red as the sun has to a "standard" led growlight without filling out uvb/uva (and blue to some extent) end of the spectrum it would be a disaster, simillary if you try to add as much uvb/uva and blue as the sun has to a "standard" led growlight without enhancing the red/far red end it would equally be a disaster. (maybe disaster is a bit strong, but i dont think you would be impressed with the growth characteristics, lol).
yet it works in nature, under the sun?, it really does look like you cant have one without the other... and until more research studys are done using "fuller" spectrums i dont think the book is firmly closed.
Grow Lights Australia
Well-Known Member
It has been a secret for too long that you need to balance both ends of the spectrum. I think the reason it has taken so long for some growers to realise this (not you Rocket) is that most LED manufacturers do not include both ends of the spectrum and so do not see the syngeries. Far red is responsible for cell expansion but blue, violet and UVA cause cell contraction. Have a look also at the phytochrome absorption spectra, especially Pfr and see where the peaks are. Have a look at what's happening over 700nm and around 400nm. Now you know why we target those zones. We very much like UVA around 400nm because it also has photosynthetic value.
Grow Lights Australia
Well-Known Member
We would agree with this. I know there is a lot of debate about what "sunlight" is because it changes a lot but sunlight is always "true" full spectrum and white phosphor LEDs are not.
amneziaHaze
Well-Known Member
i beleve that plants get damaged growing outside the same as inside if you use uv. what i am saying is with abstance of uv you could get better results.
i found a great reaserch of using uv for a couple of seconds a day, but thats mostly to fight mold.
basicly you get the same effect as a few hours a day 60% more resistance to mold, and you see the difference in leaf damange.they showed that there was almost 0 leaf damage. compared to uv that was really affected with longer exposure.used UVC
hmm i forgot what i wanted to say with infra red i think its inside the light spectrum and lamp is using almost 30% of energy generated to make it.but the plant doesnt use it. ir is known to be basically just heat.
and i saw the reaserch from grow australia but the 2 lamps used differ soo much it could be because of the lamps. if he used the same lamp and added a uv lamp then maybe but then still you would have more watts.... but you would prove that plant uses it somehow.
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Kassiopeija
Well-Known Member
"ABSTRACT
The transformation difference spectrum for phytochrome (Pr spectrum minus Pfr spectrum) in pea tissue is determined below 560 nanometers and compared with similar data on phytochrome in vitro"
"DISCUSSION
A comparison of the transformation difference spectra for phytochrome in vivo and in vitro in the red and far red regions of the spectrum shows that the two correspond fairly closely (see Fig. 2 and Ref. 9). However, in this laboratory it has been observed that the maxima in the transformation difference spectra for extracted pea and oat phytochrome fall at 665 and 725 nm (H. Rice, personal communication), while in vivo, the peaks are at 665 and 735 (Fig. 2 and Ref. 6).
Other differences in the transformation spectra appear in the region of the blue absorption band of phytochrome where the difference spectrum in vivo has a minimum that is much reduced in size and which falls at longer wave lengths compared with that in vitro. This reduction in size provides a partial explanation for the relative ineffectiveness of blue light in transforming phytochrome in vivo (14) and for the approximately 100-fold reduction of the effectiveness of blue light as compared with red light in bringing about physiological responses mediated by phytochrome (2)."
Underlining by me
From the attached:
Some Spectral Properties of Pea Phytochrome in Vivo and in Vitro
This means that the effect of light on the phytochrome photostationairy state is largely dominated by the ratio of red to farred light and the rest is not that relevant - at least, IF red and/or farred light is being present. Sometimes spectrum diagrams have been taken in vitro and now many chromophores have this tendency to display a second, more blueshifted sorret band but it is not always that this then also has a similar biological activity, most of the time, rather not.
What's also interesting is the inability of green light to affect phytochromes:
As to not "waken up" a plant during a night inspection.
Image taken out of:
Comparison of Spectral Properties of Phytochromes from Different Preparations
The transformation difference spectrum for phytochrome (Pr spectrum minus Pfr spectrum) in pea tissue is determined below 560 nanometers and compared with similar data on phytochrome in vitro"
"DISCUSSION
A comparison of the transformation difference spectra for phytochrome in vivo and in vitro in the red and far red regions of the spectrum shows that the two correspond fairly closely (see Fig. 2 and Ref. 9). However, in this laboratory it has been observed that the maxima in the transformation difference spectra for extracted pea and oat phytochrome fall at 665 and 725 nm (H. Rice, personal communication), while in vivo, the peaks are at 665 and 735 (Fig. 2 and Ref. 6).
Other differences in the transformation spectra appear in the region of the blue absorption band of phytochrome where the difference spectrum in vivo has a minimum that is much reduced in size and which falls at longer wave lengths compared with that in vitro. This reduction in size provides a partial explanation for the relative ineffectiveness of blue light in transforming phytochrome in vivo (14) and for the approximately 100-fold reduction of the effectiveness of blue light as compared with red light in bringing about physiological responses mediated by phytochrome (2)."
Underlining by me
From the attached:
Some Spectral Properties of Pea Phytochrome in Vivo and in Vitro
This means that the effect of light on the phytochrome photostationairy state is largely dominated by the ratio of red to farred light and the rest is not that relevant - at least, IF red and/or farred light is being present. Sometimes spectrum diagrams have been taken in vitro and now many chromophores have this tendency to display a second, more blueshifted sorret band but it is not always that this then also has a similar biological activity, most of the time, rather not.
What's also interesting is the inability of green light to affect phytochromes:
As to not "waken up" a plant during a night inspection.
Image taken out of:
Comparison of Spectral Properties of Phytochromes from Different Preparations
Prawn Connery
Well-Known Member
I addressed the research posted up by @Grow Lights Australia in the other thread. There have been three tests in total, all with similar results.
You are also confusing Far Red light (700-800nm) with Infra-red light (800+nm). They are not the same thing. Blame the Chinese LED manufacturers for that because they also don't seem to know the difference.
Finally, "UV" covers a HUGE spectral range, from UVC (100-280nm) to UVB (280-315nm) to UVA (315nm-400nm) and will have vastly different effects on plants at the same photon intensities, so for anyone making blanket statements about "UV", they really need to define which "UV" they are talking about.
Far Red isn't dead – far from it. And HPS is still the yield benchmark in a lot of ways. Very hard to outyield it with LEDs, but LEDs will use less power to do it.
amneziaHaze
Well-Known Member
Soo if i use 100w and get 300g with led and 100w and get 150 with hps then its very hard to outpreform it wtf? Led kills hps in every aspect even thc %
How do you calculate yeald if you dont use power? Roomsize led still wins.
Led produces more useble light.and those 3 test where made with lamps that used more usable light.if he added a led strip with uv i would say okej true.
How do you calculate yeald if you dont use power? Roomsize led still wins.
Led produces more useble light.and those 3 test where made with lamps that used more usable light.if he added a led strip with uv i would say okej true.
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Prawn Connery
Well-Known Member
Really? I consistently yeilded 3.5lb from 1200W of HPS in a 4'x4' for over a decade. What is the most yield you have produced in a 4'x4' using LED?
HPS can still rival LED for total yield per square foot, and there even situations where HPS can have an advantage, such as in colder grows. So no, LED does not "kill HPS in every aspect" – there are other metrics to consider.
I am also not saying HPS is better than LED, because the advantages of LED outweigh those of HPS, in my opinion.
Rocket Soul
Well-Known Member
AH, what is your problem with UV and people trying to get relevant info for growers by doing tests?
I know these tests arent the perfect golden scientific standard but why all the push back? Whats your investment in this?
We put uva and uvb over a tray, with a conservative program for uvb, its the healthiest weve ever seen our plants. Did you ever try any uv for yourself?
I know these tests arent the perfect golden scientific standard but why all the push back? Whats your investment in this?
We put uva and uvb over a tray, with a conservative program for uvb, its the healthiest weve ever seen our plants. Did you ever try any uv for yourself?
amneziaHaze
Well-Known Member
People selling it and convincing people that it helps but corrupt the data with other stuff. Soo they can sell a product thats snake oil