The far red thread

draz said:
That is my plan, just waiting on parts to set it up though.
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Somebody asked me about this, after I set them up with instructions to build the LED side....I don't think there is any deviation from just full runs instead of perpetual...only Captain seems to deviate slightly from 12/12...

I am waiting too...got a few on the way :peace:
 
I finally got my act together and built my flowering bar. Its a 3 foot 1.5" wide heat sink with two circuits on it.

Circuit 1 - deep red 660 + UVA leds.
Circuit 2 - 4 far red 730 nm 20 mm stars evenly spaced. nice even distribution throughout the room.
on a separate timer runs 15 minutes before and after lights on and at lights off. Mimics sunset and sunrise.

I started running the flowering bar after the initial stretch surge. room is running at 12/12.

Observations so far: (its been over 30 days).

The entire room of mixed strains is maturing fast, maybe a week ahead of expected. Some may have to do with the heat wave we had on the west coast for June and early July,

I have a couple of Golden Tiger phenos, (14 weekers) that I usually have issues getting the flowers to bulk up and have the "sativa keep on growing syndrome". well the flowers are bulking up, so I am really happy, Looks like the new veg growth is slowing down, to be confirmed in a few weeks.
 
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I have made several led fixtures for supplemental lighting and slowing switching out all of my T5s for cobs in veg. There is no comparison, crazy tight node spacing and fast growth, even with the el cheapo cool white eBay cobs mixed with veros. The T5s might go in my garage or garbage. Ha!
Anyway, I'm working on a flowing fixture that will use a combination of whites, reds and blues, mostly white cobs.
The room has HPs overheads and one vertical in the center. I do trees in a diy undercurrent system. Big lady's with biiiiig flowers. Using meanwell Ldd drivers on a coralux board with timmed dimming done with an arduino for my newest addition. I have some 3w far reds I purchased on a whim and also IR that are 840nm that I planned on coming on for 30 min after the main lights go out. I have have read conflicting info on using 840 IR since the purchase.
Is this wavelength worth throwing in the mix? Waste of time?
Thanks!
 
Meinolf said:
In my opinion, 840nm is a waste, because the Pfr absorption peaks at 730nm. http://publishing.cdlib.org/ucpressebooks/data/13030/n2/ft796nb4n2/figures/ft796nb4n2_00082.gif

I would neither use 730 in the morning nor for the whole time. For me the only point about 730 is tricking the plants photoperiodism by phytochrome manipulation
http://users.rcn.com/jkimball.ma.ultranet/BiologyPages/P/Photoperiodism.html
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Thanks! I'll just leave the 730s off the bars for now until I get more and another bar for the end of day experiments. And the IRs? Maybe I'll use them for a security camera or something?? Ha!
Thanks!
 
Meinolf said:
In my opinion, 840nm is a waste, because the Pfr absorption peaks at 730nm. http://publishing.cdlib.org/ucpressebooks/data/13030/n2/ft796nb4n2/figures/ft796nb4n2_00082.gif

I would neither use 730 in the morning nor for the whole time. For me the only point about 730 is tricking the plants photoperiodism by phytochrome manipulation
http://users.rcn.com/jkimball.ma.ultranet/BiologyPages/P/Photoperiodism.html
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if you review enough short day plant flowering studies you will find that far red light applied after a short dark period will effect flowering negatively if the dark period isn't long enough. It isn't as simple as just Pfr balance, emulating sunrise as well as sunset is the same thing that would happen outdoors at dawn and dusk. since my cost\effort is trivial once setup for dusk, I choose to emulate normal sunrise\sunset.

and oh btw we aren't tricking the plants, we are emulating their natural env, since some of the normal environmental signals are missing when growing indoors.
 
So what's your take on far red and infared? I have fantastic results with just good old 12/12 with light crammed all around the plant like a Christmass tree. No shadows. Led, HPS, floros whatever, its always the same effect with color temp no matter the source, just so its not cooking them .... 5000-6400 veg.. 4000-27??ish For after stretch in flower. Roots in 18 gallon totes. DIY undercurrent with a bit of misting on upper roots.
I'm just starting to dabble with different lighting spectrums.
 
The Pfr (plant is "awake") is generated by 660nm light, something that is prevalent in almost every grow light source (at least it should be). If the light is on, the plant grows. Whereas Pr is generated fast (plant is set to "sleep") by 730nm light, something that isn't there at all when the main LED are shut off. [ I'm under the suspicion, however, that using HPS bulbs with their after dark glow has unknowingly benefitted flowering under them. ]

I wouldn't argue there a certain rhytms in the plant (as stated in that link about photoperiodism above), but I strongly doubt emulating a sunrise affects our desired results in any way. You're right that there isn't much effort to set a second schedule. I still wouln't want to light the 730s any more time than necessary due to their poor efficiency.
 
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Meinolf said:
The Pfr (plant is "awake") is generated by 660nm light, something that is prevalent in almost every grow light source (at least it should be). If the light is on, the plant grows. Whereas Pr is generated fast (plant is set to "sleep") by 730nm light, something that isn't there at all when the main LED are shut off. [ I'm under the impression, however, that using HPS bulbs with their after dark glow has unknowingly benefitted flowering under them. ]

I wouldn't argue there a certain rhytms in the plant (as stated in that link about photoperiodism above), but I strongly doubt emulating a sunrise affects our desired results in any way. You're right that there isn't much effort to set a second schedule. I still wouln't want to light the 730s any more time than necessary due to their poor efficiency.
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really? On one bar it takes about 4 leds x 2.5 V at 550 ma for 30 minutes. That sure is a whole lot of relative wattage. and your worried about efficiency ? ha!

One of your problems is that you are interpreting as 660 as awake and 730 as go to sleep. That's wrong, its MUCH more complicated than that as the experiments with flashing 730 nm AFTER a period of dark actually stops flowering similar to a flash of 660 nm part way through the dark cycle.,
 
PurpleBuz said:
really? On one bar it takes about 4 leds x 2.5 V at 550 ma for 30 minutes. That sure is a whole lot of relative wattage. and your worried about efficiency ? ha!

One of your problems is that you are interpreting as 660 as awake and 730 as go to sleep. That's wrong, its MUCH more complicated than that as the experiments with flashing 730 nm AFTER a period of dark actually stops flowering similar to a flash of 660 nm part way through the dark cycle.,
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As I said, you're right it's no big deal. But, being cynical, that also goes for doing a 360 jump everytime you open the tent. What purpose do you think this sunrise emulation serves? Besides, I was rather referring to people having the 730s on the whole day. If this turned out to be enhancing something (e.g. swell after stretch), I'd also look for efficient alternatives. I'm open to info about swell lighting setups, but I believe it's hard to find empirical evidence on that due to our well known error margin.

I'd also be interested in those mentioned studies that show negative effects of "lights out, 730 on, 730 off, lights on" during the day. Just this afternoon I showed the 730 lights to a friend ("Woa, seems like I have an insect's vision or something"), doing exactly that. Do you think that had a negative effect, if so, on what? To me that would be totally counter-intuitive, because to my scientific standards flowering our plants is not about the light of the day, but rather about the dark of the night. Plants get temporarily shaded at daytime by all kinds of incidents in nature.
 
at the very least sunrise emulation provides the normal environmental signals that an outdoor plant is sensitive to. afaik there are no scientific tests that show both sunrise and sunset emulation is better than providing just sunset.

BUT if it works my stubborn landrace sativas may be more manageable indoors.

Efficient alternatves ? did you actually do the math to see how much time and pennies the cost is ?

btw I actually want to provide a tiny amount of far red light during the day, but am wary of excessive stretch.
 
PurpleBuz said:
at the very least sunrise emulation provides the normal environmental signals that an outdoor plant is sensitive to. afaik there are no scientific tests that show both sunrise and sunset emulation is better than providing just sunset.

BUT if it works my stubborn landrace sativas may be more manageable indoors.

Efficient alternatves ? did you actually do the math to see how much time and pennies the cost is ?

btw I actually want to provide a tiny amount of far red light during the day, but am wary of excessive stretch.
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It's not about a romantic sunset, it's about that very clear and distinct goal of converting the Pfr to Pr instantaneously, because research indicates that this operation reduces the critical night length for flowering in short-day plants, which can presumably be utilized for shorter growing periods and/or higher yields. For me it is just unclear what the FR treatment in the morning is doing after all. Just because the twilight effect is happening at dusk AND dawn in natural reality it doesn't necessarily mean it is beneficial in any case. The same goes for natural things like clouds, rain, hail, insects or similar natural dangers.

I'm curious about your stretch experiment.
 
I thought I'd share my flower initiator project that I completed tonight. The project included a 12v timer relay from Amazon ($6), 3 - 720nm Far Red Cree XTE leds and 1 Meanwell LD-700HW from Rapid LED ($20), and a 3'x2" aluminum strip from Lowes ($12) to mount the LEDs on using thermal adhesive.I had the project box, wire, and 12v wallwart. The aluminum strip with the 3 Far Red LEDs is hanging from the ceiling of my flowering cabinet from some wire and magnets. The 12v wallwart powers the timer and the LEDs, which will come on for 8 minutes immediately after lights out. Here's a few pics - the Meanwell driver is wired inside the project box with the timer.

DSCN2682.JPG DSCN2706.JPG DSCN2708.JPG
 
I can verify that captainmorgan's 730 schedule (12/12 for 2 weeks, 13.5/11.5 for 4 weeks, 12/12 for 2-3 weeks with 730 for 10 minutes after lights-out) reduces the overall time significantly. 10 week strains finished in 9 weeks, 9 week strains were slightly overdue. Very low intensity was used (2x 5W per 1.3m²). I believe the use of this technology will be regarded as a standard procedure quite soon.
 
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