The far red thread

Airwalker16

Well-Known Member
Well guys. After a SHIT LOAD of work and a lot of burns on my fingers, alas it is complete! Woot! Mounts right onto my current diy and can be taken off anytime.
This shit better have been worth it.... got my water chiller today too. Yay
I'll take another pic later at lights off.20160426_100847.jpg 20160426_101944.jpg 20160426_101953.jpg
 

Zulunature

Well-Known Member
I feel like this thread is dead.
Nah it's not dead, I've been reading the posts, glad to see you finally have the 730nm emitters up and running finally. I still haven't gotten started on the build for mine yet so you're going well.

I assume you'll run these for 10-15 minutes at lights out, I plan to overlap by a few minutes so they will come on a couple of minutes before lights out.

Anyway well done they look good.

PS do you plan on doing some uvb leds or going reptile path?
 

Airwalker16

Well-Known Member
Nah it's not dead, I've been reading the posts, glad to see you finally have the 730nm emitters up and running finally. I still haven't gotten started on the build for mine yet so you're going well.

I assume you'll run these for 10-15 minutes at lights out, I plan to overlap by a few minutes so they will come on a couple of minutes before lights out.

Anyway well done they look good.

PS do you plan on doing some uvb leds or going reptile path?
Neither.
http://www.htgsupply.com/products/agromax-4-foot-t5-pure-uv-bulb
This is what I plan on if I do supplement uvb. I'd use it for 15 mins a day for 6-9 of middle hours of 12.
 
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BobCajun

Well-Known Member
I have a theory that blue light acts the same way as far red for end of day treatments. This article mentions that the photoreceptors involved absorb light over 700 nm and below 500 nm. I read other pages with similar things where blue acted the same as FR, though none directly using blue for end of day flower promoting. It was always something where either blue or FR inhibited flowering. But they were still acting in the same way. It was mentioned that it took 30 minutes for blue to reverse 5 minutes of red in one article. Since I'm using incandescent blacklights as a FR source and they also put out UVA, centered at 400 nm, I have increased my treatment time from 5 minutes to 30, just to make sure I get the most out of that 400 nm light along with the FR. Also, since blue and FR seem to be the same, maybe pure FR treatments should also be 30 minutes to get full benefits.
 

Airwalker16

Well-Known Member
I have a theory that blue light acts the same way as far red for end of day treatments. This article mentions that the photoreceptors involved absorb light over 700 nm and below 500 nm. I read other pages with similar things where blue acted the same as FR, though none directly using blue for end of day flower promoting. It was always something where either blue or FR inhibited flowering. But they were still acting in the same way. It was mentioned that it took 30 minutes for blue to reverse 5 minutes of red in one article. Since I'm using incandescent blacklights as a FR source and they also put out UVA, centered at 400 nm, I have increased my treatment time from 5 minutes to 30, just to make sure I get the most out of that 400 nm light along with the FR. Also, since blue and FR seem to be the same, maybe pure FR treatments should also be 30 minutes to get full benefits.
Interesting.
 

PurpleBuz

Well-Known Member
I have a theory that blue light acts the same way as far red for end of day treatments. This article mentions that the photoreceptors involved absorb light over 700 nm and below 500 nm. I read other pages with similar things where blue acted the same as FR, though none directly using blue for end of day flower promoting. It was always something where either blue or FR inhibited flowering. But they were still acting in the same way. It was mentioned that it took 30 minutes for blue to reverse 5 minutes of red in one article. Since I'm using incandescent blacklights as a FR source and they also put out UVA, centered at 400 nm, I have increased my treatment time from 5 minutes to 30, just to make sure I get the most out of that 400 nm light along with the FR. Also, since blue and FR seem to be the same, maybe pure FR treatments should also be 30 minutes to get full benefits.
The diffs in the Pr and Pfr absorption spectrums allow short day plants to detect sunset because thats what happens to red vs far red light as the sun goes down. Blue light at the other end doesn't have the same effect. As sunset approaches uva light fades before any red light. if uva light does effect flowering period its most likely to interrupt flowering, acting as a "daytime signal".

but what this means for your unconventional source of far red + uva I have no clue, but I wouldn't use it.
 

VegasWinner

Well-Known Member
I have a theory that blue light acts the same way as far red for end of day treatments. This article mentions that the photoreceptors involved absorb light over 700 nm and below 500 nm. I read other pages with similar things where blue acted the same as FR, though none directly using blue for end of day flower promoting. It was always something where either blue or FR inhibited flowering. But they were still acting in the same way. It was mentioned that it took 30 minutes for blue to reverse 5 minutes of red in one article. Since I'm using incandescent blacklights as a FR source and they also put out UVA, centered at 400 nm, I have increased my treatment time from 5 minutes to 30, just to make sure I get the most out of that 400 nm light along with the FR. Also, since blue and FR seem to be the same, maybe pure FR treatments should also be 30 minutes to get full benefits.
I have found great growth during vegetative stage with royal blue led's. Works great and I have far red set up for next phase. peace. Plan on adding some IR red too with the Far red. They also have deep red led's. nice mix perhaps. peace
 

BobCajun

Well-Known Member
The diffs in the Pr and Pfr absorption spectrums allow short day plants to detect sunset because thats what happens to red vs far red light as the sun goes down. Blue light at the other end doesn't have the same effect. As sunset approaches uva light fades before any red light. if uva light does effect flowering period its most likely to interrupt flowering, acting as a "daytime signal".

but what this means for your unconventional source of far red + uva I have no clue, but I wouldn't use it.
Nonetheless, it might just work. Somebody would have to test it with pure blue LEDs. From the absorption spectra shown in that graph guod posted you can see that Pfr absorbs blue about half as much as FR. So I guess you'd need twice as much wattage or time with the blue for the same effect. May explain why it takes 30 minutes with blue. But the the Pr also has absorption in the blue range, which seems odd. Maybe only the parts that are not shared are effective at manipulating flowering. Anyway, something to think about. The incandescent blacklight puts out a lot more FR than 400nm so I'm covered either way. Whether the 400 nm part actually does anything, no way to know. May prevent the stretching effect of the FR, blue light being known to produce short stalks.
 
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PurpleBuz

Well-Known Member
Nonetheless, it might just work. Somebody would have to test it with pure blue LEDs. From the absorption spectra shown in that graph guod posted you can see that Pfr absorbs blue about half as much as FR. So I guess you'd need twice as much wattage or time with the blue for the same effect. May explain why it takes 30 minutes with blue. Anyway, something to think about. The incandescent blacklight puts out a lot more FR than 400nm so I'm covered either way. Whether the 400 nm part actually does anything, no way to know. May prevent the stretching effect of the FR, blue light being known to produce short stalks.
Doesn't work that way, using absorption your only looking at half of the picture. The whole point of using Pr/Pfr is to duplicate a known day length signal that is present during sunset, that occurs in nature.

Did you know that if you flash 730nm in the middle of the dark period that it will inhibit flowering ?

Did you know that if you shine royal blue (440nm) during the night that it will inhibit flowering ?

Did you notice that there isn't ANY literature stating to use UVA as a flowering trigger ?

The overlap between the Pr and the Pfr at 400nm is not distinct like it is for the diff between Pr and Pfr at 660/730nm. Note how Pr absorption drops like a cliff between 660 and 730nm.

all that said its possible that the UVA intensity that your giving is low enough that its doesn't matter, or perhaps your unconventional source isn't doing anything except to lengthen your daylength (ie no effect).
 

Airwalker16

Well-Known Member
Doesn't work that way, using absorption your only looking at half of the picture. The whole point of using Pr/Pfr is to duplicate a known day length signal that is present during sunset, that occurs in nature.

Did you know that if you flash 730nm in the middle of the dark period that it will inhibit flowering ?

Did you know that if you shine royal blue (440nm) during the night that it will inhibit flowering ?

Did you notice that there isn't ANY literature stating to use UVA as a flowering trigger ?

The overlap between the Pr and the Pfr at 400nm is not distinct like it is for the diff between Pr and Pfr at 660/730nm. Note how Pr absorption drops like a cliff between 660 and 730nm.

all that said its possible that the UVA intensity that your giving is low enough that its doesn't matter, or perhaps your unconventional source isn't doing anything except to lengthen your daylength (ie no effect).
You say flashING it at 6 hours or so in will slow flowering? But not using it right at the end for 15 mins or so?
 

BobCajun

Well-Known Member
Doesn't work that way, using absorption your only looking at half of the picture. The whole point of using Pr/Pfr is to duplicate a known day length signal that is present during sunset, that occurs in nature.

Did you know that if you flash 730nm in the middle of the dark period that it will inhibit flowering ?

Did you know that if you shine royal blue (440nm) during the night that it will inhibit flowering ?

Did you notice that there isn't ANY literature stating to use UVA as a flowering trigger ?

The overlap between the Pr and the Pfr at 400nm is not distinct like it is for the diff between Pr and Pfr at 660/730nm. Note how Pr absorption drops like a cliff between 660 and 730nm.

all that said its possible that the UVA intensity that your giving is low enough that its doesn't matter, or perhaps your unconventional source isn't doing anything except to lengthen your daylength (ie no effect).
Not exactly right, but close. Far red in the middle of the dark period has no inhibiting effect on short day plants flowering, however red light does. In fact, if you use a far red flash after a red flash it will cancel out the red flash's inhibiting effect completely. Also I'm pretty sure blue light does not inhibit flowering either. Far as I know, only red does. You'd have to link some sources.
 

PurpleBuz

Well-Known Member
Not exactly right, but close. Far red in the middle of the dark period has no inhibiting effect on short day plants flowering, however red light does. In fact, if you use a far red flash after a red flash it will cancel out the red flash's inhibiting effect completely. Also I'm pretty sure blue light does not inhibit flowering either. Far as I know, only red does. You'd have to link some sources.
actually far red does I have seen test results like that back in my college days. don't have time to hunt down the research for you. the blue light tests I have seen on rollitup about a year or two ago.
 

BobCajun

Well-Known Member
actually far red does I have seen test results like that back in my college days. don't have time to hunt down the research for you. the blue light tests I have seen on rollitup about a year or two ago.
Here, read up on photoperiodism and get back to me. Here's a quote;

The behavior of phytochrome provided the first model — called the hourglass model — of the mechanism of photoperiodism in short-day plants.
  • Sunlight is richer in red (660 nm) than far-red (730 nm) light, so at sundown all the phytochrome is PFR.
  • During the night, the PFR converts back to PR.
  • The PR form is needed for the release of the flowering signal.
  • Therefore, the cocklebur needs 8.5 hours of darkness in which to
    • convert all the PFR present at sundown into PR
    • carry out the supplementary reactions leading to the release of the flowering signal ("florigen").
  • If this process is interrupted by a flash of 660-nm light, the PR is immediately reconverted to PFR and the night's work is undone (C)
  • A subsequent exposure to far-red (730 nm) light converts the pigment back to PR and the steps leading to the release of "florigen" can be completed (D)
  • Exposure to intense far-red light at the beginning of the night sets the clock ahead about 2 hours or so by eliminating the need for the spontaneous conversion of PFR to PR
 
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