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Far red leds (730 nm)?

L

Lysrgic

New member
Hi all. Soon I'll Finnish my new light system including 6 X Cxb35900 (3500k) with a liquid cooling system and was wondering if with this system, the plants are getting everything they need, or if maybe I have a week link in my light system? (1.2x1.2m grow tent)

I was reading in some forums that adding some far red less that will be turned on for 5-10 min after lights off, will ultimately give me more yield.

Now I'm not an expert, but I figured that the chin ease star led are pretty cheap, so maybe it worth the extra effort? Does any one have any experience or opinion on this method? Thx
 
jikko77

jikko77

Active member
did you added just the 730 nm led?
any uv?
anything else bwtween 700 and 730 nm?

far red have some other use, not only pr pfr change.
what i've found so far:

jikko77 said:
regarding the far red/ir ecc ecc:
the pigment related to this is the fitocromo (?), it change, according to different external input from pr to pfr (the peak is about 660nm and 730 nm)
limit the strench of the hypocotyl; provoke the antocianine(?) action; expand the colitedoni(?); a photoperiodic controll in the flowering stage.
Click to expand...

(?) mean i don't know/ have found the traslation in english.

some where else i did read something on the shadow and the uses of far red to limit leaf covering other leaf plant, but it was rather a chit chat than a sci fi text.
 
A

AvidLerner

Member
I use the Far Red leds 15-3w in a 2x2 for 45 minutes after lights out. works great. I see a shorter growing schedule by maybe 5 days. I also use Deep Red and IR all day for good thc development and strength. I use royal blue 12/12 aolong with cob 12/12 off cycles of each other 12 hours cob and then 12 hours royal blue, for veg to make close nodal growth and strong roots and stems. peace
 
A

AvidLerner

Member
jikko77 said:
did you added just the 730 nm led?
any uv?
anything else bwtween 700 and 730 nm?

far red have some other use, not only pr pfr change.
what i've found so far:



(?) mean i don't know/ have found the traslation in english.

some where else i did read something on the shadow and the uses of far red to limit leaf covering other leaf plant, but it was rather a chit chat than a sci fi text.
Click to expand...

I use Deep red all day along with IR. I leave the UV-B alone as it is not cost effective. the IR helps out for the lack of UV-B, I think. peace
 
L

Lysrgic

New member
cheers guys' thx for the answers!

so after ridding carefully all your posts and doing a bit of a research (a good old post if anyone interested: https://www.icmag.com/ic/showthread.php?threadid=293711).

my main findings are:

1. far red light (660nm and 730nm for 20-30 min) before and after regular lights are on, will enhance plant growth and leaf size. - only at the flowering stage

2. when using cobs, you need to add far red threw the lightning cycle, since leds dont produce far red them self (730nm only). hps do produce this wavelengths

3.there are two different ratios of nm amount for far red lights during the worktime of the cobs, and after. now, the ratio for when the cob is on, is 1 to 4. and after cob goes off you should raise the amount of far red nm by 15-25% (for 10-15 min, and another 10-15 min before next cycle).

Now, first of all I just want to make sure im right and not writing just crap.

Second of all, If im using 6 cxb3590 with HLG240H-C1050B, how many WATS of far red will i need? any suggestion on a specific led or any Chinese manufacture on ebay will do the work?

thank for all the help
 
jikko77

jikko77

Active member
i do know osram have a multiband far red starting from 700 to 730 nm, or at least i do remeber something like that.

and this is totaly imho: a mix of 3000°k and 5000°k (90cri and 80cri) would cover the par spectrum better than just a single 3000, 4000 and even 5000°k, leaving out just the 700nm pick.

this is a 3070 5000°k:



source: cutter.au

AvidLerner said:
I use Deep red all day along with IR. I leave the UV-B alone as it is not cost effective. the IR helps out for the lack of UV-B, I think. peace
Click to expand...

about the cost, have you valuated a reptil cfl? some have a 10% uv-b output, on the total nominal output.
if i've read it well the uv-b works on different photoreceptor, are you keeping a journal on that grow, Avid?


edit: removed some crap i wrote, after i did read the link provided.
 
Last edited:
Dion

Dion

Active member
jikko77 said:
i do know osram have a multiband far red starting from 700 to 730 nm, or at least i do remeber something like that.
if you think on watt the far red ammount should be on 34 or so watt.
do you have a quote for the far red ratio?
and this is totaly imho: a mix of 3000°k and 5000°k (90cri and 80cri) would cover the par spectrum better than just a single 3000, 4000 and even 5000°k, leaving out just the 700nm pick.

this is a 3070 5000°k:

[URL=https://www.icmag.com/ic/picture.php?albumid=65534&pictureid=1609496&thumb=1]View Image[/url]

source: cutter.au



about the cost, have you valuated a reptil cfl? some have a 10% uv-b output, on the total nominal output.
if i've read it well the uv-b works on different photoreceptor, are you keeping a journal on that grow, Avid?
Click to expand...

did u read the posts by beta test team?

https://www.icmag.com/ic/showthread.php?threadid=293711
 
O

olekingkole

Active member
I use 4 Philips Greenpower 14 watt far red bulbs in a 12x12 room to trigger night cycles. This way I can flower with 13 hours of light/day. This shortens flowering time by roughly a week. I could probably push it to 13.5 hours/day. The only problem I've experienced is getting all timers sequenced properly. Digital timers make it easier. You have to be certain that the far red lights really come on for 10 minutes after lights out. If the plants don't go into flower quickly, you may have your timers mis-set. I also use 4 Agro-Max Pure UVB t5's for 1 1/2 hours/day in 6 15 minute intervals. These provide much more UVB than the reptile bulbs.
 
L

Lysrgic

New member
olekingkole said:
I use 4 Philips Greenpower 14 watt far red bulbs in a 12x12 room to trigger night cycles. This way I can flower with 13 hours of light/day. This shortens flowering time by roughly a week. I could probably push it to 13.5 hours/day. The only problem I've experienced is getting all timers sequenced properly. Digital timers make it easier. You have to be certain that the far red lights really come on for 10 minutes after lights out. If the plants don't go into flower quickly, you may have your timers mis-set. I also use 4 Agro-Max Pure UVB t5's for 1 1/2 hours/day in 6 15 minute intervals. These provide much more UVB than the reptile bulbs.
Click to expand...

Sound pretty awesome man! When exactly are you turning USB? Middle of day?

I got myself 5 of the LZ1-10R300 740 nm. Do you think ghost will be enough or to maybe even to much for a 1.2X1.2 m??

I should turn them on for the entire 12 hours of light, and that another 10 before and after, right? Having a thought about using dimming (middle of the day is Max peak?)
 
O

olekingkole

Active member
I don't know if 740 nm led's will work. Mine are 730 nm and that's the wavelength at which the plant responds. I set them to come on five minutes before lights out and run them for 10 minutes after lights out. That's all that's necessary to put the plants to sleep. I run the UVB tubes for 6 fifteen minute intervals during the middle of the daily light period. That seems to be enough. Too much UVB can damage the leaves and reduce yield. Some people run the reptile bulbs a full 12 hours a day. These bulbs are much weaker than the Agro-Max bulbs, so running them longer makes sense.
 
Dion

Dion

Active member
olekingkole said:
What is your point, Dion? How is the McCree Curve relevant to the phytochrome reaction?
Click to expand...

that was not in responce to ur post mate more for general reference in regards to driving photosynthesis under leds

but seen as u ask

Phytochrome_absorbtion.png



https://en.wikipedia.org/wiki/Phytochrome

this shows that 650-720 seems to be the nm resposible for the reaction dropping off right around where mmccrees curve does


so ur 730s would be better than 740 i reckon

where did u get 730/740nm from?

an interesting question(at least to me as someone would builds leds and can recreate almost any immaginale spectrum) is

how much IR and or UV should we be using (like a % of total light for each?)
 
jikko77

jikko77

Active member
check beta test team album.
there is a light absorption graph, its from the very begin to the very end of a full grow cycle.
it show how much % and what wave lenght are needed.

as i have understood the deal:
the max pick is on 735 nm, most led have a delta of +- 10nm (or at least i've read so), carefull when you pick a far red led.
in some of their post they have talked about how many watt are needed, can't remener the specific quote, but they were a low watt quantity. i guess is a kind of fixed % over the total light emitted.

on what led do you need: it depends on what led you use to cover the par section of the grow light. that's why i'd like to get a read with a spectrometer.

i.e.: according to cree d.s. a cxb 3070 90cri 3000°k has a 60% value on the 680 nm, according to this i'd pick a mono covering from 680 to 730 nm to get the red/far red covered. same deal on the other side, with blue and uv. even green and orange.

as far as i've noticed, and as far as cutter say, some cxb has a very little far red and uv output.

here some led sample from cutter:
xpe: http://www.cutter.com.au/proddetail.php?prod=cut2841
4x xpe: http://www.cutter.com.au/proddetail.php?prod=cut2202
2x xpe 660 and 730 nm: http://www.cutter.com.au/proddetail.php?prod=cut2857
 
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