DIY LED selection for FLOWERING

[turnip brain]

Maybe these articles will help you.

http://www.lzi.lt/tomai/97(2)tomas/97_2_tomas_str11.pdf

Thanks, the way I read this, it doesn't provide any new info really, just somewhat supports some of what SDS has already been demonstrating through many many such articles. The only real pertinent info I see is the stretch from red. SDS argues that in early flower, lower red and higher blue levels help keep internodes more compact.

 

[turnip brain]

the nasa tests found that very little blue was needed to grow like lettuce or something

Honestly, with what has already been looked at /discussed, I don;t find researh about lettuce and strawberries terribly pertinent. I think we are already beyond growing in general and the overall discussions have become more specific to MJ

of course we also know that a little more blue light tends to keep canna a little more compact

That's what I am talking about!

YMMV on how that affects your decisions and what is optimum for 1 strain may not be optimum for another as well as what is optimum for 1 grower may not be optimum for another

Yep

the only way to definitively answer your questions would be for someone to do side by sides w/ that various configs of interest @ the scale you intend to grow

Yep

i did wonder about and read in to the discussion about too much 660 and possible adverse effects/benefits of more near red ~its basically another refer to the above scenario {strain/grower/scale dependent and the evidence/data we are working from is anecdotal/subjective}

Maybe

so a kind of thing where; yeah ~ WW will work by itself/a little more blue wouldnt hurt {particularly if you may prefer more compact growth} and some more red probably wouldnt hurt either {but then you get away from 'simple'}

If adding CW to WW results in enough blue this doesn't muck up simplicity in terms of running WW/CW blends of similar outputs, i.e. no need for separate drivers current etc. Adding separate reds potentially does, yes.

there are those having success w/ some various differing combos of WW/NW/CW & the consensus is that XML defo delivers as far as lumens/watt and intensity

Some argument remains about relative efficiencies, blending/spread

and; its a wormhole where you can just keep considering varying possibilities, combos and, anecdotal data sets ~probably best to look for data sets close to the scale of grow you want to pull off

That is what I have been doing, and this provides a bewildering array of variations. essentially the reason I started this thread.

this thread has a lot of consideration relative to white cree diodes

Yeah, read that one several times, don't take it as gospel, and found it inconclusive in outcome relating to spectrum. I found the build discussion helpful, and it introduced the CW/NW/CW concept to me, but pretty uncontrolled unquantifiable grow outcomes.

I'm still searching for answers but might be coming close to just winging it based on averages of spectral discussion

A little related spectrum research...

http://www.youtube.com/watch?v=XhFgQTSOkeY

 

[turnip brain]

A51 is very tuned into developing its' panels for mmj. Been following their posts in DIY on another site- very helpful, informative, with vg 411

Also looks like grow outcomes with their lights are quite good

Hans as a vg panel for closet grows, but has been very stubborn about using white in place of R/Bs

xmobotx

I am in agreement regarding CW (~6000K). Alas, CW not common in household globes stuck with NW (~5000K). That said, their actual colors are all over the place. I have several 5000K that look more like 6000K

IMO, 660s are oversold, but probably need more when the whites are CW. >90% of PS takes place in the ~630+ nm range. NW have ample ~ 630, and therefor do not require much 660, say ~ 10%, whereas CW needs ~ 10% 660, but also need 640 & 650 (~30/20%)

Appreciate that opinion, I'll add to the decision making matrix

Petflora, I have read many of your posts in these threads, and I appreciate your thinking, but I do find it hard to really find solid ground due to exactly what you are saying here about the lack of consistency and directly comparable data from your LED bulb supplementation compared to purpose built fixtures with well nailed down specs. Have I missed any LED fixture projects you have built from emitters?

Cheers

 

[turnip brain]

OK, so here are conceptual design schemes I am seriously considering at this point. I haven't had time to start plug in all emitter combinations into spectrum modeling graphs yet, but will start playing around with that soon:

Certainly convinced that modules of some sort will be the way to go, probably secured into one effective "panel" with a frame rather than a single massive panel. Not sure yet whether several parallel bars or 4 rectangular chunks. Advantage is better airflow "through" the panel for both heatsink cooling and canopy air circulation

variation 1- xm-l predominately WW with a few CW thrown in for more solid blue range. run around 1750ma

Advantages: KISS. simplicity in LED/driver selection. less to mount solder

Possible disadvantages: Less efficient than xt-e run at 700ma, could be a little lacking in deep/far red, not as good even spread mixing these higher output emitters. Regarding penetration, My grow space dictates a controlled level canopy, Scrog/mainline etc, so theoretically, even spread is more important than deep penetration.


variation 2-as above but change one string/driver to 700ma and add a string of deep red/ far red and possibly change some WW to NW or even CW for blue and added overall output since they are more efficient than WW. This next bit is not KISS, but this also allows the possibility to switch or dim the extra red in order to start flowering with proportionally more blues to keep internodes shorter, and crank up reds into flowering cycle.

Possible advantage: more controlled red/blue balance amidst the whites, and adjusting for plant need transitioning into flower and through flower cycle

Disadvantage: those specific red/blue proportions for FLOWERING still remain elusive to me! More complexity, but one switched or dimmable driver circuit is not a huge amount of extra work/complexity


variation 3: xt-e rather than xm-l driven at 700ma white spectrum as version 1 above

Same advantages/disadvantages as version 1 + better spread and blending, probably can also keep closer to canopy that higher power xm-ls

Extra disadvantage of double the components to mount/solder,


variation 4: Xt-e and possibly other brand/model roughly same variation considerations with spectrum as #2 above also possibly switched or dimmable deep red/far red driver circuit

advantages: better efficiency, easier to mess with different proportions of discrete emitters, better spread and blending, probably can also keep closer to canopy that higher power xm-ls

Disadvantages: twice the work mounting/soldering,



SO, now I'll start playing with spectrum graph modelling and look at relative build and ongoing energy costs.

 

[xmobotx]

playing w/ the graph will probably be a good idea

 

[jcmjrt]

Regarding penetration, My grow space dictates a controlled level canopy, Scrog/mainline etc, so theoretically, even spread is more important than deep penetration.

TB, since penetration isn't terribly important due to your style of grow, I'd think that the XMLs wouldn't be all that advantageous. The XTEs should give you what you need at a slightly cheaper cost. As far as spectrum - modeling it is a good idea.

I've been diying some fixtures and the last ones that I made used aluminum square tubes for heatsinks with a pressurizing fan (see stevesleds.com - the manifold idea works great and I'm keeping 60 inches of tubing cool to the touch...not warm at all) and I mounted XMLs driven at 2100mA on them. I did this because I'm not scrogging and tend to grow a few large plants...and this lighting was meant to fill in on the length of my grow space. In the center of my room, I have a spectral spinner with Kessil H350 magentas and a couple of small diy fixtures which I mount on the spinner to give me better spectrum for the time of the grow. I'm veging right now and running a neutral white and royal blue fixture. Later, I'll change out these small fixtures to white and deep red and then deep red and deep red. I used 10 WW XMLs and 4 CW ones. I might be a little heavy on the blue if anything. If I didn't have the spectral spinner with nearby deep red (which I will when flower time comes along), I'd probably have added some deep red. I think that the WWs provide plenty of 630 nm red but look at the graphs and make up your own mind. I'm certainly not the expert...just someone who is interested and has done a little LED growing and diying.

Anyway, I'm also thinking about straight side lighting on one long side of the tent for late flower and so thinking about using the 3 watt XTEs and Luxeon ESs (660nm) since I'll be getting the fixture close to the plants...and even then I'll probably run them at low amperage...still thinking about this one...

Once you get the soldering iron out and ready to go, a few more LEDs to solder really isn't a big deal. As far as mounting, I use the Berquist thermal pads and have been happy with them. Just make sure that the surface you are applying them to is clean and dry and you'll get good grip and excellent heat transfer.

 

[PetFlora]

Petflora, I have read many of your posts in these threads, and I appreciate your thinking, but I do find it hard to really find solid ground due to exactly what you are saying here about the lack of consistency and directly comparable data from your LED bulb supplementation compared to purpose built fixtures with well nailed down specs. Have I missed any LED fixture projects you have built from emitters?

Cheers

Nothing purposeful built, but the broad brush 411 is sound enough, much based on several years as an avid mmj led student and DIY follower on other forums

 

[turnip brain]

Fair enough PetFlora, I do appreciate your input!

 

[turnip brain]

TB, since penetration isn't terribly important due to your style of grow, I'd think that the XMLs wouldn't be all that advantageous. The XTEs should give you what you need at a slightly cheaper cost. As far as spectrum - modeling it is a good idea.

I've been diying some fixtures and the last ones that I made used aluminum square tubes for heatsinks with a pressurizing fan (see stevesleds.com - the manifold idea works great and I'm keeping 60 inches of tubing cool to the touch...not warm at all) and I mounted XMLs driven at 2100mA on them. I did this because I'm not scrogging and tend to grow a few large plants...and this lighting was meant to fill in on the length of my grow space. In the center of my room, I have a spectral spinner with Kessil H350 magentas and a couple of small diy fixtures which I mount on the spinner to give me better spectrum for the time of the grow. I'm veging right now and running a neutral white and royal blue fixture. Later, I'll change out these small fixtures to white and deep red and then deep red and deep red. I used 10 WW XMLs and 4 CW ones. I might be a little heavy on the blue if anything. If I didn't have the spectral spinner with nearby deep red (which I will when flower time comes along), I'd probably have added some deep red. I think that the WWs provide plenty of 630 nm red but look at the graphs and make up your own mind. I'm certainly not the expert...just someone who is interested and has done a little LED growing and diying.

Anyway, I'm also thinking about straight side lighting on one long side of the tent for late flower and so thinking about using the 3 watt XTEs and Luxeon ESs (660nm) since I'll be getting the fixture close to the plants...and even then I'll probably run them at low amperage...still thinking about this one...

Once you get the soldering iron out and ready to go, a few more LEDs to solder really isn't a big deal. As far as mounting, I use the Berquist thermal pads and have been happy with them. Just make sure that the surface you are applying them to is clean and dry and you'll get good grip and excellent heat transfer.

Thanks for your post. The active tube heat sink seems like potentially a great idea. So if I read you right, you have 14 xml @ 2100ma on 60" of 1 1/4 sq aluminum tubing? Have you tested actual emitter operating temp?

Can you tell me how you loaded the tubes, i.e. spacing?


Reading steves website, I have to wonder about statements like:

"Why do people choose Cree then? Misinformation, by poorly education people on internet forums."

bad grammar along with attitude!

What say all of you cree afficianados?

 

[jcmjrt]

Thanks for your post. The active tube heat sink seems like potentially a great idea. So if I read you right, you have 14 xml @ 2100ma on 60" of 1 1/4 sq aluminum tubing? Have you tested actual emitter operating temp?

Yep 14 of 'em at 2100 mA and the 60" includes a few inches for the manifold...it's all heat sink.

No, I haven't measured it but I could grab it and hold onto it all day long...really is very cool. I could have easily mounted more XMLs on that heat sink...I do use the pressurizing fan that Steve sells....works a champ and quiet.

I think that Cree tends to have better whites and Philips Luxeon tends to have better royal blue and deep red. Some folks are talking about Oslon for deep red as well.

 

[turnip brain]

Yep 14 of 'em at 2100 mA and the 60" includes a few inches for the manifold...it's all heat sink.

No, I haven't measured it but I could grab it and hold onto it all day long...really is very cool. I could have easily mounted more XMLs on that heat sink...I do use the pressurizing fan that Steve sells....works a champ and quiet.

I think that Cree tends to have better whites and Philips Luxeon tends to have better royal blue and deep red. Some folks are talking about Oslon for deep red as well.

Steves fan recommendations ("I would use two 10" heat sinks, side by side, each with their own fan") Sheesh! two fans for 20" of tube??? Adds up to a heck of a lot of fans and cost! Could potentially build a set of intake and exhaust manifolds to pressurize several bars.

Is yours a single 60" long piece? and do you use his fan regulator or just let it run on 24v wide open?

Hmm, even could use the whole tube arrangement like vented hoods/cool tubes if desired. But hopefully will reduce heat enough just by changing to LED from HPS.

 

[jcmjrt]

Is yours a single 60" long piece? and do you use his fan regulator or just let it run on 24v wide open?

Hmm, even could use the whole tube arrangement like vented hoods/cool tubes if desired. But hopefully will reduce heat enough just by changing to LED from HPS.

No, I built a manifold for two tubes....you can see that kind of thing in some of his kits. I did use his fan regulator.

The heat reduction from HPS to LED is incredible. I had to add a heater to my tent this winter. Next time I'll just add some compact fluorescent lights to get some more light with the heat...and hopefully that will be enough. I'm running a little less than 3 degrees over ambient so I'm just approaching 82F as the max for the day now.

 

[Chloemobile]

I have just recently started getting into LED's thanks to trem0lo's thread xmobotx, Gp73, MR.X, Verdant Green,Repuk - I have done about 8 hours of straight LED reading over the past day or two and still am unsure about how to proceed.

This thread answered many questions I have about selection because it really depends on how you want to grow your plants to tailor your LED selection. I am not an aficionado yet with the terminology, so please excuse me if I sound a bit uninformed.

I read Repuk's thread where he went with all CW and NW and thought that a little FAR RED would have been beneficial.

I think my HML needs more far-red, buds took longer to develop and ripen, and some plants (Atomics) didn't fully develop.

I only bring this up based on the discussion that there may be enough red (630) in one of the whites(NW I think?)

Then someone mentioned that the XLs wouldn't be necessary for low penetration techniques (Scrog).Wouldnt the light efficiency and brightness of those lights be better for any situation? or was it a cost thing?

I ask because i am also speculating on an LED build for my micro scrog cabinet. I am beginning to get the grasp on things but I dont think im up to date with the way they are built. I understand using cheap components is a good way to be disappointed with LED's. I have an area that is 11"11" with a max growing height of about 20" accounting for the must haves in a grow.

Do i need to make a fixture that is as big as the cabinet allows or can i use a 6 inch square heat sink? I see people using longer bar fixtures more now than blocky heat sinks.. Ive seen some LED's placed really close together in formations (MR.X) and others far apart..i guess these are some of the things im still confused about after reading...

How would you do it? Right now my plan is to copy the one that Trem0lo did, but his is a couple of years old which is i guess what im wondering if there is a way to replicate his but with newer better models?

 

[xmobotx]

i did something to the effect of trem0lo's pattern w/ lumiled rebel ww,660s and royal blues

~jury's still out

 

[danhalen]

xp-e red, philips rebel 660, and xp-g ww in 1:1:1 ratio yielded much better density than any "white" light used alone (fluorescent or led). trichs always there with white light, but the more of that deep red range put in flower the better the yield. the rebel 660 are a really nice light, maybe going to try them in 2:1 combo with xm-l ww. and there arent deeper wavelengths ive heard of being any good yet. they just love that deep red. methinks the blue range just needs to be there to a limited functional extent. its the red range that triggers flowering response. if im wrong and they are needing more blue, just drive the xm-l higher until one hits the sweet spot. truthfully the ideal wavelength (for flowering) is higher than the philips, but the effect as i understand it is to augment the white light, which are very powerful and certainly provide enough food, so its red range is boosted. 660 is the best bang for the buck in the deepening department, using lower wavelengths is like making an octane mixture with the mid grade. It just adds volume without having much effect. anyone know of deeper reds???????????