User Survey: Min Distance "you" Run Cob From Foliage. Include Type, Watt's Per Cob.

[Horto]

User Survey: Min Distance "you" run COB from foliage.
Include:
1/ Minimum distance from foliage.
2/ Type and Watt's per COB.

There is no right or wrong answers, just different practices and choice.
I am hoping to get as many participants as possible.

Keep it simple :)
Horto

 

[jumpincactus]

Gonna bump this as I am gearing towards losing my HPS lighting for alternate sources. LED being one of my consideratons. So I would like to know the answer to this as well.

In addition, if the OP doesnt mind, I would like to know first hand from LED users are they as cool running as the mfgrs would have us believe ? Will I have less of a hassle keeping my enviro cooled in comparison to HID.?

I actually read somehwere that that claim is misleading. Any input from led folks.?

 

[Homesteader]

@jumpincactus
COBs vs 1w diodes vs 3w-5w diodes.

They all produce some heat but not nearly as much as HPS even with 5w diodes. My unit uses 5w diodes and it produces enough heat to run CO2 effectivly but it is still just warm to the touch. COBs can be driven softly if you are looking to minimize heat you would just need to add more of them.

I don't use COBs but I run my 5w diodes at 15" probably and never have any burns so I would imagine a COB could be dropped even less.

 

[Horto]

@jumpincactus
COBs vs 1w diodes vs 3w-5w diodes.

They all produce some heat but not nearly as much as HPS even with 5w diodes. My unit uses 5w diodes and it produces enough heat to run CO2 effectivly but it is still just warm to the touch. COBs can be driven softly if you are looking to minimize heat you would just need to add more of them.

I don't use COBs but I run my 5w diodes at 15" probably and never have any burns so I would imagine a COB could be dropped even less.

I would really like to isolate the distance required to prevent bleaching, assuming good ventilation!
Suspect that valid arguments will come hard and fast, to include heat damage, but it is more variable then Bleaching distance for lower temperatures.

My personal interest is the distance bleaching occurs in a well vented cool environment, but will take what I can get.

Thanks

 

[Horto]

I would like to know first hand from LED users are they as cool running as the mfgrs would have us believe ?

I don't mind at all.

Good LED design might not produce as much heat per watt, but the application of this light is not seeing the full potential. There seems to be a few glued on ideas, perhaps because more industry is getting involved.

Lets see.

 

[Homesteader]

I think it comes down to leaf temps and most people don't have the meter to read IR temps on leaves. I think a lot depends on the ambient temp.

 

[Horto]

I think it comes down to leaf temps and most people don't have the meter to read IR temps on leaves. I think a lot depends on the ambient temp.

That's what I thought. Now my thinking is that Heat burn of Leaves through radiant heat from bulb is felt as uncomfortable to the back of your hand.
Bleaching occurs at a specific distance that is comfortable to the back of your hand with good ventilation.

I am not saying people are not ventilating across the top of foliage.
Just that Bleaching might have a minimum more fixed to the spectrum and frequencies of artificial lights.

Should add that leaf temperature might be a good way to answer the question.
As long as other conditions are reasonably controlled.
Bleaching could be made worse by low pH, not sure if I can make this connection with confidence, but it did seem to make mild bleaching worse!

 

[Horto]

Could be wrong on this. Anybody shed any light on the bleaching process. Ha :fire:

 

[bobby g]

I don't mind at all.

Good LED design might not produce as much heat per watt

it actually produces exactly as much heat per watt

 

[Horto]

it actually produces exactly as much heat per watt

I should have been more specific in the equivalent Wattage for the same working light, but there in lies the whole problem.

Not convinced of the merit in LED's against HPS at this time!
Without some real data over variables, its a big change for questionable gain.
The idea your choice should be based on Eco credentials is not a strong argument unless you were growing lettuce.

Guess a Lot of people have purchased Commercial LED Systems, a few make Kits that are very similar to the commercial systems. If Manufactures give a recommendation for their product it become the answer.

 

[bobby g]

Not convinced of the merit in LED's against HPS at this time!
Without some real data over variables, its a big change for questionable gain.

im not seeign a lot of hps journals with >1.4 g/watt, which is pretty common in the cob world. if DE hps guys get 3 p off a light they are shitting themselves at that 1.2 g/W

 

[sixstring]

Not convinced of the merit in LED's against HPS at this time!
Without some real data over variables, its a big change for questionable gain.
The idea your choice should be based on Eco credentials is not a strong argument unless you were growing lettuce.
.

the gains are not questionable with led,even the shittiest leds(mars hydro) will grow dank plants.you choice should be based on your goals,not what someone else needs or uses,but if you want to save on power bills and keep or exceed yields from typical hid lights then cob leds are a great place to start.i put these 30 x 35 w cree cobs in where i used to have 3 x 600hps hung so i have dropped from 1800w to about 1200w and im seeing increased yields,less heat,and much healthier plants.so for me its a no brainer.since installing the first section i have continued to build light bars to replace another 3 x 600w hps and mh lamps.im down about 1400w now in usage and i def have alot better coverage in these areas.and ppfd is fanfuckintastic :cool:

 

[Horto]

im not seeign a lot of hps journals with >1.4 g/watt, which is pretty common in the cob world. if DE hps guys get 3 p off a light they are shitting themselves at that 1.2 g/W

I understand the use of close planted clones under lights, and use a similar practice outside in rows 10 inches apart late in season.

Guess you are referring to

400 watt Philips "Master Son-T Pia Plus" under 88 cm wide Parabola, length 60 cm.

This system gives me 16 ounce from 4 plants, 1.1 gram per watt.

The first Parabola was made within the limitations of recycled materials.
The Mylar finish was before I knew of Cement or Film Adhesives, Elmers wood glue took a long time to cure.
Now doing some final changes, the sides will also be extended to 100cm and length increased from 60 to 90cm for full utilization of light.

Based on the experience of first design, this should give me another %10 more growing area of usable light.
I have not considered what the Max gram per watt might be?
It is not really the point without deciding on the feeding method.
I grow 4 plants using a modified NFT system with a maximum of 6 Plants, the trunk get a bit over 1 inch at maturity which also indicates crop. That said; I don't know that 1.7 grams per watt of 6 plants is realistic?
Let you know :)

There is a lot of different systems and claims all over the internet.
Happy to share what I know, If you are getting 1.4 gram per watt with a system that can be built from parts?
I would like to know the combination of specific driver and specific COB's names that it was achieved with.
If you or anybody else wishes to put forward the specific part codes I am all ears, and utters.
https://www.thcfarmer.com/community/threads/led-to-replace-400w-hps-in-parabola.84623/

 

[yooper420]

Just built a 200 watt cob LED light. Happy as hell with the results. Now I need to get the cash together to build 3 more to cover my space. My old LED`s (Advanced DS 300`s), were kept 16-18 inches above. Thinking the new cob LED will be similar distance.

 

[Horto]

Just built a 200 watt cob LED light. Happy as hell with the results. Now I need to get the cash together to build 3 more to cover my space. My old LED`s (Advanced DS 300`s), were kept 16-18 inches above. Thinking the new cob LED will be similar distance.

I am interested in what drivers people are using and the number and types of COB's used.
There are a limited number of efficient combinations possible, if we can create a detailed list it could help people choose for there own use, and reduce a lot of replicated questions.

Keep my posted on what you choose.

Horto