DIY COB reflectors

[SupraSPL]

In your situation lenses and reflectors are pretty close to a waste. 4 1.4a cxa's is plenty in that space.
I would actually say no to lenses. If ornate really set on additions to your light...go reflectors.

Is there a reason you think bare is bad? 99% of all cob grows online have been no reflectors or lenses.

In the end it's all the same PPF. And actually bare might have the most PPF delived if hung/used right. intensity is nice...but bare cobs aren't lacking in it. Lenses are great for small single die chips that are near worthless without more of their buddies packed around, and without lenses to help their relative weakness.

I guess I am guilty, suspecting that bare is 'squandering a lot of its potential', especially at distances to canopy over 8". Although plenty of bare COBs have had awesome results, I believe we should be seeing consistently phenomenal results and that lenses/reflectors is what will get us there, along with continually increasing efficiency.

The main reason I believe that is because of my amazement at how much the intensity increases when I add a reflector and especially a lens. And then realization of how much light is emitted outside the 120 degree cone. I am a big believer in sufficient intensity PPFD in as much of the canopy as possible, by whatever means.

Anyway that is all subject to change, but it is a hunch I have a lot of hope in. If it turns out to be even a 10% increase I will be loving it. If it turns out to be nothing, thats all good at least we know we are using them to their full potential.

 

[Lighterfighter]

Ya I think supra is getting at this i sjust one point in testing, we are being scientists in a slow lab, so testing is always an on going thing. Any gain in efficinecy is worht note as it could help grow more. I was looking at lenses due to canopy penetration. I would say grow method is important as it dictates height, ehich i really the limit for LED. We can run efficient, We can run cool, but we cant seem to pemnetrate past 18 in. Green has a great point tho too, He is stating the cob will do well and is really likely to outperform any led you buy, so the lens issue doesnt have to be adressed right away, it can be added once built(esp considering we are at a test and measure impass, the lenses dont have real data. And mounting them seems can be a lil bit of a pain. I dont suspect to hard to figure out.. Lenses and reflector testing are in their infancy compared to driver and led brands. gotta start at the base and work your way though the compnants. we are close to fully tested lights thanks to the many sacrifices from others. Thanks for testing leses. yall are the shit!

 

[AquariusPanta]

I guess I am guilty, suspecting that bare is 'squandering a lot of its potential', especially at distances to canopy over 8". Although plenty of bare COBs have had awesome results, I believe we should be seeing consistently phenomenal results and that lenses/reflectors is what will get us there, along with continually increasing efficiency.

The main reason I believe that is because of my amazement at how much the intensity increases when I add a reflector and especially a lens. And then realization of how much light is emitted outside the 120 degree cone. I am a big believer in sufficient intensity PPFD in as much of the canopy as possible, by whatever means.

Anyway that is all subject to change, but it is a hunch I have a lot of hope in. If it turns out to be even a 10% increase I will be loving it. If it turns out to be nothing, thats all good at least we know we are using them to their full potential.

I know you're right about it.

Using reflectors or lenses HAS to be more efficient than depending on white walls or mylar tents to utilize the stray photons that emit at those wide angles. I had thought we, as a community of DIYers, had come to the conclusion that equipping the COBs allowed us to maximize the potential of our beloved lights...

The only thing that I see as a lingering problem with reflectors or lenses is that distance, height in our case, dictates how our plants develop.

Take the sun and the planetary bodies as an example. Mercury is the equivalent of using one of those new 960W COBs, equipped with lenses, at a distance of a few inches away from a plant. It gets cooked. I'm probably underscoring the comparison of the two cases but hopefully you all get the picture.

Then you have Earth. Obviously there is a LOT more that goes into the equation when dealing with how our planet is structured in comparison to others but the basis of my point is that life on Gaia was able to prosper because of the right intensity of light given off from the Sun.

I may be swaying with my analogies but it all comes back to lenses and reflectors, which have been around for awhile now but are relatively new in the COB-horticulture arena. There are going to be cases where reflectors and lenses, despite the benefits they offer, cannot be applied in certain circumstances, which can be likened to that of high-intensity lights, such as HID, HPS, and our favorite, COBs (Vero 29, CXB3590). Take for example a 2'x2'x4' grow space - you're going to have to rethink your setup, all the way from amperage to amount of COBs, if you intend to use reflectors and/or lenses.

I believe our collective research, as a forum community, will over time provide insight on various scenarios that we, as horticulturists, can commonly come come across and relate to and I think you and a few others are leading the herd in that sense.

 

[Greengenes707]

If a reflector is 90% and so is a reflective wall...is there a difference?
That is my point with small areas.

In the end it doesn't matter what you use as long as you meet the plants requirements. These light requirements are not new or specific to any lighting. Light is light.
I have been using led well before cobs and know quite well what lenses can do. And how they can step up intensity...but it's still all the same PPF assuming similar efficiencies. Reflectors are probably the most under studied in our industry. And personally think that is the best option for harnessing the PPF into PPFD while still meeting the whole canopies requirements and minimizing photon losses.

If cobs lacked intensity I would be all over lenses...but they don't. I don't need more intensity...just a little cleaning up/wrangling around the edges.

 

[AquariusPanta]

If a reflector is 90% and so is a reflective wall...is there a difference?
That is my point with small areas.

In the end it doesn't matter what you use as long as you meet the plants requirements. These light requirements are not new or specific to any lighting. Light is light.
I have been using led well before cobs and know quite well what lenses can do. And how they can step up intensity...but it's still all the same PPF assuming similar efficiencies. Reflectors are probably the most under studied in our industry. And personally think that is the best option for harnessing the PPF into PPFD while still meeting the whole canopies requirements and minimizing photon losses.

If cobs lacked intensity I would be all over lenses...but they don't. I don't need more intensity...just a little cleaning up/wrangling around the edges.

I would argue your first sentence as whole, with reflectors and walls being similar in reflective properties/abilities, but you were specific with mentioning small areas. Still could be argued, in that a reflector is boxing the light on a fixed position of the canopy, while the tent encompasses the whole plant and container, hence allowing light to bounce all over (not as effective as manipulating the path of light as the reflector). Both of these modifications to how we grow stack together, giving us more herbalism skill points (WoW term).

I do not discredit your experience and knowledge of PPF and other similar terminology, as I lack in equivalency, but I do get the impression that you are underscoring the subject in some sense or another and for reasons I do not fully understand.

I like the idea of using reflectors in future applications.

I agree with you that legitimate COBs today, when compared to mono LEDs, don't necessarily NEED reflectors or lenses in order to deliver the plant's demands of light intensity. BUT there are always exceptions, something any wise soul would concur, which fuels the motivation of not only mine but other's knowledge of using reflectors and lenses; we want to know the boundary of our boundaries within our growing operations.

 

[Lighterfighter]

Imo, There is a reason that light companies offer a series of products instead of one for all needs lol. each situation has many solutions but generally a few are best fit. Ill use the two posited situations to find when lenses and reflectors are most relevant. Keep in mind most led start with a lens angle <120 so adding 30 degrees of focus or more with reflectors. I believe the one main variable is depth. 18-24 in of canopy is pushing it for just a cob. no lenses ore reflectors is best suited for sog scrog lolipoping topping and fiming. 4ft is not that tall the plants start at a foot tall, 3 ft to top- 6iin of light meaning 30in max of growth space. Penetration wont be an issue if its nice and reflective on the inside. Users with bigger areas and larger canopy size will find that this addition would be most beneficial. Take into consideration the plant type, eg sativa. you BEtTER be looking for somthing that can push down deep. Without penetration, Youll miss so much due to the fact that the length of the plant is jsut past whats best for led no matter how small you start em lol. you would prefer a light that diminishes less over the distance. Conclusion is, on satvas or large open area lenses and reflectors would provide a substantial increase in efficiency. small areas with reflective materal lineing the sides (smaller then 6sqft) would benefit less.

Or as aquas saying theres still some benefit to reflectors as they lesses the distance needed to travel to hit canopy, or due to angular reflections taking more distance to hit their target. straightest distance to canopy is down, not left to wall then at random angle down. Lower parts still benefit some, but who cares about popcorn, Untill standardized reflectors come out for its hard to test and measure. or expensive lol.

 

[AquariusPanta]

Success Formula:

(Reflector or Lenses) + (COB from Bridgelux or Cree) + (Low-current and efficient driver from MW) = Win

 

[Lighterfighter]

@AquariusPanta any recommendation on lenseS? I am almost following that model. cxa3950 (well cxb, but same size) 1050 instead of 700 mA mw driver. I want the extra lumens.

 

[AquariusPanta]

aqua any recommendation on lenseS? I am almost following that model. 1050 instead of 700 mA. I want the extra lumens.

I got nothing for you other then taking up Supra's practice of cutting apart plastic soda bottles and painting em' white. I think he uses Kapton tape to secure the DIY reflectors to his COBs.

 

[churchhaze]

Tape and plastic bottles, but trust me, it's all bleeding edge tech! lol

 

[Lighterfighter]

well, no worries, I can jimmy rig somthing up. I am def ganan buy some lenses. Ill wait till I get the cob up and iIl measure the dimensions and start making calls to king brite and some others to find one thatll fit

 

[Lighterfighter]

I am starting to get the feeling that I am ganan have to produce something to document my build and results. I am getting the gear the 16, I just flipped my veggies to 12/12 under my mars 2 yesterday. This means that right as the stretch finished, Ill be able to pop up the new light and compare the two. at least in the facet I found the mars to lack, in weight! seriously though guys, thanks for everything.

 

[Lighterfighter]

I got bored so this is an example of how reflectors help. Now its terable, but funny lol. As you see the red lines are without reflector. The distance is so much farther. meaning depreciation in lumens.

 

[Greengenes707]

I would argue your first sentence as whole, with reflectors and walls being similar in reflective properties/abilities, but you were specific with mentioning small areas. Still could be argued, in that a reflector is boxing the light on a fixed position of the canopy, while the tent encompasses the whole plant and container, hence allowing light to bounce all over (not as effective as manipulating the path of light as the reflector). Both of these modifications to how we grow stack together, giving us more herbalism skill points (WoW term).

I do not discredit your experience and knowledge of PPF and other similar terminology, as I lack in equivalency, but I do get the impression that you are underscoring the subject in some sense or another and for reasons I do not fully understand.

I like the idea of using reflectors in future applications.

I agree with you that legitimate COBs today, when compared to mono LEDs, don't necessarily NEED reflectors or lenses in order to deliver the plant's demands of light intensity. BUT there are always exceptions, something any wise soul would concur, which fuels the motivation of not only mine but other's knowledge of using reflectors and lenses; we want to know the boundary of our boundaries within our growing operations.

Go and read my post before the one you just responded to and you see I say in small areas that lenses and reflectors are not needed to get the best/most light to the plants. But in bigger open areas is where the benefits will be seen clearly.
Nowhere did I say neither were needed for certain sitiations. But with the small situation we are taking about for him, it doesn't get into lens territory imo.

And in small spaces(like tents and closets) the plants are touching the walls 99% of the time so getting light past the top canopy is very hard. Then figure if you running bare...your running closer to the canopy...minimizing bounces off the walls and surfaces before hitting the plants.
So again, best for the situation....many times could be bare.

I came from single dies with lenses...so when I got to cobs all I could say was why the fuck don't these guys put lenses these things? But then used them and am blown away by the penetration and the whole canopy intensity. It's what it should be with just a little help needed on the edges.
I also like and strive for a diffuse situation or as close to if I can without sacrificing output(hard/impossible to do). But reflectors and bare are the closet thing to it.
Multi spread sources do it too.
With the efficiency gains we keep seeing...hps is going to not be the competition anymore pretty soon. But we can always still learn from them...I'm yet to see a columnated lens hps.

A million different ways to skin a cat. Find what works for your situation. Just simplic designs/solutions are often over looked for being just that.

 

[churchhaze]

The low profile nature of my builds is why I do not use reflectors or lenses, and I think a lot of the reflector/lens users understand that.

The disadvantage to lower profile builds is obviously that you need more cobs, spread out more and to constantly be raising lights. The obvious advantage is lower ceilings with taller plants before being burned.

I do think that even in high profile builds that lenses are of questionable value and that the overlap of many unfocused cobs will ultimately amount to the same relative intensity everywhere regardless.

 

[Lighterfighter]

this sounds like the barebuild verticle grow vs. hood growing debate lol. ps i Just took the glass off my mars 2, it is brighter. Glass is def not a lens lol. I dont agree w the whole diffuser situation. I think it inversely, Diffused tarp over greenhouses prevent rays or gasses from escaping, not to magnify the glassrays. Not saying ur wrong, but supra had ran data on reflectors and a lens. Done quantifiable experiments. given its been on a small scale and there is much work to do. Ive read studies outside of here that state secondary lenses are beneficial. Straight up. they produce higher umols at farther distances... if your pumping alot of diodes into a small space, then again reflectors arent as necessary. but were talking higher wattage largely spaced diodes.

 

[AquariusPanta]

Go and read my post before the one you just responded to and you see I say in small areas that lenses and reflectors are not needed to get the best/most light to the plants. But in bigger open areas is where the benefits will be seen clearly.
Nowhere did I say neither were needed for certain sitiations. But with the small situation we are taking about for him, it doesn't get into lens territory imo.

And in small spaces(like tents and closets) the plants are touching the walls 99% of the time so getting light past the top canopy is very hard. Then figure if you running bare...your running closer to the canopy...minimizing bounces off the walls and surfaces before hitting the plants.
So again, best for the situation....many times could be bare.

I came from single dies with lenses...so when I got to cobs all I could say was why the fuck don't these guys put lenses these things? But then used them and am blown away by the penetration and the whole canopy intensity. It's what it should be with just a little help needed on the edges.
I also like and strive for a diffuse situation or as close to if I can without sacrificing output(hard/impossible to do). But reflectors and bare are the closet thing to it.
Multi spread sources do it too.
With the efficiency gains we keep seeing...hps is going to not be the competition anymore pretty soon. But we can always still learn from them...I'm yet to see a columnated lens hps.

A million different ways to skin a cat. Find what works for your situation. Just simplic designs/solutions are often over looked for being just that.

That's right, a finite amount of ways to skin a coyote (cat owners may be offended by your expression lol), which is why I'm anxious to see some results from whomever that is serious about testing and reporting their results!

I agree with a bunch of what you mentioned about light in tents and stuff. I do also think that ~90* is a sweet spot if one were to look into reflectors, although 115-120* is great for tent plants with getting the tiers below the canopy. I don't know if this is a favorable outcome of using wide-angled COBS, such as Vero, as I have little experience growing indoors.

 

[Greengenes707]

I have tested bare vs tight vs wide angle vs reflectors years ago with single dies...light is light and the results stand cob or single dies. There is a reason why Apache lenes are what they are. I have been testing reporting par numbers for a long time now. I know what and how lenses manipulate. But they don't magnify or increase photons. That is impossible. Only focus into a tighter area.
I have see very few people show what their builds are getting to the canopy in a situation. How many cob par charts have you guys seen...I can recall 2 off the top of my head and mine is one of them. Some one did a few good ones at 1050ma 1 cob per square foot but I can't remeber who.
I am the original PAR junky around here. I was a fanatic about matching footprints with 1k hps...and still am sorta. I have grown with less than 500umols and also over 1500umols. I've seen what manipulating the same PPF and spectrum up or down can do. If you can average 700-1000umols center is the sweet spot.


Nor is the defused light benefits part a guess...
https://ag.arizona.edu/ceac/sites/ag.arizona.edu.ceac/files/10 R. Hernandez Plant Lighting.pdf



I could see small vero 10 or 13 builds getting the most use out of lenses. Similar to single die. But then cost for lots of quality lenes could be prohibitive.

 

[Lighterfighter]

do you got umol comp on just straight cob vs diffused vs lens? I do understand how diffusion causes more of a glow and less of a direct beam( eg cause more sureface area at less lumens? or just straight more even distribution? I have difusers on my led gloves lol.they also take away alot from intensity from what I saw. doesnt mean my eyes are right maybe umols is diff.

 

[Greengenes707]

Where did I say diffusion over proper intensity???
Read again. I'm sick of repeating my self and coming off hostile...but truthfully am getting there. Do what ever you guys want to but please document and show it all. Not just one person who would be successful with a candle if he wanted to(supra). More of you need to start contributing to mass info if you really want things to progress. Not just get one piece from one source and regurgitate it a day later as if you have know it for years.

I'll be in my own thread occasionally...but it is time to take a big hiatus from this place.

Light is light and what plants want is what plants want. Give it to them with what makes it best...then get high.

Peace out gentleman!