Mirrors!!!

bombbudpuffa

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Would mirrors be more effective than mylar? Seems to me nothing will reflect more light than a mirror but am I wrong? Thnx!!!
 

bombbudpuffa

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I was considering building a growbox surrounded in mirrors.
 

Canso

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mirrors will cause hot spots.
dimpled alluminium would work great.
 
T

THE BROTHER'S GRUNT

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bombbudpuffa said:
Would mirrors be more effective than mylar? Seems to me nothing will reflect more light than a mirror but am I wrong? Thnx!!!
Yup i'm with everyone else on this one. I would go with either flat white paint or mylar.
 

jaz1873

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im using flat white contract paint (im a decorator nicked it from a job) lol :D
 

laylow6988

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Ok, so now I am consitering that the reason you use flat white in stead of glossy is due to the hot spots right? Wow there is so much info in here. I normally just coat the room with foil. I will use paint next time. Maybe go to mylar one day. Here is something that I read, the material, and then % reflected. Foylon 94-95%/ Reflecive Mylar 90-95%/ Flat White Paint 85-93%/ Semi-gloss White 75-80%/ Flat Yellow 70-80%/ Aluminum Foil 70-75%/ Black less than 10%. Just for some info on some types of materials.
 
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Stoney Bud

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Hey everyone, I need to jump in here and dispel a well circulated fiction about lighting on MJ crops.

What is generally referred to as "Hot Spots" that are a result of reflection from tin foil or mirrors is a fiction. Nothing like that has ever happened or will ever happen. It's a myth.

Before anyone starts jumping up and down, keep in mind that this myth has been tested in a lab environment and proven false. The infrared spectrum of light loses intensity dramatically when reflected. To have enough to actually cause a reflected "Hot Spot", you would have to have enough infrared to toast bread under, coming from the primary light source. It's just not possible to have plants under that kind of infrared without killing them instantly.

Don't feel bad if you've been sucked into the "Hot Spot" myth. I've known people who are in relatively high levels of plant biology that STILL believe it's possible. When confronted with the science behind the existence of "Hot Spots", each one eventually understands that it's just not possible with plants.

The term "Hot Spots" is a popular term used in manufacturing. In many applications, it is possible to have them and to have detrimental effects from them. When curing a paint job, it's possible. When curing certain types of sealant it's possible. When curing or drying certain types of glue, it's possible. None of these objects are harmed by the huge amount of infrared that is necessary to produce "Hot Spots".

Plants exposed to an amount of infrared capable of producing reflected "Hot Spots" will die within minutes.

The real reason for not using crumpled foil or mirrors is that neither will reflect enough usable light to do squat for a plant.

With the exception of mylar, flat white paint is your best choice for reflectivity onto plants.

Please everyone, lets not spread the myth of "Hot Spots" any more. Lets inform everyone about the reason they can't exist in a grow room.

Thanks,

Stoney.
 

laylow6988

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That's wild. I really thought reading it in a few growbooks that it would have been a fact. But, I have said it before that not all is true. Even in Jorge Cervantez's new Grower's Bible it says that "hot spots" will be created with foil. Not by light, but by UV rays. And, not to disagree... but uhm... my 500W I swear could turn bread into toast lol.
 

bombbudpuffa

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Okay...then why don't mirrors reflect light good? I'm kind of at a loss. Mirrors are very reflective and it seems they would reflect light exactly like the light thats shined on them. Stoney, why isn't this the case? Thnx!
 

laylow6988

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Grower's Bible "Specular - Mylar and mirror give the best strength of light, but it is concentrated. About 90% of the light is transferred."
 

bombbudpuffa

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I think i'll expiriment with mirrors. If it's successful, i'll let you all know. Thnx again!
 
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Stoney Bud

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laylow6988 said:
That's wild. I really thought reading it in a few grow books that it would have been a fact. But, I have said it before that not all is true. Even in Jorge Cervantez's new Grower's Bible it says that "hot spots" will be created with foil. Not by light, but by UV rays. And, not to disagree... but uhm... my 500W I swear could turn bread into toast lol.

What is also known as "Hot Spots" in a grow room are located at points in a multiple light grow room where ventilation is poor in a given spot. This causes an area of the grow room to contain a "Hot Spot". This type of hot spot is a result of poor ventilation, not reflection of light. I was referring to toasting bread at the same level as the plant tops with the light where it should be, normally. That amount of light *could* reflect enough infrared to cause harm through heat stress. However, as the plants would already be toasted, it really wouldn't matter. I hate to say it, because it sounds like blasphemy, but Jorge is wrong about this issue. A quick check with any AG university will prove it. Or, I'm very familiar with the testing procedures used to prove it. I can tell you how to test for hot spots. The equipment costs a couple of hundred bucks. Basically, it's a 4' x 4' wall covered in flat black ceramic tile that is moved two feet from a wall that is covered in wrinkled foil or whatever, and a laser temp gun is used to measure the heat on the surface of the tiles. As infrared light is always accompanied by heat, the measure of the heat on a surface that is close to the reflected light will show any radical increase in heat in any given area. It won't show any. This test has been reproduced about a thousand times or more, and the results are well known within AG scientists. You'll find absolutely NO hot spots anywhere on the tiles. The temperature will be constant for any given area of the tile surface.

bombbudpuffa said:
Okay...then why don't mirrors reflect light good? I'm kind of at a loss. Mirrors are very reflective and it seems they would reflect light exactly like the light that's shined on them. Stoney, why isn't this the case? Thnx!

Mirrors are designed to reflect light that is the same spectrum as what humans can see most clearly with. The manufacturers of mirrors make them to reflect with different levels of color and white light. These colors and white light are not what is best for plant growth and lab tests have proven that the reflected light from mirrors is far less beneficial to plants than plain, flat white paint. If you rely on mirrors for plant light, you'll be passing up about 30% of the reflected light that plants can use.

laylow6988 said:
Grower's Bible "Specular - Mylar and mirror give the best strength of light, but it is concentrated. About 90% of the light is transferred."

Mylar, yes. Mirrors, no. They're wrong. Testing by scientists have proven it already. Neither Mylar nor mirrors concentrate light, they merely reflect it. Prisms, if shaped to do so, concentrate light. Magnifying lenses concentrate light.

bombbudpuffa said:
I think I'll experiment with mirrors. If it's successful, I'll let you all know. Thnx again!

You'll grow plants. Mirrors will do that. The amount of usable light that's transferred to the plants will be about 30% less than if you had used flat, white paint.

If you would like to, and want to do a little research on the web, I'm sure you can find some papers that have been written on the subject. Pick out the search results that have college names in the hypertext link.
 

bombbudpuffa

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Thanx Stoney, you're a pretty knowledgable guy! I think i'm going to still do exp. w/ mirrors, mylar and aluminum foil. Just wanna test myself, make myself content. I appreciate the help though, seriously.
 
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Stoney Bud

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bombbudpuffa said:
Thanx Stoney, you're a pretty knowledgeable guy! I think i'm going to still do exp. w/ mirrors, mylar and aluminum foil. Just wanna test myself, make myself content. I appreciate the help though, seriously.
Ha! My pleasure man. I'm not that smart. I've just had longer to learn. Also, I'm a learning fanatic. I'm not happy unless I'm into something I don't know squat about and read, read, read, until I finally understand it. People have kidded me about it for my entire life. If you put me in a situation where I can't learn something, it puts me to sleep. Boring.

It would be a lot less expensive for you if you just looked up the data on the web. All of the testing your getting ready to do has been done already. All you need to do is read it.

Mylar is the best reflectivity, but the gain realized by using it over flat white paint is negligible. The stuff is a PITA to use, and paint is too easy.

Ha! Whatever you do, have fun and stay high.

Good luck to you man.
 

bombbudpuffa

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Ha!!! I'm the same way about learning stuff, as you can tell by the barrage of questions I throw out there. Yeah, I pretty much stuffed the exp. thing and decided to go with strictly mylar. Thnx for the help again!
 

laylow6988

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That's some good ****. Well, I was already going to paint flat white. But it's good to know that it's closer to the top than I thought. Smoke weed everyday!
 

bombbudpuffa

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mirrors will burn your room up get reflectors
No they won't! Thats what this thread has been about..."hot spots" rumors. Mirrors are reflectors.
Originally posted by Stoney Bud-What is generally referred to as "Hot Spots" that are a result of reflection from tin foil or mirrors is a fiction. Nothing like that has ever happened or will ever happen. It's a myth.
 

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