Flat white vs semi-gloss?
- Thread starter Apollo11
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kermit2692
Well-Known Member
Mylar
DemonTrich
Well-Known Member
Flat white
natureboygrower
Well-Known Member
RM3
Well-Known Member
Kilz has oil, latex and water based versions, I'd go latex
but to get serious just get a flat white made with titanium dioxide as it has the highest reflective properties
note: Kilz latex is made with titanium dioxide
natureboygrower
Well-Known Member
good tip.yeah I didn't know what kind you were talking about.i figured it probably wasn't oil based.people don't like using that anymore (oil based kilz is strong lol not as smelly as bin though)I used to use a lot of kilz (great for covering)but it definitely isn't white.you want a latex kilz that actually says "white" on the label.
I would use Behr for a grow room not for my house though.just my opinion
edit semi gloss cleans up better than flat in case there was ever a mold/mildew problem.that may not be the best finish for light reflection though
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bryan oconner
Well-Known Member
solar panels to absorb the extra lighting and pump it back into the system . lol there is a few articles about whats the best paint for a grow room suggest you google it . i would pass on both and get some thing like this http://www.htgsupply.com/categories/grow-tents-grow-room-liners/mylar dont be cheap get the thin stuff get the thick stuff buy it once and be done .
Darnova
Member
The others have mentioned which is better, so I'll give the short explanation of why.
Flat white paint is better than semi-gloss or gloss paint for exactly the same reason why using the dull side of aluminum foil is better than using the shinny side.. to prevent "hot spots". The glossy/shinny material can create hot spots of light, which results in a more focused reflection of light. The flat/dull material offers a better distribution of light to a larger area of garden & plant. Think about the narrow beam of a flashlight versus the evenly distributed light from a desk lamp.
If you can afford it, reflective mylar is the better way to go, as that comes close to a mirrored reflection of light. Of course, actual mirrors are the best, and also the most expensive.. by a lot.
Flat white paint is better than semi-gloss or gloss paint for exactly the same reason why using the dull side of aluminum foil is better than using the shinny side.. to prevent "hot spots". The glossy/shinny material can create hot spots of light, which results in a more focused reflection of light. The flat/dull material offers a better distribution of light to a larger area of garden & plant. Think about the narrow beam of a flashlight versus the evenly distributed light from a desk lamp.
If you can afford it, reflective mylar is the better way to go, as that comes close to a mirrored reflection of light. Of course, actual mirrors are the best, and also the most expensive.. by a lot.
ISK
Well-Known Member
Actually a mirror is far from the best, as mylar or even tin foil would better.... most would agree that flat white is the overall best choice
As for "hot spots" with tin foil.....1000 watt HPS maybe....23 watt CFL's very unlikely
A.K.A. Overgrowem
Well-Known Member
There are shades of white, believe hospital or sanitary white is the whitest. Go with what fits your budget. Tin foil, $2. + tape/glue. Quart of paint, $5. up + brush. KEEP your eyes open. My mylar = yard sale $1. for 2 rolls. When it comes to reflective surfaces, doing something is 1,000 times better than doing nothing. Thrift stores, yard sales = savings.
Darnova
Member
@ ISK
Uh.. what?!
You state that tin foil is a better reflective material than a mirror?
You suggest that hot spots may only happen with HID lamps?
Do you have any reputable reference in which you can direct me to see that?
https://www.rollitup.org/t/mylar-vs-aluminum-foil-vs-mirrors.18861/
Based on all of my research, the reflectance value of paint/foil/mylar/mirror has not changed a bit in the 40+ years I've been researching & growing. That's not to say I'm not open to the results of modern testing. If the info I've been operating off of has long been wrong, I'd like to know. But when someone tells me that foil presents a better reflectance value than a mirror, I'm going to need some kind of scientifically-backed verification.
I've tried to google the info, but every result states the opposite of what you say. Could you provide any links to help us out?
EDIT: Found another source..
https://books.google.com/books?id=fERzFsZhdxYC&pg=PA188&lpg=PA188&ots=t2UzcpQIUu&focus=viewport&dq="Jorge+Cervantes"+mylar+paint+foil+mirror
According to that, mylar is better than a mirror due to light lost when traveling through the glass. I suspect that depends on the type of glass and how thick it is. However, the notion that mylar may be better than a mirror is actually new to me. I'll have to check into that a bit more.
Uh.. what?!
You state that tin foil is a better reflective material than a mirror?
You suggest that hot spots may only happen with HID lamps?
Do you have any reputable reference in which you can direct me to see that?
https://www.rollitup.org/t/mylar-vs-aluminum-foil-vs-mirrors.18861/
Based on all of my research, the reflectance value of paint/foil/mylar/mirror has not changed a bit in the 40+ years I've been researching & growing. That's not to say I'm not open to the results of modern testing. If the info I've been operating off of has long been wrong, I'd like to know. But when someone tells me that foil presents a better reflectance value than a mirror, I'm going to need some kind of scientifically-backed verification.
I've tried to google the info, but every result states the opposite of what you say. Could you provide any links to help us out?
EDIT: Found another source..
https://books.google.com/books?id=fERzFsZhdxYC&pg=PA188&lpg=PA188&ots=t2UzcpQIUu&focus=viewport&dq="Jorge+Cervantes"+mylar+paint+foil+mirror
According to that, mylar is better than a mirror due to light lost when traveling through the glass. I suspect that depends on the type of glass and how thick it is. However, the notion that mylar may be better than a mirror is actually new to me. I'll have to check into that a bit more.
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budman111
Well-Known Member
No, no and no. they reflect heat. Mirror is worse.
Darnova
Member
RM3, from the link you provided, "In the end we obtain a reflected wave with essentially the same properties as the incident wave apart from some loss of power, which typically amounts to a few percent for silver mirrors."
If, for example, mylar offers 90-95% reflectance value, how might that compare to, "a few percent for silver mirrors"?
It is interesting. I like it when old myths are discredited (like mirrors are always the best) It helps the grow process. Heck, I remember when some growers believed they needed a UV Blacklight in the grow room.
Budman111, when you say mirrors reflect heat, are you referring to temperature wavelength?
Or were you referring to actual physical heat absorption & reflection?
I think heating & cooling of grow rooms are a different topic than what Apollo11 is asking about. But along that thought, I suspect that mylar attached to a sheet of metal will reflect more heat back into the grow room than mylar attached to wood or cardboard.
If, for example, mylar offers 90-95% reflectance value, how might that compare to, "a few percent for silver mirrors"?
It is interesting. I like it when old myths are discredited (like mirrors are always the best) It helps the grow process. Heck, I remember when some growers believed they needed a UV Blacklight in the grow room.
Budman111, when you say mirrors reflect heat, are you referring to temperature wavelength?
Or were you referring to actual physical heat absorption & reflection?
I think heating & cooling of grow rooms are a different topic than what Apollo11 is asking about. But along that thought, I suspect that mylar attached to a sheet of metal will reflect more heat back into the grow room than mylar attached to wood or cardboard.
RM3
Well-Known Member
No myth to this lol been doin it for years
Darnova
Member
Well, based on my resent research, the reason why manufacturers of newer LED systems are going "full spectrum" for cannabis is because they've learned that the plant uses a lot more visible light through it's veg & flower stages than previously believed. UV dedicated light represents a truly minuscule portion of the "violet" light most used during the vegetative process. And too much UV is actually detrimental to plant growth.
In other words, what I'm reading now is this...
2700k light for veg, then switching to 6400k light for flower is old & busted.
Full spectrum 2400k to 6700k for both veg & flower is the new hotness.
I'm not standing by that theory, only saying that it's what a lot of pro growers & LED companies are moving toward.
As for mirrors v mylar, I had researched (many years ago) that a common silver mirror (with thin clear glass) provides about 97-99% reflectance value. If that holds true, then technically mirrors are a better reflective material. Of course, working with mylar is in every way a whole lot cheaper & less hassle to work with. I guess what I'm interested in is if new information shows that common silver mirrors actually only have <95% reflectance value. If that holds true, then I can see how mirror-covered walls would be in no way beneficial compared to mylar or Foylon.
RM3
Well-Known Member
Perhaps take a moment and clic my Leprechaun sig link, I think you'll find it interesting and note I use white paint and actinic bulbs
