More Reflective? Tin Foil Or flat White Paint?

TeaTreeOil

Well-Known Member
Corrosion decreases reflectivity, anodized prevents this, so it does help in the long run. Glossy paint has a higher specular intensity, going in the direction of, but not near to Al. Maybe with special paint, or titanium dioxide, silver, or gold reflectors....

I don't know if diffused light is best for paints. They seem to all go towards the bulb(s), so the best complete reflection/replication of that light would seem to be the best attractor and have the best benefit. Al does this better than white house paint. If you paint the area in several coats of titanium dioxide I've seen charts stating over 100% reflectivity(it 'glows' from 0-500~550nm), dropping to 98% or so around 700nm, and even more afterwards.

Has anyone ever tried coating aluminum foil or sheet with titanium dioxide? Or another chemical like magnesium fluoride?

Aluminum foil as a reflector might be a bad idea for HPS(+1000C arc or so?), or other HID(more of the same) lighting. But I think for CFLs that operate under 130F or so normally.. add a fan... it's probably really beneficial, and the fan will divert a lot of the heat. Any generated heat will keep it dryer, and Mary loves this.

Begs the question how a well-reflected lower-powered set-up could compare with a higher powered set-up with poor or no reflection.
 

onenumcat

Well-Known Member
Corrosion decreases reflectivity, anodized prevents this, so it does help in the long run. Glossy paint has a higher specular intensity, going in the direction of, but not near to Al. Maybe with special paint, or titanium dioxide, silver, or gold reflectors....

I don't know if diffused light is best for paints. They seem to all go towards the bulb(s), so the best complete reflection/replication of that light would seem to be the best attractor and have the best benefit. Al does this better than white house paint. If you paint the area in several coats of titanium dioxide I've seen charts stating over 100% reflectivity(it 'glows' from 0-500~550nm), dropping to 98% or so around 700nm, and even more afterwards.

Has anyone ever tried coating aluminum foil or sheet with titanium dioxide? Or another chemical like magnesium fluoride?

Aluminum foil as a reflector might be a bad idea for HPS(+1000C arc or so?), or other HID(more of the same) lighting. But I think for CFLs that operate under 130F or so normally.. add a fan... it's probably really beneficial, and the fan will divert a lot of the heat. Any generated heat will keep it dryer, and Mary loves this.

Begs the question how a well-reflected lower-powered set-up could compare with a higher powered set-up with poor or no reflection.
that's very true...and a really great point. how can you get 'hotspots' from a source that produces such a small amount of heat??
it's not like a magnifying glass!! lol it doesn't refocus, it reflects...big difference, right? if foil only has light to reflect...will it still produce heat? I think it won't/can't...as I said before, 'light' doesn't actually produce the heat, the infrared radiation does, through friction. flouros, probably, emit little or no infrared waves...cuz not all spectrums of light contain infrared or in quantities associated with 'heat'.
 

onenumcat

Well-Known Member
so, I found this niffty chart that shows all rays from the sun, including a light chart...just for info

 

needhelp

Well-Known Member
damn... after sparking something up... your chart is very confusing... all i see is colors, words and numbers... just can't put it together...maybe nextime
 

Brick Top

New Member
that's very true...and a really great point. how can you get 'hotspots' from a source that produces such a small amount of heat??

Ask yourself why someone gets hot spots using aluminum foil?

The answer is unequal light distribution/reflection directing more to one or some areas than to others.

Regardless of what type of lighting you use you want the most equal distribution/reflection of light as is possible to best cover all your plants as much as they can be covered with light. So while you may not risk actual hot spots using aluminum foil with CFL’s you still risk uneven/unequal light distribution/reflection and if so that means some areas will receive more light and other areas less light and the plants or parts of plants getting less light will not get all they could otherwise get and maybe not all they need especially since the person is using CFL's which to not put out light like HID lighting.

So while you may not be risking hot spots you will be risking low light distribution/reflection areas. Not a danger like hot spots but not optimal conditions for plants either.

When it comes to equal light distribution/reflection that has pretty much been figured out years ago so I just do not see any reason to try to reinvent the wheel. Reflecting/distributing light of any kind is basically the same and you want the same thing from it. And that is the most equal and even coverage of light that you can attain regardless of the source of the light.
 

I.AM.WEASEL

Active Member
Tin foil IS SHIT FOR REFLECTING!!!! its a fire hazard and causes hot spots. the Aluminium molecules turn the light into internal energy.. and thus light is lost..... flat white paint all the way trust me!!!
 

onenumcat

Well-Known Member
Ask yourself why someone gets hot spots using aluminum foil?

The answer is unequal light distribution/reflection directing more to one or some areas than to others.

Regardless of what type of lighting you use you want the most equal distribution/reflection of light as is possible to best cover all your plants as much as they can be covered with light. So while you may not risk actual hot spots using aluminum foil with CFL’s you still risk uneven/unequal light distribution/reflection and if so that means some areas will receive more light and other areas less light and the plants or parts of plants getting less light will not get all they could otherwise get and maybe not all they need especially since the person is using CFL's which to not put out light like HID lighting.

So while you may not be risking hot spots you will be risking low light distribution/reflection areas. Not a danger like hot spots but not optimal conditions for plants either.

When it comes to equal light distribution/reflection that has pretty much been figured out years ago so I just do not see any reason to try to reinvent the wheel. Reflecting/distributing light of any kind is basically the same and you want the same thing from it. And that is the most equal and even coverage of light that you can attain regardless of the source of the light.
every word true and correct, until the very end...the wheel has been reinvented...it's called flight. and things figured out long ago...are constantly being rethought, reconfigured, redesigned, reinvented and redone...thats a lot of 're', lol. just look at the train...from steam, provided from diff sources ie; wood, coal, ethanol, and who knows what else(thats called a redesign), to diesel, to electric, to electromagnetic(termed Maglev for magnetic levitation)...if those ppl, who have made those...changes had thought like you're doing now, we'd all be pushing wheel barrows! some ppl like to think 'outta the box', it's the 'mother of all invention'.
but you're not incorrect, I just disagree with the way you're thinking...
Personally, I use a light mover, so don't have that problem...by the way, I concived, designed, and built it myself...it is revolutionary, imho.

see the link to my circular light mover here;
https://www.rollitup.org/grow-room-design-setup/155955-wind-powered-rotating-dual-hid.html

or videos here; http://www.youtube.com/onenumcat
 

closetkiller

Well-Known Member
:blsmoke:i make light hoods for my self and seveal friends. all are aluminum, tried anodized and high gloss white. the white works much better and does not get as hot.
 

onenumcat

Well-Known Member
would painting a reflector white instead of using the stock dimpled aluminum give better reflectivity?
see, all the ppl who said 'white is more reflective' are gonna tell you yes. imo, it's no, otherwise, the manufacturer wouldn't have gone throught all the trouble, time, and expense to dimple it. those dimples, refract, diffuse, light...and heat, so it isn't refocused to one spot, hence the name 'hot spot', they would have just painted it white, which is much less trouble, takes less time, and is much, much cheaper to do!!!!!!!! this, however, is only true if the manufacturer intended the unit to be used for growing or outdoors. the majority of indoor, home use primarily, not a gymnasium or a factory, hoods/reflectors are white. this is because our eyes are too sensitive to take the brightness provided by dimples, dulled, burnished, scored, or similarly unshined aluminum or aluminium for you brits. such lighting is generally positioned above our heads, but not very high. imagine, if every time you looked up, in your home, you got blinded! that wouldn't apply in a gym or factory...the ceiling is not 8 ft high...more like 15-20, idk, really, how high, but much higher. you think they paint the light reflectors in a football stadium white, on either side of the atlantic?? you think big green house companies use white hoods??? the dimpled, etc. hoods are designed for outdoor, large areas...and indoor/suplemental lighting, including botanical uses...I'm done here.

plain foil is never 'better' for your grow, than flat white paint. the title of this thread, however, never asked the question that that answer pertains to....any 'mirror' surface reflects more waves, which light is, than a white one, period.

if you take a look at all, four pages, of the light reflectors at this popular garden supply site, none are white on the inside and most, if not all, are textured in some way...and they all say 'more reflective than white' and 'duffuse heat...blah, blah, blah'.
http://www.littlegreenhouse.com/accessory/lights.shtml
unsubscribed
 

Brick Top

New Member
every word true and correct, until the very end...the wheel has been reinvented...it's called flight.

That depends on how you look at it. Airplanes rely on wheels so the wheel itself was never replaced or reinvented by airplanes it was just incorporated into airplanes.


Even helicopters and vertical takeoff and landing aircraft have wheels. Trains run on steel wheels. Cars definitely run on wheels.

The wheel itself was never really reinvented but instead incorporated into newer designs of various things.

Materials wheels are made of have been improved on and they are no longer made of stone or wood but they are still wheels.
 

Brick Top

New Member
would painting a reflector white instead of using the stock dimpled aluminum give better reflectivity?

My opinion is that dimpled aluminum would be better at distributing light over a broader/wider area than a flat piece of aluminum or some other metal painted white.

In the case of straight or direct reflection I guess it is possible that white would reflect better but dimpling spreads out the light and white alone cannot do that.

Maybe the better question to ask would be would a dimpled hood that is painted white be better than a plain aluminum dimpled hood?
 

onenumcat

Well-Known Member
That depends on how you look at it. Airplanes rely on wheels so the wheel itself was never replaced or reinvented by airplanes it was just incorporated into airplanes.


Even helicopters and vertical takeoff and landing aircraft have wheels. Trains run on steel wheels. Cars definitely run on wheels.

The wheel itself was never really reinvented but instead incorporated into newer designs of various things.

Materials wheels are made of have been improved on and they are no longer made of stone or wood but they are still wheels.
ok, then use the train metaphor...either way, we've gone past the wheel, why not other things.....

and ...you missed the point completely...I wasn't trying to redirect the topic to aircraft...of any kind, nor cars, nor trains, nor wheel barrows for that matter...

ok, really this time...
unsubscribed sick o this
 

xogenic

Well-Known Member
afternoon folk


i would say use either flat white paint or the insides of crisp packets [the shiny stuff]

tinfoil is a bad idea as it is designed to reflect heat also so can cause either heat spots behind the foli and burn the room down or light concentration on your plants and burn them
 

Brick Top

New Member
ok, then use the train metaphor...either way, we've gone past the wheel, why not other things.....

I don’t want to swerve the thread so I will not say any more on the subject after this but trains run on wheels, just wheels with what may be called lips or edges that protrude and that is not a reinvention as much as it is an adaptation. It just keeps the wheels on the tracks like a pulley is a wheel and it may have a groove or edge/lip to keep whatever runs on it from slipping off, but it is still just a wheel, just one that has been adapted but not reinvented.

The Wright brothers first aircraft hardly resembles a modern fighter aircraft but neither aircraft or flight was reinvented. The first, the aircraft, relies on the very same basic principals but was adapted for better performance and capabilities and the other, flight, remained the same, it is still flight.

Adapting or ‘tweaking’ or improving something or using something for a different purpose than it was originally intended to be used but still retains the same basic design and or function is not reinventing something.
 
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