why is tinfoil (al foil actually) considered a bad reflector for CFLs ? - dull side vs shiny side; hey, a CFL is a diffuse source, how can a focused bright spot occur ? - heat reflection/increase: huh, heat is merely a part of the the frequency spectra being reflected so does mylar, panda plastic, or flat white paint NOT reflect that spectra ? data ? if anything the higher thermal conductivity of tinfoil should serve to reduce temps (given equal venting) comments solicited (reading the threads is a true PITA given all the contradictory opinions)
You'll find that a TON of information that floats around these forums is from hearsay. Nobody actually knows. One person said something that was half-way logical and everyone goes with it. As far as testing these theories, you won't find much. I thought about doing it, but I don't exactly have the materials yet. I should though... to see if any of this shit is close to right.
Greenthumb: says who? That's the same BS they gave me a couple of years ago when I started thinking about the same problem. So who are you going to believe, a stranger of your physics teacher? It made sense to me. I was growing with a couple of Aerogardens and I cut recessed lighting lenses for florescent fixtures down to size and glued Mylar over them. The trick was aiming them at the right angle so that you redirected the light back up to the lower shaded portions of the plant. Let me end the argument this way: I got buds all the way down to the planting deck. My sainted physics teacher was right, the angle of incidence does equal the angle of refraction. Go for it. Hank
thanks for the comments guys tinfoil it is, also on the top of the 5 gal pot underneath the plant converted a floor fan shroud into a 26" parabolic with 7 23W CFLs (in a rural part of central america so my construction materials are quite limited) the plant is LSTed so it is actually within the bulbs I'll look for bigger/warmer bulbs next time I go out
tinfoil creates hot spots and its a pain in the ass to work with. If you must, it will work, but mylar and other reflective material is better because it is more malleable and won't hold onto its wrinkles. You are better off making a reflector out of a piece of polished aluminum. At least it will be more durable. What do you plan on mounting the tinfoil to? Cardboard?
I agree tinfoil is a pain, but its all I've got on hand and it is worse than it sounds, I live 150' from the ocean so the tinfoil must be replaced every month or so no mylar here, or even white plastic
Foil does not create "hot spots" that will burn your plant, it simply is not nearly as reflective as other materials you could use. A foil reflector is definitely better than no reflector at all. But, flat bright white paint and mylar reflect light much better.
Toastybiz: aimed Mylar reflectors can work great. The operative word here is "aimed." Aerogarden sells Mylar screens but they just hang straight down if you 'aim' a reflector up you can do wonders with the light God gave you. 2mm Mylar is highly reflective and tough. Don't waste your time with the thinner Mylar. Hank
You're preaching to the choir, man. I was advising against aluminum foil made for cooking, not against mylar -- that's the good stuff.
Hey folks: I used aluminum foil for years, the shiny side to the light, and it worked pretty well but I really think there's a better way. I've always used florescent lamps. T-8's originally, flat CFL's in my Aerogardens and now T-5's over my bubble tubs. I think you get a better reflective surface from Mylar, especially if if it's mounted on something solid and aimed to reflect the light back up to the lower portions of the plants. Where I think it really proved itself was with my Aerogardens because I got buds all the way down to the planting deck Don't forget the angle of incidence equals the angle of refraction. For what it's worth, a pen pal friend of mine in northern California was doing the same thing and I got him to start 'aiming' his panels, not just hanging them vertically on the wall and he had the same experience I did, more buds, lower. No need for additional lighting and the expense and frustration that goes with it. He just mounted his on cardboard panels. I mounted mine on sheets of plastic because I'm paranoid of fire, but his results were the same. You might want to try it. Hank
I have tin foil, and foil tape next to the mylar i bought at walmart for $1.99 and with the light on it there is an undeniable difference. Why waste any time on tinfoil when you can buy "mylar" at walmart in the camping section (fire safety blanket in a little green box) by all the coleman stuff? one little box of the stuff is enough to cover a whole 30 gallon rubbermaid container if you use double sided tape to stick it on there.