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Has anyone experimented with reflectors? If we're using the dome architecture for our indoor gardening/hydroponics, we can line the interior of the dome with a reflector like aluminized mylar (or aluminum foil if mylar does not prove to be affordable) and use fewer lights. The hyperbolic nature of the dome interior will serve to focus and direct the light onto the plants.

Offered by Roger.

I've recently read an article in a newspaper about a new kind of plastic-like foil, called Mylar. This foil is supposed to be capable of reflecting light by 99%. They say that if you would use this as a mirror, you'll be able to see yourself about 29% sharper than with a conventional mirror. Some company called 3M has developed this and is going to bring this on the market somewhere next year. I'll certainly look out for this.

Offered by Jeroen.

Rolls of Mylar are expensive, get trashed quickly, and actually return less light than does flat white latex paint. While not intuitively logical, this has been measured inductively by selective growers; flat (not glossy) white paint returns 98% + of the light it catches. The mylar does not stay perfectly smooth, and tends to refract light in too many directions. Silver-backed mirrors, on the other hand, have a hard surface and can be better controlled for reflective shape (which should be parabolic). The mirror or white paint will return the light for you; the curve will concentrate and intensify it.

The best measure of how effective a given shape of reflector is, is the intensity of candle power per square foot that it produces. High light plants (anything which needs to flower and fruit) do best getting at least 50 lumen per square foot. There are meters which can be purchased which will measure your actual luminosity - no need to guess. Go to a nearby hydroponics store for one, or look up hydroponics sources on the Web. With a flexible, flat mirror, you can keep adjusting the curve of the parabolic surface and measuring your actual results to find where you produce the greatest intensity of reflected light.

Offered by Jenny.

Mylar around a room does increase the light on the peripheral plants and it works to some degree (certainly cheaper than a bulb as an example) and that was how the snaplite got from 4 sq. ft. to 9 sq. ft. The 3M website sounds extremely interesting and 3M knows what it is doing! It does look like this product diffuses light instead of focusing it in the examples 3M cites. Plants need focused light. It's entirely possible this product can do that as well.

Offered by John.

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