I’ve heard of lightbulbs that are supposedly “full spectrum,” are supposed to better mimic “natural” light (or something like that), and are supposed to be the cat’s pajamas. Mostly what I find when I search are places selling 'em, which isn’t quite the sort of unbiased source of info that I’m seeking.
Can anybody fill me in on what they’re supposed to do, what they do do, and whether they are really just a scam (i.e., maybe my GE Trimline T8 already gives me a full spectrum of light)?
These kinds of lights are used for growing plants.
A blue spectrum light (metal halide) is used for vegetative growth of plants. A red spectrum light (HPS sodium) is used for flowering plants. When combined (full spectrum), you get the best of both worlds, and if done properly, you can get those giant tomatoes you’re always hearing about.
I think I am correct on this. When matter is heated it can cause electrons to jump to higher energy levels. When they naturally jump back down they release light of a wavelength that is dependent upon the atom. This is how they can tell the content of stars light years away. The same thing happens with the bulb filament. The spectrum depends upon what the filament is made up of, and what the coating in the bulb is. My guess is that they coat the bulb with a materal that absorbes the light and reemits it over a broader spectrum.
No, I think we’re on the same page now: I have a shelf at the office with a fluorescent light attached underneith. It is obnoxious, sort of, but the extra light is good. I was thinking that if these full spectrum bulbs were the shizzle, as the kids say, it might be worth plunking down a couple extra bucks to have a bit 'o the natural light in this dreary place.
Full spectrum bulbs are an absolute necessity in herpetology. Most reptiles are dependent on the sun for heat and the ultraviolet rays for proper metabolism. Regular lightbulbs are lacking in the ultraviolet range, and hence lizards kept indoors (mine are bearded dragons) who don’t get the benefit of a full spectrum bulb can have metabolic and bone problems.
Are they useful? That depends on what you’re using them for. For lizards who need the exposure, the answer is a definite yes. For plants, the answer is maybe, but they do just fine with sunlight through the window. If someone’s trying to sell them to you based on supposed health benefits to you, the answer is hell, no! Humans can get a long just fine with no exposure to natural light, although at least a few minutes a day are a good thing.
BTW: My pet store sells 150 watt full spectrum bulbs for $10. Did you see any better prices in your internet seraches?
$17?? Egad! Well, at least now you know that if you must have a full-spectrum bulb, you can trot down to the local pet store and get one for almost half the price. If you go to a reptile show, you can get them for $6 or less. Incidentally, they fit in standard light sockets and come at all levels of wattage.
I’ll ignore the lizards and <ahem> hydroponics and hit on the other reason: color rendition.
Incandescant bulbs put out a heavily red-orange-yellow color spectrum. Fluorescents are heavily green and blue. With special phosphors, you can obtain a pretty even color spectrum in fluorescents.
As this closely mimics natural sunlight, FS lamps are in demand by anyone whose livelyhood is based in color - graphic artists, painters, clothing designers, etc. A popular brand of these is the Ott-Light.
Two winters ago, my indoor herb garden looked like someone called in a napalm strike. The only survivor was a sage plant crouching in the corner and watching me with a wary eye.
Last winter, full spectrum, baby, and the garden stayed healthy throughout. The sage still doesn’t completely trust me, but we’re working through it with therapy.
No doubt, but after a quick look through the Internet that the OP inspired, people are claiming that full spectrum bulbs prevent cancer, cure depression, stop glaucoma and make you more attractive to the opposite sex AND they’re insanely overpriced. Is there nothing that charlatans won’t make a quick buck off of?
Personally, I don’t buy any of their claims, but it IS possible that it might have an effect on seasonal affective disorder. I still wouldn’t spend more that $10 for a bulb for that purpose.