Well that's great and all that you have friends, and I'm not even saying it's 100% proven idea...just that it will be a neat idea to play with. And apparently he did too.
Ok...well this is just turning into a big pissing contest. But, I would like to know if the sun puts out UVB and we can feel the effects on our skin (i.e. sunburn), that means the plants can feel it's effects as well. You say it stunts growth...explain the 8-14 foot monsters these outdoor growers produce.
There was no "bombs" dropped here. You didn't say anything relevant, sorry to say. That pdf from the CA science fair essentially says "I exposed plants (Which aren't named in what you gave me.) to different amounts of varying UV radiation (Which are not qualified.), and the UVB ones grew less (Which means nothing without a lot more info.)", it also doesn't say how the plants were grown, or anything that really is helpful. The rest of your articles just talk about UV in general; which in no way reinforces your point that UV=bad for plants. Sure overexposure is bad, I've seen what too much can do. However, I have seen enough solid grows that kept right on running without that pesky UVB killing everything or killing their usual yields. Hell, it may have just been wishful thinking, but it even seemed "stickier". Not saying it's conclusive; but it's, at worst, inconclusive.
You don't understand that a 420nm wavelength of light from the sun is the EXACT same thing as a 420nm wavelength of light from a bulb, do you? A photon at a certain wavelength, is a photon at a certain wavelength; plain and simple.
You also said UVB is "Violet" light, which it is not; "Ultraviolet" means "beyond violet". Much like "infrared" means "below red". They are not assigned colors, because they are beyond the visible spectrum. If UVB was "violet" as you say, we would be capable of seeing it.
I have to disagree again. "A sunbed (British English), tanning bed (American English) or sun tanning bed is a device that emits ultraviolet radiation (typically 97% UVA and 3% UVB, +/-3%)". Courtesy of http://en.wikipedia.org/wiki/Tanning_bed Until recently, UVA was considered "safe"; so it's been a popular choice in tanning beds, as UVB has long been known to cause cancer in humans with extensive exposure.
I have 5 plants growing, 3 in mid-late flower and 2 seedlings(3 days old). I have around 350 actual watts of light.
I seem to recall Hopey saying that wasn't enough light in the very first post made in this thread. Nobody contested the act that the amount of light is too little, you did go on talking about UV though. That's why we are where we are now.
CFLs, a waste of time?..that's just not true.
It is for the common cash cropper. Cfls are good for newbies, yes. But they're also proven to show slow growth on plants, and less yield.
