UVb an experiment

[oldmac]

damn, oldmac. that sounds like a pretty nice little experiment! when does the log start?
-shake

Well first, I need to get 2 more TIs. The only problem is my partner right now, he came up with the idea of using 4, I wanted to take the 2 we have and use a light mover and move the 2 back and forth abt 2' over the tray. I said great to use 4 but when I called TI the only units they have are the new housings and my partner freaked they would look stupid with 2 of the old and 2 of the new, all bolted together. My original TIs are now 1 year old and where the first batch built and sold (they are labeld "pre-production unit"s). The housings where made of stainless steel, the new ones are die formed aluminum (I think) but contain the same diodes. Just need to convince him we can still mount them all together and get over the appearance.

[Rusty Trichome]

Well, been a week with the UV bulb (yesterday) not much visible difference. Will be looking at undergrowth, leaf development, structure and color, internode stretch...

The tray with the bottle is the UVB tray. Each tray holds 6 clones. 3 short one's, 3 tall one's each.
The box describes the bulb, and I keep it about 6-8 inches from the clones. Box says one foot for proper usage on reptiles, but no real way to get it further without raising the CFL's.
6 23w CFL's in each chamber, but the addition of the 23w UVB bulb isn't made-up for in the control batch. (no extra lumens for the non-UVB clones) I went back-n-forth with this decision, so I flipped a coin.

I guess I'll have to work on getting better shots for comparison, but like I said...nothing going on yet.

Often wondered what kind of growth I'd get with a 20k MH bulb I have from my days in coral reefing. But it's a 400w and not too sure I would want to commit to the wattage and heat, if results were sub-par...and supplimental lighting would be out of the question. (heat and electric bill)

OldMac: Tell him it's doubtful Home and Garden will be stopping by any time soon. (or keep him out of the growroom, lol)

[sheist]

My point is.... When everyone figures out that speed (300nm to 400nm) is the only thing good about these lights. The next step will be seeing that the good (speed) don't out way the bad (uv-b). There are much better ways of getting the plants clock moving faster IMO.

heres a curve ball

can anyone try an addition to this experiment if the uv-b light was color screened to filter out the blue? i've dabbled with photography and color gels to filter out certain lights to get that 'perfect' effect in some shoots, i figure the concept should be relative in this particular case.. if this could be accomplished, perhaps we'll be able to see the true effects of uv-b without spectral influence

[MerryPrankstr]

Well first, I need to get 2 more TIs. The only problem is my partner right now, he came up with the idea of using 4, I wanted to take the 2 we have and use a light mover and move the 2 back and forth abt 2' over the tray. I said great to use 4 but when I called TI the only units they have are the new housings and my partner freaked they would look stupid with 2 of the old and 2 of the new, all bolted together. My original TIs are now 1 year old and where the first batch built and sold (they are labeld "pre-production unit"s). The housings where made of stainless steel, the new ones are die formed aluminum (I think) but contain the same diodes. Just need to convince him we can still mount them all together and get over the appearance.

My TI has the main housing and lens bezel made from a hard tough plastic, FWIW, Mac (s/n 70). Did they change the housings again?

M.P.

[Dutch Pimp]

I am very impressed with the SunPulse bulbs that are rated in K temp terms. They make 4 flavors; 3k, 4k, 6.5k & 10k. The 3k is great for flowering but the 10k is loaded with UV.

SunPulse's web site talks about 10k bulbs for the last few weeks of flowering ? Don't think I've heard anyone discuss that concept yet?

[oldmac]

Hey Dutch,

I believe the reason they rercommend that bulb for the last couple of weeks, is that UVb has it's greatest impact (from what I just saw) on trichome finishing. In my experiment wo/UVb trichomes stayed clear longer and changed to cloudy slower without UVb and never produced any amber ones.

Here's my last obsevations, since drying and manicuring;

1) The finished buds have less odor wo/UVb, they lack the sweet/pungent smell that I usually have with WR.

2) Potency seems to be slightly less wo/UVb, myself and a few tasters could tell a difference but it was very slight. Tonto preferred the wo/UVb saying only it was a better overall "to him". Again a product of no amber trics?

3) Finished weight was down a bit, averged .42 grams per plant less wo/UVb. That does not sound like alot but in my SOG grow it equals 2+ OZs for the run.

I'm not going to give up the UVb supplemental lighting anytime soon. It did not do everything I thought it would, but based on just finishing times and wgt differences I believe it is worthwhile.
:thumbsup:

[oldmac]

6 23w CFL's in each chamber, but the addition of the 23w UVB bulb isn't made-up for in the control batch. (no extra lumens for the non-UVB clones) I went back-n-forth with this decision, so I flipped a coin.

I don't think that small a difference in lumens will invalidate the effects of your experiment. If UVb has an effect overall, starting at the veg state, it will have an effect. Good coin toss.

OldMac: Tell him it's doubtful Home and Garden will be stopping by any time soon. (or keep him out of the growroom, lol)

I sorta see his point, we are talking about placeing over $5,000 worth of lights over one grow tray. For that much money they should be aesthetically pleasing.

Are you showing any signs of turning hermie from the aspirin?

[oldmac]

My TI has the main housing and lens bezel made from a hard tough plastic, FWIW, Mac (s/n 70). Did they change the housings again?

M.P.

No they have not, I was guessing the new ones where aluminum, so thank you for letting me know they are now plastic. From what I gathered the originals where stainless, then they went to painted black, same shape but I'm not sure if they changed materials and then the current design.

M.P. you could do me a big favor and let me know what the new housings measure, lip to lip (both directions). Also, if possible the distance from the lip to the glass cover over the diodes. That would give me a chance to prerun mounting ideas, and see if they need to be mounted at differant heights.

[oldmac]

heres a curve ball

can anyone try an addition to this experiment if the uv-b light was color screened to filter out the blue? i've dabbled with photography and color gels to filter out certain lights to get that 'perfect' effect in some shoots, i figure the concept should be relative in this particular case.. if this could be accomplished, perhaps we'll be able to see the true effects of uv-b without spectral influence

Hello sheist, you raise an interesting point about the use of filters. Almost all of the scientific research dealing with plant photosynthesis was done useing filters. A paper done in '98 dealing with pulsing LEDs (5mm diodes back then) used a 668nm LED that showed abt 660nm was optimum for photosynthesis, and got me real excited because they did not use filters.

Here for our purposes it would be difficult to filter blues out since some blue is necessary for plant growth. Also there is a possiblity that some UVa or UVc may be helpfull not just the UVb, and that would be ok by me. We pretty much can only grow with what's available to us. Using an all LED grow light, with and without UVb diodes might be the only method to better define the effects of UVb.

But if someone wants to step up with an experiment using filters, I'm interested.

[oldmac]

Sorry, I just double posted.....had a brain fart apparently.