New CONTROVERSIAL studies about UVB exposure and yield

Advanced Techniques
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7 posts were merged into an existing topic: To flush or not to flush?

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UV not increasing yield shouldnā€™t be controversial, at all. UV, and even heavy blue light will decrease yield by down-regulating auxin production. Basic CMH vs HPS argument.

And failing to see an increase in cannabinoid content is, sort of, missing the forest for the trees. There are other peer-reviewed studies that have shown an increase in secondary metabolites in all sorts of plants exposed to UV, compared to their controls. I think limiting their scope to cannabinoids hurts their case

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Look at the color of your light vs the one I posted, yours is purple, (true uvb led diodes are about 18$ a diode) the florescent that Iā€™m using is blue, like a tanning bulb.

If I were to hold my arm up against my uvb bulb for 15 secs right up against it, I would have a really bad sunburn. Iā€™ve done it before by mistake. (The bulb is cool to the touch)

Black lights (uva) might help a little but its marginal compared to uvb. Like 0.0001 difference between using uva and not using it.

Throw a uvb in there and youā€™ll notice a difference.

This is wayyyyyy better than uva
https://www.chewy.com/zoo-med-reptisun-100-uvb-compact/dp/126581?utm_source=google-product&utm_medium=cpc&utm_campaign=hg&utm_content=Zoo%20Med&utm_term=&gclid=CjwKCAiA5t-OBhByEiwAhR-hm7Rp4kpxQZKRypn1bRFCiFJjNN1ur9TxgMxVHjXhO8JEdXgG4eXENBoCA-kQAvD_BwE

Heard about UVB lights being used back in 2003
(Ignore the inda-lights ads, this video is a repost)

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UVB is dangerous and you canā€™t use it for long. It does provide more Effects but itā€™s not worth it imho.

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Thats why I run it for a few mins a time per hour.

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iā€™ve been thinking and reading a lot about uva/b and made this conclusion, but donā€™t feel like copying it here. someone else please look at the thought process and see if it makes sense please.

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If the paper was based on LED UV having no effect there is your answer.
I think it was also said that LED diodes suck ass for UV output.
Maybe they would do better if you bought the cutting edge chips but that will be $$$$.

I agree with those that said pulse lighting is best for UV.

Also running UV for long periods or all day can harm plants or slow growth.

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I read it, but I donā€™t understand your goal.
Are you asking about output?
Like PAR.
I looked at the light you linked and saw nothing about how much UV output it has.
Everything about the spectrum but nothing about PAR output.

If you are talking about spectrum/color the wider the better.
Also the light linked looks like it is a very narrow band of UV for a certain reason.

365 nm nothing above nothing below, seems a bit empty to me.
But if they do this for a specific reason, I have not heard it as of yet.
Not sure what they are up to with a narrow spectrum band such as this.