Does Light Intensity Affect Potency?

Discussion in 'Advanced Growing Techniques' started by FarNorCal, Jul 5, 2010.

  1. I am under the impression (simply because of years of growing under almost every light available except LEDs and the 1500W master blasters) that a 1000W HPS light will produce a more potent bud than a 150W HPS.

    A lot of people want to argue this point, so here it is:

    Given proportionate watts per square foot (lets go with 50W/ft2)

    And using two very different wattages so the difference, if any, isn't subtle (let's go with a 150W HPS vs a 1000W HPS)

    With the same strain, medium, nutrients, and temperatures/co2 (no difference between both rooms as far as the outside factors go)

    Not speaking of yield, bloom time, or ANYTHING ELSE, will these two lights produce the same potency of weed?



    This is not a thread comparing CFLs to HPS, MH to HPS, LEDs to HPS, or any combination of other lighting that will change the control factors. It is to compare light intensity (basically a SINGLE source of lumens intensity). Any post that are blatantly argumentative or spiteful will simply be deleted. Any posts off subject will be deleted.

    So lets hear it people!
     
  2. You are wrong. Again.

    Every single study ever done on the topic points to the same result: UV light increases potency. No other wavelengths of light do. The plant produces more trichomes to protect itself from damaging radiation.

    Light disagreement | Cannabis Culture Magazine
    Pot potency | Cannabis Culture Magazine

    How many more do you want? It explains all of your outdoor examples perfectly, and accounts for the fact that indoors, more wattage does not equal more potency, as EVERYONE has told you every time you post that particular bit of false information.
     
  3. #3 zehn, Jul 5, 2010
    Last edited by a moderator: Jul 5, 2010
    IMO, it really shouldn't change the potency very much. The 1000 watt will produce much more dense buds, and more uniformly due to its massive penetration power as compared to the 150 watt light. Denser buds COULD fool you into thinking that your pot is more potent, simply because a given nug will have more bud on it period (though this could easily be circumvented by simply weighing out the same amount from each batch).

    If you really want to artificially up the potency of a given strain, I suggest you look into UV lighting. This article: Marijuana THC will give a good rundown if its benefits, along with a ton more information than you probably want to know about marijuana.
     
  4. #4 iampolluted, Jul 5, 2010
    Last edited by a moderator: Jul 5, 2010
    if you pull a clone from a mother, and put them in to flower in the situation you listed the potency will not change....it can't all other factors being equal. genetics are genetics, and light doesn't have the ability to change them. simple logic. besides, it's not the bud size you are comparing, that's irrelevant, it's the trichomes that determine the potency, and if cut at the same state of development the quality will be equal.
     
  5. Trichomes do not determine, nor are they a guarantee that a plant is more potent. I have grown Ruderalis which tested to be less than 1% THC which was heavily coated in trichomes, yet a land race Thai which had much lower density of trichomes tested to close to 20%.

    Pot potency | Cannabis Culture Magazine

    Trichomes - the source of Magic - Woyano

    As stated in an above post, UV light will increase trichome production, however it does not prove this makes a plant more potent. There are many studies into this presently, none of which show any factual evidence that it makes a plant more potent.

    IMHO, light has little to do with potency as well. I can grow buds just as dense and full of trichomes under flouros as I can under HID. Have not worked with LED's yet b/c the cost far outweighs any benefit at this time IMO. However, I would have to say one can produce just as good of bud under LED's as they can other types of light sources.
     
  6. That highly depends on what you consider potency.

    More trichomes = more cannabinoids. That is indisputable, and also what I would refer to as potency. It requires less of it to achieve the effects it has, whatever those effects may be.

    THC content is near completely genetically-determined, and I have never read any reliable method of changing the cannabinoid profile of buds except for altering when you harvest, which can only results in lower THC than the maximum possible with whatever strain you are growing. I would refer to this as "THC content".

    The conflation of THC content and potency occurred through the last 40-50 years since people thought THC was all that mattered. It has since been discovered that many cannabinoids alter the subjective effects of cannabis, not just THC. Therefore, it is not particularly accurate to make THC content and potency synonymous.
     


  7. Correct. Exactly correct. It is even known that various terpenes also have clinical value to the effects of THC and other cannabinoids.

    I have found no way to alter cannabinoids, nor increase THC, however you can alter terpenes with environment, just as you can alter phenotype somewhat with changing the environment.


    Lighting, IMO has no direct effect on anything other than plant growth, and flower development. Potency is mainly determined by the strains genetics. Phenotype is a result of the combination of genetics and environment. I have yet to see any direct connection with environment, and/or lighting, increasing potency.
     
  8. #8 FarNorCal, Jul 6, 2010
    Last edited by a moderator: Jul 6, 2010

    The reason why you are on my ignore list is because you are a condescending asshole. I'm sorry you can't be nice to people.

    Trichome quantity does not denote potency, trichome quality does. Chemistry bro.

    I'll read up on your articles, but pull that corncob out of your ass and start being nice.;)

    [Name calling does not fly here. If you have them on your ignore list, ignore them. -FW]
     
  9. I see what you guys are saying though..

    Just because a bud is more dense doesn't necessarily mean that it will be more potent.

    Does the 1K bulb have a greater UV output than the 150W due to the upped wattage? Not a different spectrum, but a greater amount of UV radiation emitted?
     
  10. Uh, sorry, but no. You started this all off by being incredibly arrogant while being wrong and saying that everyone I and other people knew must just be happy with our sub-par weed that isn't made uber dank since we don't have 1500W HPS lights.

    Perhaps you should read my post where I explain what increasing numbers of trichomes do. More trichomes = more cannabinoids. If you take two buds from the same strain, the one with more trichomes will contain a greater proportion of cannabinoids by weight, which is an important metric even if you want to call it something other than "potency".

    HPS lamps effectively emit no UV radiation, therefore increasing the wattage does not appreciably alter the amount of UV light getting to the plants. To get a decent amount of UV indoors, you generally need to buy special UV-emitting lights.
     
  11. metal halides give off uv radiation.
     
  12. In theory. In practice, the glass for MH bulbs is usually UV shielded so while the bulb is technically emitting UV, it is unlikely any large amount will reach your plants. You can probably find ones that aren't shielded if you look, though.
     
  13. #13 iampolluted, Jul 6, 2010
    Last edited by a moderator: Jul 6, 2010
    everything i've read says they emit an undetectable amount (only because it's out of the spectrum we see), but it's there. most companies try to shield them as much as they can but it's does produce it. have you ever looked at a metal halide for a minute then looked away? been snow blind from it? that's the uv fucking with your eyes...halogen bulbs produce a lot of uv....leds produce no uv at all.
     

  14. That's not the "UV fucking with your eyes". Any bright light source will cause that effect. Your eyes adjust to a bright light, and when it is removed from your visual field everything looks dimmer until your eyes adjust again.

    The point is that most MH bulbs do not emit enough UV for it to make any real difference to the plant. The plant grows more trichomes in an attempt to shield itself from harmful radiation. If it is not receiving harmful amounts, it will not have a significant response.

    UV-emitting CFLs and T5s are readily available. If you have a HID system I'd recommend supplementing with those for UV. I've also seen it recommended to only bother with UV in the late stages of flowering where resin production is at its maximum.
     
  15. there is a difference between a bright spot from a flashlight and photokeratitis. some MH bulbs that have been damaged (outer glass broken, and to some people that work under them constantly, like aquarium hobbyists) have been known to do damage to the eye, notably from exposure to uv from the bulb. it's like staring at a hot weld for a few hours. photo sensitive people have to take extra precautions as well.

    if i'm not mistaken or completely fucked up (i'm fried) and retarded, you basically proved his point, and validated it by saying the light can actually effect potency by adding uv t5's or cfl's or even a MH.


    Quote:
    More trichomes = more cannabinoids. That is indisputable, and also what I would refer to as potency. It requires less of it to achieve the effects it has, whatever those effects may be.

    Trichome quantity does not denote potency, trichome quality does. Chemistry bro.

    Perhaps you should read my post where I explain what increasing numbers of trichomes do. More trichomes = more cannabinoids. If you take two buds from the same strain, the one with more trichomes will contain a greater proportion of cannabinoids by weight, which is an important metric even if you want to call it something other than "potency".

    Quote:
    Does the 1K bulb have a greater UV output than the 150W due to the upped wattage? Not a different spectrum, but a greater amount of UV radiation emitted?
    HPS lamps effectively emit no UV radiation, therefore increasing the wattage does not appreciably alter the amount of UV light getting to the plants. To get a decent amount of UV indoors, you generally need to buy special UV-emitting lights.
     
  16. #16 Possuum, Jul 7, 2010
    Last edited by a moderator: Jul 7, 2010


    One of many challenges that arise from the ongoing debate of the efficacy of UVB light in cannabis horticulture is that there is little, if any, available lab research to support the theory. I have not been able to find one published scientific study specific to cannabis. Academics are just not pursuing this trial publicly so it seems. If we take the cannabis species out of the discussion and instead focus on trichome development on par with UVB exposure then there is much literature to explore. One will have to do that research and come to their own conclusion as it relates specifically to cannabis.

    That said, there is plenty of academic research that supports increased trichome development of many plant species as a result of increased UVB light exposure. Trichomes are not unique to cannabis as many plant species produce trichomes. It’s the Delta-9 group that makes cannabis special to us. So, the academic jury has voted and said “yes”, increased UVB light will increase plant trichome production.

    Now we have to break that down to determine if the increased trichome production increases trichome potency. Without sophisticated laboratory equipment to test the Delta-9 group it’s a very subjective guess. I’ll digress a moment and say that all of the seed companies that publish THC levels are either paying money to a lab to definitively test the THC levels or they’re simply guessing or offering subjective opinion. I'm opting for the latter as it is a very expensive laboratory effort to actually test the Delta-9 group.

    One thing is absolutely certain. Exposure to high levels of UVA, UVB, or UVC are detrimental to human health and great care should be used when using any source of intense light or UV light in the grow space. One needs to protect the eyes as that is the most sensitive area to be damaged if the UV light is too intense.

    Having explored this topic is some previous threads I am of the mind that if the grower will exploit every paramater available to him/her as a grower, exclusive of adding UVB light source, and select genetics that are proven to be high yield, high potentcy plants, then the addition of UVB is probably inconsequential. There are only so many miles-per- gallon that can be obtained, so-to-speak. Adding UVB light in a grow environment that is less than optimized and growing a strain variety of cannabis NOT known for it's potentcy will not significantly increase the final potency outcome. Why bother? Just focus on good genetics and an optimized grow environment. If the yield is high enough then make hash and consolidate all of the available THC in condensed form, smoke it, and be happy with that.

    Peace...:smoking:
     

  17. I vote "yes". I believe there is enough published research regarding genetics, hybridization, and potential crop yield of any plant species to support my conclusion. I think the difference in the light PAR value in your scenario is "yield" only.

    MHO for what it's worth.
     
  18. I'll bold the reason why I didn't prove his point. ^

    That really further proves that the shielded glass is made to block UV. The amount passing through is negligible. If it wasn't, the bulb would need to display that and have a big-ass warning. The government takes ionizing-radiation-emitting devices pretty seriously, for good reason.

    A fluoro tube would kill you if it didn't have its phosphor on it... that's not really evidence of them emitting UV, though. The way fluorescents work basically prevents them from emitting any UV unless they explicitly want them to. You can buy reptile aquarium T5s that emit about 10% UV. I may experiment with one of those in my grow that's going on right now.

    Not to mention, his original argument was that a 1500W HPS would make WAY more "dank" buds than a 600W HPS, which is lunacy. HPS really doesn't emit hardly any UV in the first place even.

    edit: and for the aquarium workers, looking at any intense light source repeatedly will damage your eyes over time. Even with uv-blocking sunglasses, staring at the sun is a really bad idea.
     
  19. #19 bulletcatcher, Jul 7, 2010
    Last edited by a moderator: Jul 7, 2010
    Most of my interest in growing with UV comes from a few articles I've seen, as well as the reports I always hear about the potency of cannabis from high-UV areas of the world.

    edit: I agree more weed needs to be lab tested, too. We also need to abandon this "THC only" mindset as well. The other cannabinoids seem to make a big difference. It's not really an expensive process, though. Most of the cannabinoids have very different vaporization temperatures, so it's pretty easy to separate them on a gas chromatograph. If you want to know about some of the minor constiuent ones that will get clouded by the more major constituents with similar vaporization temperatures, or the proportions of THCV/CBDV, then it gets harder since you have to move up to mass spectrometry.
     
  20. TY and I agree 100% with your post. I say add UVB if that's what one wants to do, be safe about it, and if the potency increases, mo the betta.

    P38
     

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