LED vs HPS?

[mauricem00]

Guessing you mean Induction lamp... Good tech but you would need to pull equivalent HID wattage in order to keep up in terms of yield, although I found quality was better using induction, the let down was Chinese crappy ballasts and weak application of the Phosphor coatings (had some where the coating fell off) poor manufacturing being the weak points here.

OP will definitely get more bang for his buck using 1 of the 3 Double ended offerings you have posted here.

good tech. poor execution and T5HOs have passed induction light in efficiency.you are right about the ballast and the coating. they were a hot grow light for a while but now just another passing fad

 

[MichiganMedGrower]

a goo

google search indicates that Phillips 3100 is a high cri metal halide bulb. life expectancy and output are the same as a CMH bulb. the 4200k cmh seem to have a more balanced spectrum but phytochrome responds to a wide spectrum of orange and red light and chlorophyll A actually emits deep red light when exposed to violet light apparently the S2 to S1 transition drives photosynthesis and the energy for S1 to ground state is waste emitted in the form of light. apparently deep red is only needed in large amounts if you light can't produce violet light

I found the chart but not the article. Here is the link.

https://www.cycloptics.com/sites/default/files/GB USU Spectral Characterization link.pdf

 

[MichiganMedGrower]

The Guy is John Berfelo he isn't exactly a scientist in a real lab but seems to have his stuff togeather the video is here

If you do your research you will see that CMH, MH & HPS have the correct spectrum and then some. They tend to waste 25% of the power used creating spectrum the plant cant use. Simple reason LED's are better is that you can customize the spectrum and lower that 25% loss to almost nothing and just produce a spectrum the plant can use. CMH has better resin production because of the UV-B it produces and you can add a UV-B fixture to your DIY COB setup to cover the UV-B. No clue why the LED manufacturers are not doing this themselves. Closing MY LED troll (not a troll just info but sure someone will disagree). A proper led will use half the power of conventional lights with the same production weight wise and resin wise if you supplement the UV-B somehow. So DIY COB with a UV-B lamp you can equal the production of traditional lights with less heat less power and longer lifespan of the light. LED are not really better than traditional lights per say they are just more efficient so cheaper over the long run and give you the ability to customize the spectrum. I like the idea of the UV-B lamp being separate so i can control it's on time. CMH basically is constantly stressing your plant by literally giving it a sunburn for the duration the light is on. Seems lowering the duration of UV-B exposure during the light cycle would produce less stress and still rase resin production.

Excellent post. I agree with all of this. The only problem for me with LED is I need the heat from my hid bulbs in winter in my old house or I would have to ruin my efficiency with more heating for my room.

 

[Morth]

Guy is long winded and I wouldn't really say it's a legit scientific experiment. On the other hand it's what we have to work with and at least he is trying.

You want UV-B not UV-A http://hightimes.com/grow/grow-hack-does-uv-light-increase-cannabis-potency/ you want it to damage the plant and for the plant to produce sunscreen/resin to protect it's self. Not sure that haveing constant UV-B bombardment during the light cycle is a great idea though but i'm less of a scientist than John Berfelo. Actually no where near that guy i'm a super noob in comparison.

 

[mauricem00]

these are interesting discussions but in the end our plants tell us what they need. these just help us to know what to test in our gardens.from that chart looks like cool white LEDs would be the best LED option for growing plants but with specialty bulbs T5s come the closet to natural sunlight

 

[MichiganMedGrower]

how can all 3 bulbs have the correct spectrum for cannabis when they all have radically different SPDs?COBs produce a very narrow spectrum of blue light and plants use broad spectrum blue light. video was interesting but a little long winded.sunlight only contains 0.15% UV-B and UV-B damages plants and slows growth. UV-A increases THC content without slowing growth or damaging plant but LEDs can not produce UV-A or violet light efficiently so bulbs would need to be added to a COB to get the best flavor and potency and mixing bulbs and LEDS can be a bit of a nightmare since T5s need to be much closer to the plant and LEDs need to be farther away to prevent burning.wonder if he used enhanced spectrum horticultural HPS bulbs in his test or just standard street lights

I agreed with these comments but I mixed up uv a and b. You are of course correct about a.

From most comments I have read and the video confirms cob grows more flavorful weed. And cmh grows more potent weed.

I use Hortilux HPS for the added blue but I can see now it is not quite enough. The guy in the vid used a gavita. I believe they are enhanced too.

 

[MichiganMedGrower]

Guy is long winded and I wouldn't really say it's a legit scientific experiment. On the other hand it's what we have to work with and at least he is trying.

You want UV-B not UV-A http://hightimes.com/grow/grow-hack-does-uv-light-increase-cannabis-potency/ you want it to damage the plant and for the plant to produce sunscreen/resin to protect it's self. Not sure that haveing constant UV-B bombardment during the light cycle is a great idea though but i'm less of a scientist than John Berfelo. Actually no where near that guy i'm a super noob in comparison.

The bulb he used has very little uv anyway but it is higher in uv-a. That is the spectrum the university of Utah has confirmed. I thought I had this right but I may have marijuana based dislexia and be reversed.

 

[MichiganMedGrower]

these are interesting discussions but in the end our plants tell us what they need. these just help us to know what to test in our gardens.from that chart looks like cool white LEDs would be the best LED option for growing plants but with specialty bulbs T5s come the closet to natural sunlight

I thought cmh was closest. Looking at spectral graphs I still wonder about the Hortilux 400w blue. That bulb tinted my glasses which does not happen under the cmh 3k.

Uv tints photo sensitive lenses.

 

[mauricem00]

I agreed with these comments but I mixed up uv a and b. You are of course correct about a.

From most comments I have read and the video confirms cob grows more flavorful weed. And cmh grows more potent weed.

I use Hortilux HPS for the added blue but I can see now it is not quite enough. The guy in the vid used a gavita. I believe they are enhanced too.

the first dispensary to open in northern nevada used LEDs to grow some of their plants. they also buy product from commercial growers that use CMH lights and you can taste the difference.maybe they just lack the experience since their grower is a recient graduate whose only experience was growing grapes outdoors but their LED grown house weed does not compare tho the products they buy from commercial growers and the test I ran using COBs produced the same yield (GPW) but lower taste and potency. my summer patio grows ( real sunlight) gave the best taste and potency so I'm trying to get as close to natural sunlight as I can.wish I could use CMH but I just can't handle the heat

 

[mauricem00]

I thought cmh was closest. Looking at spectral graphs I still wonder about the Hortilux 400w blue. That bulb tinted my glasses which does not happen under the cmh 3k.

Uv tints photo sensitive lenses.

if only 1.9% UVA gave that much of and improvement I wonder what sunlight gives. I run 6% UV-A in my grow room and everyone loves my homegrown. under question 2 in nevada I can now give sample to anyone over 21 who does not have a class A felony conviction

 

[MichiganMedGrower]

the first dispensary to open in northern nevada used LEDs to grow some of their plants. they also buy product from commercial growers that use CMH lights and you can taste the difference.maybe they just lack the experience since their grower is a recient graduate whose only experience was growing grapes outdoors but their LED grown house weed does not compare tho the products they buy from commercial growers and the test I ran using COBs produced the same yield (GPW) but lower taste and potency. my summer patio grows ( real sunlight) gave the best taste and potency so I'm trying to get as close to natural sunlight as I can.wish I could use CMH but I just can't handle the heat

Yup. All lighting will have a drawback. We can't fit the sun in a bulb yet. And I think you are right to point out the grow because I still think light spectrum makes the least difference. The environment and grower make the most difference.

But I have noticed the cmh quality. It is subtle and I will be persuing a better spectrum lit growroom in the future.

But I think 2 more years and we may see horticultural LED lighting explode.

 

[Morth]

I could be way off on UV-A or UV-B do know UV-B has been proven to produce more resin than not having it. Think the whole LED vs Traditional lighting is about creating the best product. Get plenty of CFL's and you can grow just probably wont be the best. I wish the scientific community was doing more testing maybe they will now that it's becoming legal for the most part. All I have to go on is research on spectrum and effect from growers that post results. I don't think any of the experiments would hold up to scientific review though. I want to be one of many microbrewery of the cannabis world not the next Budweiser. Not that there is anything wrong with Budweiser

 

[mauricem00]

Yup. All lighting will have a drawback. We can't fit the sun in a bulb yet. And I think you are right to point out the grow because I still think light spectrum makes the least difference. The environment and grower make the most difference.

But I have noticed the cmh quality. It is subtle and I will be persuing a better spectrum lit growroom in the future.

But I think 2 more years and we may see horticultural LED lighting explode.

perhaps. or a new lighting technology may be the hot new grow light. I don't know of any LED makers who are developing horticultural lights. they all seem focused on structural and area lights wonder what happened to sodium plasma lights. they use microwaves to super heat a plasma and claim to be very close to natural sunlight. it is an interesting time for growers

 

[MichiganMedGrower]

if only 1.9% UVA gave that much of and improvement I wonder what sunlight gives. I run 6% UV-A in my grow room and everyone loves my homegrown. under question 2 in nevada I can now give sample to anyone over 21 who does not have a class A felony conviction

I would grow in a light depriveable greenhouse if I could. I may make a shed into one with a clear roof so no one can see. But I have no time this year and my health is de lining unfortunately.

 

[mauricem00]

I would grow in a light depriveable greenhouse if I could. I may make a shed into one with a clear roof so no one can see. But I have no time this year and my health is de lining unfortunately.

yup!!! problem with age. we have the money, time and wisdom but not the strength . I think we all would love to be able to grow in a green house

 

[MichiganMedGrower]

yup!!! problem with age. we have the money, time and wisdom but not the strength . I think we all would love to be able to grow in a green house

I do live in the woods......

 

[Johnnycannaseed1]

Guy is long winded and I wouldn't really say it's a legit scientific experiment. On the other hand it's what we have to work with and at least he is trying.

You want UV-B not UV-A http://hightimes.com/grow/grow-hack-does-uv-light-increase-cannabis-potency/ you want it to damage the plant and for the plant to produce sunscreen/resin to protect it's self. Not sure that haveing constant UV-B bombardment during the light cycle is a great idea though but i'm less of a scientist than John Berfelo. Actually no where near that guy i'm a super noob in comparison.

Yeah I seem to remember reading somewhere that resin production could be increased with UV-B because it promoted a defence response within the plant, which in turn signalled it to produce more trichomes.

Icemud mentioned something about plants having UV receptors.... Some UV articles below for anyone who is interested.

http://thcbiomed.com/topic/uv-b-radiation-will-increase-thc-content-of-cannabis-plants/
http://onlinelibrary.wiley.com/doi/10.1111/nph.13332/pdf
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2556815/

 

[Johnnycannaseed1]

I do live in the woods......

I can imagine it must be wonderful been out there in the woods in the daytime... but come nightime don't things get a little creepy lol?

And sorry to hear about your ill health I hope it is not serious, although from your post it sounds like it might be

 

[FruitSpirit]

I have been using LED mars hydro 300w lights. I use two of them per plant. I think there actually 140w so using 2 per plant gave me 280w over 4 square foot so 70w per square foot. I have never had less than 4oz dried of very good quality product. For the price and quality i cannot fault them. I havent tried HPS though so i can only give you my LED experience. Cheap and very cheerful , they wont break the energy bills either. Running 4 lights, 2 fans, 2 extracts and a humidifier for a full cycle costs me about 45 dollars a month extra on top of the normal so the lights must be cheap to run

 

[FruitSpirit]

Oh and guys let me tell you about a time i felt really stupid, lets just say that when you use led's dont buy a lightmeter to measure the lumens....because it wont work.

P.s if anyone wants to buy a lightmeter used once for 10 seconds pm me