sorry typo 2000Typically a 1000w hps se has about 1700umol at source, 4000 is not right, maybe youre thinking of ppfd and not ppf?
sorry typo 2000Typically a 1000w hps se has about 1700umol at source, 4000 is not right, maybe youre thinking of ppfd and not ppf?
just your typo...What's nope about?
The best way to know if their numbers are solid or not is to see if they testing in a integrating sphere. It's the best way most appropriate way to isolate the light form the unit and drive to an accurate result. Gavita uses integrating spheres for testing. A company like Spider Farmer openly admits to testing in tents. In tents you can get additional boost from refractory properties of the walls and light pollution. Another way is to look at their advertised numbers and their DLC results if they are certified. I've noticed a few companies advertised results can be different from their DLC stated specifications.It takes 394w of LED using the best Samsung Diodes, and also possible use of Osram Red/Far Red to equal the best 600w HPS bulb. Ill use the Hortilux 600w HPS as an example
Heres how I get my logic.
Consider Gavita says their 645w 1700e is a direct replacement in a 4 x 4 area, for a 1000w HID. Ill use the Hortilux 1000w HPS as an example
The Gavita puts out 1781umol,, its conservatively rated at 1700umol
The 1000w Hortilux HPS is roughly 1880umol. Also consider the first month an HID loses 10% output, and then stabilizes. So that would make the HPS 1692umol.
At 645w for a 16 sq/ft area, that means the Gavita is 40.3w sq/ft. The 1000w Hortilux is 62.5w sq/ft.
So at that rate, an LED is roughly 35.8% more efficient than a 1000w Hortilux.
35.8% of 600w is 394w to equal a 600w HPS using the best bulb. Also assuming one is using the best Diodes available. If not all bets are off.
At that rate it will take about 3 of those 125w LED youre using to equal a 600w Hortilux. IF it has Sumsung Diodes.
One thing I like about Gavita, is they dont overrate their product. They say their 1700e covers a 4 x 4 area in flowering. So I believe them, especially considering I see other manufacturers claiming a 5 x 5 area, and their LED have the same, or close to the same umol, and wattage as the Gavita.
Red/Far Red has also been all but proven to make bigger plants, and a higher yield.
Israel did a test 30 years or more ago about using red infused coloring in the glass, or whatever material they use for their greenhouses.
The grew the exact same flowers from Tissue Culture, and in one greenhouse, they used red infused glass, or whatever material the used. And the other greenhouse they just used clear/normal uncolored. The Red infused greenhouse plants were twice as big as the flowers in the untreated greenhouse.
Also consider Israel is one of the top countries in the world to use greenhouses to grow produce, and have been for decades.
LOLjust your typo...![]()
your right there cowboy!!! were in the wild west alright and ive got myself an ithcy trigger finger!...We're still in the wild wild west of fully understanding spectral cultivation.
The study done in Israel was on PBS TV more than 20-25 years ago. Early 90s.The best way to know if their numbers are solid or not is to see if they testing in a integrating sphere. It's the best way most appropriate way to isolate the light form the unit and drive to an accurate result. Gavita uses integrating spheres for testing. A company like Spider Farmer openly admits to testing in tents. In tents you can get additional boost from refractory properties of the walls and light pollution. Another way is to look at their advertised numbers and their DLC results if they are certified. I've noticed a few companies advertised results can be different from their DLC stated specifications.
Do you have a citation for those testing studies done in Israel?
There have been some decent studies in recent years that are supporting the use of different spectra.
Magagnini shows a comparison between HPS and LED https://www.karger.com/Article/Fulltext/489030#ref22
The Jenkins has data on UV https://www.scirp.org/journal/paperinformation.aspx?paperid=113836
![]()
(PDF) Influence of Light Spectra on the Production of Cannabinoids
PDF | In recent years, more attention has been paid to cannabis from both medical and political points of view. This study investigates the influence of... | Find, read and cite all the research you need on ResearchGatewww.researchgate.net
The Amrein really breaks down spectra and show direct correlation to yield
![]()
(PDF) Influence of Light Spectra on the Production of Cannabinoids
PDF | In recent years, more attention has been paid to cannabis from both medical and political points of view. This study investigates the influence of... | Find, read and cite all the research you need on ResearchGatewww.researchgate.net
While this is great research its just the tip of the iceburg, there needs to be more research conducted. Forums like this are appreciated but different geno and chemotypes of plants can also produce difference results. We're still in the wild wild west of fully understanding spectral cultivation.
Hi jimi I have been looking at that gavita would you say that its a decent light?It takes 394w of LED using the best Samsung Diodes, and also possible use of Osram Red/Far Red to equal the best 600w HPS bulb. Ill use the Hortilux 600w HPS as an example
Heres how I get my logic.
Consider Gavita says their 645w 1700e is a direct replacement in a 4 x 4 area, for a 1000w HID. Ill use the Hortilux 1000w HPS as an example
The Gavita puts out 1781umol,, its conservatively rated at 1700umol
The 1000w Hortilux HPS is roughly 1880umol. Also consider the first month an HID loses 10% output, and then stabilizes. So that would make the HPS 1692umol.
At 645w for a 16 sq/ft area, that means the Gavita is 40.3w sq/ft. The 1000w Hortilux is 62.5w sq/ft.
So at that rate, an LED is roughly 35.8% more efficient than a 1000w Hortilux.
35.8% of 600w is 394w to equal a 600w HPS using the best bulb. Also assuming one is using the best Diodes available. If not all bets are off.
At that rate it will take about 3 of those 125w LED youre using to equal a 600w Hortilux. IF it has Sumsung Diodes.
One thing I like about Gavita, is they dont overrate their product. They say their 1700e covers a 4 x 4 area in flowering. So I believe them, especially considering I see other manufacturers claiming a 5 x 5 area, and their LED have the same, or close to the same umol, and wattage as the Gavita.
Red/Far Red has also been all but proven to make bigger plants, and a higher yield.
Israel did a test 30 years or more ago about using red infused coloring in the glass, or whatever material they use for their greenhouses.
The grew the exact same flowers from Tissue Culture, and in one greenhouse, they used red infused glass, or whatever material the used. And the other greenhouse they just used clear/normal uncolored. The Red infused greenhouse plants were twice as big as the flowers in the untreated greenhouse.
Also consider Israel is one of the top countries in the world to use greenhouses to grow produce, and have been for decades.
it was 2 years ago...Hi jimi I have been looking at that gavita would you say that its a decent light?
![]()
Gavita Pro 1700e LED Grow Light 645w
Please note these are purchase to order and land with us within 1-2 working days Runs at 2.6 µmol per watt - get more light for the same power useage! By comparison, the very best professional HPS grow lights produce only 2.1 µmols per watt and most produce a lot less (down to as little as 1.8...www.onestopgrowshop.co.uk
What was 2 years ago?it was 2 years ago...
lol fake SANlight influencer non-senseMagagnini shows a comparison between HPS and LED https://www.karger.com/Article/Fulltext/489030#ref22
I could care less about the lights used. I was only showing examples of what research papers are out there. We need more research with more lights and strainslol fake SANlight influencer non-sense
edit:
but thx anyway for posting this
it's not about the lights per se but the work is full of methodological errorsI could care less about the lights used. I was only showing examples of what research papers are out there. We need more research with more lights and strains
You can tell these are academics doing this work and not growers, that or they have an agenda but atleast the work is transparent so you can poke those holes in it. What we need moving forward is growers and industry experts working on these papers with academia.it's not about the lights per se but the work is full of methodological errors
which casts a huge shadow of doubt on the legitimacy of the results
they are claiming to flower out cannabis at "optimal conditions" but target 500 umol ppfd for flower
they veg under 400W MH 18/6 but flower under 275W HPS at 12/12 [!!!] even dimming
measuring ppfd at different heights (the LEDs in greater distance to arrive at the same numbers lol!)
alot of data is missing, esp. for the LED, not even the plants are shown, for the flower tent they duplicate all the veg pics
basically light-starving all plants, no wonder an almost monochromatic mostly 660nm spec fared best...
the light was a good light two years ago... not so much today.What was 2 years ago?
believe me I have sighted hundreds after hundreds of legit studies but this isnt one. not really transparent and full of flaws. their conclusion is that the "plurple spec" is best...You can tell these are academics doing this work and not growers, that or they have an agenda but atleast the work is transparent so you can poke those holes in it. What we need moving forward is growers and industry experts working on these papers with academia.
During the first run of the experiment, several prob-lems were encountered.
For instance, the water supply via the dosing units was not sufficient, resulting in different fertilizer mixtures in different boxes. This problem could be solved in the last 4 weeks of flowering.
Apart from that, due to a malfunction of the dosing unit, plants in box 7 were fertilized with undiluted fertilizer. This had a negative impact on the plants, and they were replaced by oth-er plants which nonetheless still showed a rather high content of CBDA.
im not saying its bad just for that price today you can get cheaper and more efficient...The Gavita is a great light, and compares to any light with the same wattage made today. The 1700e has 3300 diodes. 1781umol. Also has a 5 Year warranty.
Gavita also makes the 1930e, which is 1930umol, and is supposed to replace a DE HPS. Its 780w. It will cover a 5 x 5 area.
I'm sorry the first is really esoteric, and both theories or write-ups still make the old error in thinking that chlorophylls can't absorb green photons. they can - and do.@Kassiopeija i seen these posted on another forum and thought you might find them interesting,
https://www.quantamagazine.org/why-are-plants-green-to-reduce-the-noise-in-photosynthesis-20200730/
http://www.esalq.usp.br/lepse/imgs/conteudo_thumb/Why-did-chlorophyl-evolve-to-be-green-as-opposed-to-black.pdf
im not saying its bad just for that price today you can get cheaper and more efficient...