Light Quantity vs Light Quality Evidence ... Just for 4 u gg lol!

Do you think quantity is more important than quality


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ThaiBaby1

Well-Known Member
well just so you know pretty looking trichs aint the end all to good pot.i grow for 12 people and every one of them will pick the masterkush in the first set of pics over that frosted out wifi.and your wrong about the quality of the mk lol
Rightd! Some of the best I ever smoked had virtually NO trichs, I smoke for the high, not for the looks.
 

wietefras

Well-Known Member
I have a friend that hits 1.7~1.9 regularly with 600's in a vert garden
Oh well dont use LED then, Use that lol

Unless the veg Time is like 3 months then youre still loosing over the course of a year.

Can you link to his grow?
Well the trick there is that HPS fixtures lose a lot of light on the reflector and on the walls.

They tested the Gavita Pro fixtures and those tests indicate that already 18% of the light will be lost on the reflector.

Also, the HPS fixtures are usually designed to be placed in large green houses. They have beam angles of 140 degrees and a large distance to the canopy. In small grows this means that reflectivity of the walls becomes a very important factor, but this is also a very underrated thing in grow rooms. Mostly it's just a flat while wall with 60% diffuse reflectivity.

With a vertical HPS grow the reflector losses are eliminated and the wall losses are reduced. Therefore the yield per watt goes up since you have at least 25% more light on the plants from the same bulb. If you had a very poorly reflective grow room when using top lighting you would gain even more from going vertical.

Another thing is that the lighted surface area gets bigger. A 4 feet tall cylinder with 2 feet radius around a 600W bulb has a much larger surface area than the usual 4'x4' grow surface. The light is thus distributed over a much larger area and the resulting light intensity is probably only about 400umol/s/m2. Which will indeed produce a higher g/W ratio, but it also means the results with these types of grows tend to look fluffy. I have seen some of the vert grows going even over 2g/W (Like Heath Robinsons grow: https://www.rollitup.org/t/heaths-flooded-tube-vertical.149998/), but the harvest looked extremely "leafy" and fluffy.

For COB grows there is not real gain in yield from going vertical since there are no reflector losses (unless you insist on using them) and the wall losses are already quite low. With COBs you don't get a lighted cylinder either. The COB just lights up the same circular area but then vertical.
 

frica

Well-Known Member
Yea vertical is great for HPS but maybe actually detrimental if you're using a directional lightsource.
 

mauricem00

Well-Known Member
How is LED the one with the limited spectrum?



that is the spd for a 6500k bulb, compare the output below 440nm and at 470nm.now add a roseate or P@A bulb to fill in the red spectrum. plants will grow with any form of light but with violet and UV they produce a better quality product the LED you are showing is a 97cri diode which is less effiecient than the 80 CRI diode commonly used. T5 growers mix bulbs to get the spectrum they want. admittedly a CMH bulb provides the most useful spectrum but the LED SPD your showing does not come close to the absorption spectrum for cannabis
 

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wietefras

Well-Known Member
@mauricem00, The McCree curve is not a light recipe. It merely demonstrates how efficiently the wavelengths are used for photosynthesis (using mono colored light of that wavelength in a grow chamber).

:edit: the absorptance spectrum is even less relevant.

Plants also perform perfectly fine on just the blue en red wavelengths used for chlorophyll. Of course you will then be limited to lower light intensities since you are only using chlorophyll and leave all all the other pigments without "work".
 
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frica

Well-Known Member
that is the spd for a 6500k bulb, compare the output below 440nm and at 470nm.now add a roseate or P@A bulb to fill in the red spectrum. plants will grow with any form of light but with violet and UV they produce a better quality product the LED you are showing is a 97cri diode which is less effiecient than the 80 CRI diode commonly used. T5 growers mix bulbs to get the spectrum they want. admittedly a CMH bulb provides the most useful spectrum but the LED SPD your showing does not come close to the absorption spectrum for cannabis
The absorbance spectrum is what is just the light that doesn't get reflected.
It doesn't mean that the light is being used for photosynthesis , like with 280nm which does get absorbed but isn't used for photosynthesis.
Or that 2 spectrums with the same absorption, have the same photosynthesis efficiency.



And for the example it doesn't matter if it's a high cri or 80 cri led. A high cri has more far red. Both are just as complete.
 
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Yodaweed

Well-Known Member
That seems to be what makes people "haters" here. You have to twist said information to agree with whatever the commenter has invested in. They have spent a lot of time and money on marketing and misinformation. And your "information" is messing up their argument. :-)
Welcome to the land of magical unicorns and rainbows of LEDs , super special spectrum's and uber efficient diodes that literally defy the laws of physics. They produce 1/10th the heat even when wattages are equal (lololol) , also produce 10x more light than any other source and have the penetration of ron jeremy.
 

CoB_nUt

Well-Known Member
the ron jeremey line was rather hilarious. Dropped the cherry on my leg laughing. Ouch! These hps/cob pissing matches are entertaining. Appears the debate will last for eons. People should be able to make their own educated,informed decisions based on their own research and the knowledge from this site and others. Once you sift thru all the bs.
 

MeGaKiLlErMaN

Well-Known Member
Welcome to the land of magical unicorns and rainbows of LEDs , super special spectrum's and uber efficient diodes that literally defy the laws of physics. They produce 1/10th the heat even when wattages are equal (lololol) , also produce 10x more light than any other source and have the penetration of ron jeremy.
It's not fantasy science like Star Wars, it's legit to be fair. There is less heat., by how much in a real world situation? That I'm not sure until Ihave 3000W of cobs, we will see when the time comes for more lights.its closer to 1/3 the heat though. And the lumens per watt are around 190-200 if you go hard on efficientcy so I mean they do out out a lot more than HPS while giving a better spectrum
 

frica

Well-Known Member
DE 1000 watt HPS should still be among the top recommendations when it comes to anything above 16 square foot.
The efficiency + price still make it a great option.
Same goes for CMH if it's a reasonably priced kit.

Fluorescent on the other hand not so much.
 

Yodaweed

Well-Known Member
It's not fantasy science like Star Wars, it's legit to be fair. There is less heat., by how much in a real world situation? That I'm not sure until Ihave 3000W of cobs, we will see when the time comes for more lights.its closer to 1/3 the heat though. And the lumens per watt are around 190-200 if you go hard on efficientcy so I mean they do out out a lot more than HPS while giving a better spectrum
That defies the laws of physics , mainly the first law of thermodynamics, 1000w of any source will nearly = 1000w of another in an enclosed system google first law of thermodynamics and read it. Light is radiant energy , which transfers to heat. All watts were created equally :)

http://www.rapidtables.com/convert/power/Watt_to_BTU.htm

For quick conversions to estimate how many BTU of Air Condition you will need.
 

MichiganMedGrower

Well-Known Member
That defies the laws of physics , mainly the first law of thermodynamics, 1000w of any source will nearly = 1000w of another in an enclosed system google first law of thermodynamics and read it. Light is radiant energy , which transfers to heat. All watts were created equally :)

http://www.rapidtables.com/convert/power/Watt_to_BTU.htm

For quick conversions to estimate how many BTU of Air Condition you will need.
I am pretty sure that the type of lighting changes this fact. You are talking about ignited gasses in a tube rather than a circuit only. They can produce different light to heat ratios.

Even HPS and MH have different heat to light amounts.
 

Yodaweed

Well-Known Member
I am pretty sure that the type of lighting changes this fact. You are talking about ignited gasses in a tube rather than a circuit only. They can produce different light to heat ratios.

Even HPS and MH have different heat to light amounts.
yeah but it's not a huge factor, 1000w of hps will be just about as much heat as 1000w of mh lights,same with 1000w of leds, main difference will be leaf temps due to ir (which heats surface but won't create more watts or heat in the whole system) , if you don't believe me enclose a 1000w hps in an area, take temp measurements then enclose a 1000w metal halide, should be very close temp wise.
 
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