Have any of you DIY COB Growers finished a crop under 1000W DE HPS? - POLL

Have any of you DIY COB Growers have actually finished a crop under 1000W DE HPS?

  • Yes

    Votes: 32 29.1%

  • No

    Votes: 78 70.9%
  • Total voters
    110
Olive Drab Green

Olive Drab Green

Well-Known Member
Yodaweed said:
Very intense in a very small area , which leads to lack of intensity in numerous spots, its like shining a flashlight on your plants some areas will get a beam of light others will be in the dark. Guess you guys don't understand how LEDs work yet, they are best without the reflectors and low to a canopy that's really tight like on a scrog.
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I don't think it would be a good idea to have them too low. Honestly, I suspect it would cause photoinhibition. Mine are currently about 18" from the. canopy and growing great. As mentioned yesterday, covered in capitate-sessile trichomes while still in mid-veg. I suspect that means they are "happy."
 
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Yodaweed

Yodaweed

Well-Known Member
KarmaPaymentPlan said:
lol prove it
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Don't need to , it was already proven for me years ago

Inverse-square law
In physics, an inverse-square law is any physical law stating that a specified physical quantity or intensity is inversely proportional to the square of the distance from the source of that physical quantity.

A law cannot be disproven by the way...


https://en.wikipedia.org/wiki/Inverse-square_law

Read up you got a lot to learn.
 
KarmaPaymentPlan

KarmaPaymentPlan

Well-Known Member
this is the same shit everyone always argues about the sad fact is we have thousands of satisfied cob growers and they dont give a shit about math or inverse laws the results speak for themselfs
 
Yodaweed

Yodaweed

Well-Known Member
KarmaPaymentPlan said:
but when the 100w cob is more intense then 1/10th of an hps how do you do the math now?
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You didn't read my comment, I said 100w of cob vs 1000w of cob, never said hps, but 1000w of hps is more intense than 100w cob anyday of the week, just too much output to even come close, probably not 10x more but i'd imagine at least 5x more.
 
KarmaPaymentPlan

KarmaPaymentPlan

Well-Known Member
Yodaweed said:
You didn't read my comment, I said 100w of cob vs 1000w of cob, never said hps, but 1000w of hps is more intense than 100w cob anyday of the week, just too much output to even come close, probably not 10x more but i'd imagine at least 5x more.
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now your mixing things up get your story straight
 
Yodaweed

Yodaweed

Well-Known Member
KarmaPaymentPlan said:
this is the same shit everyone always argues about the sad fact is we have thousands of satisfied cob growers and they dont give a shit about math or inverse laws the results speak for themselfs
Click to expand...
:dunce::dunce::dunce::dunce::dunce::dunce::dunce::dunce::dunce:DERRRPPPP MATH IS HARD FER MEH:dunce::dunce::dunce::dunce::dunce::dunce::dunce::dunce:I DONT UNDERSTAND SO I DONT CARE DERRRPPPP:dunce::dunce::dunce::dunce::dunce::dunce::dunce::dunce::dunce::dunce::wall::wall::wall::wall::wall:
 
Olive Drab Green

Olive Drab Green

Well-Known Member
Yodaweed said:
You didn't read my comment, I said 100w of cob vs 1000w of cob, never said hps, but 1000w of hps is more intense than 100w cob anyday of the week, just too much output to even come close, probably not 10x more but i'd imagine at least 5x more.
Click to expand...
So what is the PPFD at proper height for both a 600w and 1000w HPS?
 
KarmaPaymentPlan

KarmaPaymentPlan

Well-Known Member
Yodaweed said:
That means you are really lowering their coverage and PAR ratings, reflectors kill LEDs, they absorb light and also have losses , much higher losses than HID ones, they are basically some of the newest tech on the market and definitely have a LONNGGGG ways to go before they are working as intended. I believe someone on this very forum measured PAR with and without reflectors and saw a dramatic drop off with the reflectors. They also will cause extreme hot spots.
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remember this!!!!

keep your story straight and think before you talk
 
Yodaweed

Yodaweed

Well-Known Member
KarmaPaymentPlan said:
a cobs a cob what happened to hanging more of them DEEEEERRREPPPPPPP
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More doesn't increase intensity it just spreads it out, man you don't learn and can't keep your foot out of your mouth. Sad that's what the world has come to, dumb ass ignorant people that don't want to learn or listen, by the way I have my bachelors in engineering and taught calculus as a TA for a year.
 
KarmaPaymentPlan

KarmaPaymentPlan

Well-Known Member
Yodaweed said:
More doesn't increase intensity it just spreads it out, man you don't learn and can't keep your foot out of your mouth. Sad that's what the world has come to, dumb ass ignorant people that don't want to learn or listen, by the way I have my bachelors in engineering and taught calculus as a TA for a year.
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so if you hang 10 100w cobs all next to each other your saying a cob with 1000w from the same area would penetrate more?
 
bassman999

bassman999

Well-Known Member
Yodaweed said:
Very intense in a very small area , which leads to lack of intensity in numerous spots, its like shining a flashlight on your plants some areas will get a beam of light others will be in the dark. Guess you guys don't understand how LEDs work yet, they are best without the reflectors and low to a canopy that's really tight like on a scrog.
Click to expand...
That is how mine are running.
I have 12 in a 2x4 area @12" above scrogged canopy.

My reasoning was low 5' tent height though
 
Yodaweed

Yodaweed

Well-Known Member
KarmaPaymentPlan said:
so if you hang 10 100w cobs all next to each other your saying a cob with 1000w from the same area would penetrate more?
Click to expand...
Dude read the fucking law I posted you, it states why the initial value is the most important thing.

Inverse-square law
In physics, an inverse-square law is any physical law stating that a specified physical quantity or intensity is inversely proportional to the square of the distance from the source of that physical quantity.



Light and other electromagnetic radiation[edit]
The intensity (or illuminance or irradiance) of light or other linear waves radiating from a point source (energy per unit of area perpendicular to the source) is inversely proportional to the square of the distance from the source; so an object (of the same size) twice as far away, receives only one-quarter the energy (in the same time period).

More generally, the irradiance, i.e., the intensity (or power per unit area in the direction of propagation), of a spherical wavefront varies inversely with the square of the distance from the source (assuming there are no losses caused by absorption or scattering).

For example, the intensity of radiation from the Sun is 9126 watts per square meter at the distance of Mercury (0.387 AU); but only 1367 watts per square meter at the distance of Earth (1 AU)—an approximate threefold increase in distance results in an approximate ninefold decrease in intensity of radiation.

For non-isotropic radiators such as parabolic antennas, headlights, and lasers, the effective origin is located far behind the beam aperture. If you are close to the origin, you don't have to go far to double the radius, so the signal drops quickly. When you are far from the origin and still have a strong signal, like with a laser, you have to travel very far to double the radius and reduce the signal. This means you have a stronger signal or have antenna gain in the direction of the narrow beam relative to a wide beam in all directions of an isotropic antenna.

In photography and stage lighting, the inverse-square law is used to determine the "fall off" or the difference in illumination on a subject as it moves closer to or further from the light source. For quick approximations, it is enough to remember that doubling the distance reduces illumination to one quarter;[8] or similarly, to halve the illumination increase the distance by a factor of 1.4 (the square root of 2), and to double illumination, reduce the distance to 0.7 (square root of 1/2). When the illuminant is not a point source, the inverse square rule is often still a useful approximation; when the size of the light source is less than one-fifth of the distance to the subject, the calculation error is less than 1%.[9]

The fractional reduction in electromagnetic fluence (Φ) for indirectly ionizing radiation with increasing distance from a point source can be calculated using the inverse-square law. Since emissions from a point source have radial directions, they intercept at a perpendicular incidence. The area of such a shell is 4πr 2 where r is the radial distance from the center. The law is particularly important in diagnostic radiography and radiotherapy treatment planning, though this proportionality does not hold in practical situations unless source dimensions are much smaller than the distance. As stated in fourier theory of heat "as the point source is magnification by distances , its radiation is dilute proportional to the sin of the angle, of the increasing circumference arc from the point of origin"
 
KarmaPaymentPlan

KarmaPaymentPlan

Well-Known Member
bassman999 said:
That is how mine are running.
I have 12 in a 2x4 area @12" above scrogged canopy.

My reasoning was low 5' tent height though
Click to expand...
the idea of having over lap on a small scale grow just doesnt make sense to him
sure 1000w fixtures hung next to eachother in a large opertaion helps spread light but according to yoda you cant get the same benefit with lower wattage emitters
 
KarmaPaymentPlan

KarmaPaymentPlan

Well-Known Member
Yodaweed said:
Dude read the fucking law I posted you, it states why the initial value is the most important thing.

Inverse-square law
In physics, an inverse-square law is any physical law stating that a specified physical quantity or intensity is inversely proportional to the square of the distance from the source of that physical quantity.



Light and other electromagnetic radiation[edit]
The intensity (or illuminance or irradiance) of light or other linear waves radiating from a point source (energy per unit of area perpendicular to the source) is inversely proportional to the square of the distance from the source; so an object (of the same size) twice as far away, receives only one-quarter the energy (in the same time period).

More generally, the irradiance, i.e., the intensity (or power per unit area in the direction of propagation), of a spherical wavefront varies inversely with the square of the distance from the source (assuming there are no losses caused by absorption or scattering).

For example, the intensity of radiation from the Sun is 9126 watts per square meter at the distance of Mercury (0.387 AU); but only 1367 watts per square meter at the distance of Earth (1 AU)—an approximate threefold increase in distance results in an approximate ninefold decrease in intensity of radiation.

For non-isotropic radiators such as parabolic antennas, headlights, and lasers, the effective origin is located far behind the beam aperture. If you are close to the origin, you don't have to go far to double the radius, so the signal drops quickly. When you are far from the origin and still have a strong signal, like with a laser, you have to travel very far to double the radius and reduce the signal. This means you have a stronger signal or have antenna gain in the direction of the narrow beam relative to a wide beam in all directions of an isotropic antenna.

In photography and stage lighting, the inverse-square law is used to determine the "fall off" or the difference in illumination on a subject as it moves closer to or further from the light source. For quick approximations, it is enough to remember that doubling the distance reduces illumination to one quarter;[8] or similarly, to halve the illumination increase the distance by a factor of 1.4 (the square root of 2), and to double illumination, reduce the distance to 0.7 (square root of 1/2). When the illuminant is not a point source, the inverse square rule is often still a useful approximation; when the size of the light source is less than one-fifth of the distance to the subject, the calculation error is less than 1%.[9]

The fractional reduction in electromagnetic fluence (Φ) for indirectly ionizing radiation with increasing distance from a point source can be calculated using the inverse-square law. Since emissions from a point source have radial directions, they intercept at a perpendicular incidence. The area of such a shell is 4πr 2 where r is the radial distance from the center. The law is particularly important in diagnostic radiography and radiotherapy treatment planning, though this proportionality does not hold in practical situations unless source dimensions are much smaller than the distance. As stated in fourier theory of heat "as the point source is magnification by distances , its radiation is dilute proportional to the sin of the angle, of the increasing circumference arc from the point of origin"
Click to expand...
i wasn't aware that light does not blend i guess saturation levels mean nothing

so if you hang 10 100w cobs all next to each other your saying a cob with 1000w from the same area would penetrate more? please answer my question
 
Yodaweed

Yodaweed

Well-Known Member
KarmaPaymentPlan said:
the idea of having over lap on a small scale grow just doesnt make sense to him
sure 1000w fixtures hung next to eachother in a large opertaion helps spread light but according to yoda you cant get the same benefit with lower wattage emitters
Click to expand...
You have to hang them lower, its not according to me, its according to the laws of physics. I think I am done here, I really can't go any deeper into detail, I guess this one just too complicated for you to understand.
 
OLD MOTHER SATIVA

OLD MOTHER SATIVA

Well-Known Member
yoda makes sense....many little cobs will do better even coverage..one 1000w cob with reflector would have big time penetration but would have to be raised to cover much area
 
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