Of course it won't be because there are diminishing returns to light intensity, irrespective of whether the inverse square law applies.
Pine
Inverse-Square 'LAW' of Light
- Thread starter smokinshogun
- Start date
Of course it won't be because there are diminishing returns to light intensity, irrespective of whether the inverse square law applies.
Pine
This paragraph right here explains full well that you don't understand the subject.
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T.J
How do you think scientists work? Do they reinvent the wheel for every new car model?
NO, they read and understand things that are proven by someone else.
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TheMintMan
And how do you think incorrect theories are disproven? Usually, some past "scientist" is proven wrong. Believe it or not, way back when there were actually SCIENTISTS who thought the world was flat. What if we all just believed what every scientist said? Our heads would explode because often times scientists are working on opposing theories...to get funding, they present their theories as fact.
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T.J
But you can't argue with modern day physics, that is rock solid. As long as you don't go down on a sub-atomic level.
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T.J
COME ON .. LOOK AROUND YOU !!
The modern society wouldn't exist if there were sooooooo basic flaws in the physics area.
Learn some math and geometry and look at that article again. Nuff said.
The modern society wouldn't exist if there were sooooooo basic flaws in the physics area.
Learn some math and geometry and look at that article again. Nuff said.
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TheMintMan
Yeah, they said the same thing back then too...lol.
And I know plenty of math, thanks. Not interested in the article. I do not have time to click on every link that someone throws up and investigate it's legitimacy. All I'm saying is that it's just silly to use someone's job title as an argument.
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T.J
Yeah and when was this?
The "modern society" of the middle ages? ..
I'm for one am convinced that a cab isn't a sphere. And only because of that the law doesn't apply to our situation.
The "modern society" of the middle ages? ..
I'm for one am convinced that a cab isn't a sphere. And only because of that the law doesn't apply to our situation.
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TheMintMan
What they called science back then was science. We scoff at it. What we call science, 100 years from now, may be just as laughable.
Yes I have. :smile:
I understand it, thank you. Old news.
Back then the world was FLAT, they had never left the planet and didn't really live with 'science' all around them to prove why it couldnt be. It really had no impact on their daily life either way, round or flat. The world is flat, have you ever ACTUALLY SEEN anything to prove its not actually 'flat'. You could go around half the planet and not even know you were on the other side.... ITS FLAT!. You can argue ANYTHING...
Yes I have. :smile:
smokingshogun said:
I understand it, thank you. Old news.
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TheMintMan
But what if you do have 4 times the surface area?
Some have cabinets...others have rooms that are way too big for the light they have, until they get a replacement for the one that blew.
In my situation, the 1/4 intensity is accurate. My room is too big for my light right now and my walls are nowhere near my plant. So for the moment, I've got to move her up, or the light down.
Listen to the plants...be a plant whisperer...and you'll do much better with a grow than any scientist I've met.
Some have cabinets...others have rooms that are way too big for the light they have, until they get a replacement for the one that blew.
In my situation, the 1/4 intensity is accurate. My room is too big for my light right now and my walls are nowhere near my plant. So for the moment, I've got to move her up, or the light down.
Listen to the plants...be a plant whisperer
...and you'll do much better with a grow than any scientist I've met.
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TheMintMan
I don't think you understand my setup...nor what I am trying to say.
Good luck with your arguing. I've got some plants to tend to.
Good luck with your arguing. I've got some plants to tend to.
Holly fuck that was a long read, but very interesting and really got me thinking.
I totally understand where smokinshogun is coming from.
I have in fact just starting having my lights further away from the canopy due to advice from a friend that has sick results, not because of the inverse square law or anything do do with this thread, but this thread got me to thinking that its the right thing to do.
Im just increasing the area of plants getting x amount of lumens instead of a small number getting lots more and lots being in the shade and getting far less, because i thought that moving the light further away decreased the lumens due to how far the light had to travel, but its the area they cover causing less lumens therefore i will just have almost the same lumens not accounting for loss's in reflection etc, just spread over more plants so a more even canopy but over all the same lumens.
Garh i explained that very badly but i get the point smokin is making and i agree.
I dont have a small cab with a light that fits etc but i do see what smokin is saying, no one is saying the inverse square law is wrong just that it isnt the be all and end all in the case of a grow room.
Let the flameing begin...
Row
I totally understand where smokinshogun is coming from.
I have in fact just starting having my lights further away from the canopy due to advice from a friend that has sick results, not because of the inverse square law or anything do do with this thread, but this thread got me to thinking that its the right thing to do.
Im just increasing the area of plants getting x amount of lumens instead of a small number getting lots more and lots being in the shade and getting far less, because i thought that moving the light further away decreased the lumens due to how far the light had to travel, but its the area they cover causing less lumens therefore i will just have almost the same lumens not accounting for loss's in reflection etc, just spread over more plants so a more even canopy but over all the same lumens.
Garh i explained that very badly but i get the point smokin is making and i agree.
I dont have a small cab with a light that fits etc but i do see what smokin is saying, no one is saying the inverse square law is wrong just that it isnt the be all and end all in the case of a grow room.
Let the flameing begin...
Row
Philosophelon
Member
So basically...
The fact that a bulb when installed in a horizontal reflector is not an isotropic source of radiant energy, and that the inverse square law does not account for reflection, absorption, and scattering, means that the inverse square law is not the most accurate way to calculate the decrease in irradiance due to bulb height.
That is probably true.
So then what is a convenient alternative to the inverse square law to use when calculating the decrease in irradiance due to bulb height?
If it's a huge PITA, everyone (myself included) will just stick with the ISL, which still works for the hot-spot, because that light does cover exponentially more surface area and is not reflected.
The fact that a bulb when installed in a horizontal reflector is not an isotropic source of radiant energy, and that the inverse square law does not account for reflection, absorption, and scattering, means that the inverse square law is not the most accurate way to calculate the decrease in irradiance due to bulb height.
That is probably true.
So then what is a convenient alternative to the inverse square law to use when calculating the decrease in irradiance due to bulb height?
If it's a huge PITA, everyone (myself included) will just stick with the ISL, which still works for the hot-spot, because that light does cover exponentially more surface area and is not reflected.
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NOYB
I used those charts by Cali Grower fro reference a lot when peeps would ask about lighting stuff. I chatted with him fairly extensively a few years ago on the CC forums and the guy knew his stuff. Learned a lot from him about growing in general. Definitely one of my early mentors.
Only just spotted this thread but me and smoking were talking about this previously on another thread.
He is totaly right and the inverse square law is a load of shit in this case. Dont get me wrong its derived from real physics but applied to the wrong situation. If you think I'm wrong you MUST explain the following. Ever seen a performer on a dark stage illuminated by a spot light 50m away or more? - where is the inverse square law? PLEASE, im interested to know. It uses a parabolic reflector to send out light in one straight direction. ONly if you've got a bulb with no reflective walls, with no reflector - the light will go in all directions and the rule applies. ONLY then.
Now imagine the simplest possible reflector which is just a ceiling right above the bulb (No walls!). Imagine that the top semi-sphere of light from the above scenaria is now reflected down. You now have halved the total Area of the light sphere. Assuming Perfect reflection (no absorption from the ceiling) you have have halved area so the semisphere below bulb now has double the light. Therefore you now have a inverse linear relationship (double distance/ half light) - not and inverse square relationship( double distance/ quarter light). This is with a very simple model - reality would be different but we have better reflectors than just a ceiling!
He is totaly right and the inverse square law is a load of shit in this case. Dont get me wrong its derived from real physics but applied to the wrong situation. If you think I'm wrong you MUST explain the following. Ever seen a performer on a dark stage illuminated by a spot light 50m away or more? - where is the inverse square law? PLEASE, im interested to know. It uses a parabolic reflector to send out light in one straight direction. ONly if you've got a bulb with no reflective walls, with no reflector - the light will go in all directions and the rule applies. ONLY then.
Now imagine the simplest possible reflector which is just a ceiling right above the bulb (No walls!). Imagine that the top semi-sphere of light from the above scenaria is now reflected down. You now have halved the total Area of the light sphere. Assuming Perfect reflection (no absorption from the ceiling) you have have halved area so the semisphere below bulb now has double the light. Therefore you now have a inverse linear relationship (double distance/ half light) - not and inverse square relationship( double distance/ quarter light). This is with a very simple model - reality would be different but we have better reflectors than just a ceiling!
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NOYB
What's the intensity of the light at the source compared to where it's being focused on? I'm talking about actual meter readings so I can understand better.
Rectangular prisms? A new one on me.
Rectangular prisms? A new one on me.
Its simple pyhsics, REAL SIMPLE...
"Also please take your pictures from farther away so that we can see where the tape measure ACTUALLY begins at, otherwise its pretty useless for us and doesn't provide a reference point..
As you wish sir.
Thanks for the prism link. I learned something.
"Thanks for stopping by, not reading anything, and cherry-picking a quote to make me sound like an idiot.
The point of me saying that was to show that I don't need to even know what those words mean to know I'm right.
Would you care to give your 'version' of the inverse-square law and please explain to me how the distance from the actual source causes a decrease of light? Try getting around 1/4 the intensity, without 4 times the surface area...The density WILL NOT decrease to 25% when they don't have 4 times the space to spread out to. That what the law says to me."
Well sir, I have read both threads in toto, and everything in your album.
Jus' tryin' to find what closed your mind.
You started a far red thread and seemed intelligent and articulate. I was thrilled.
Now you take an untenable position and defend it to the death. WTF.
Do you really believe that walls have any effect on the "spread"? Or, do you just like to
?
Gotta give ya points for holding your ground, I guess.
Hey M. C.
You, I like!
Silly looking avatar hiding a very good mind.
Something quite "round" about that.
Enjoyed reading your cogent replies to
Don't realy care what SS "believes".
There's usually a wide gap 'tween faith and fact!
Just don't want to lose his far red input to the forums just 'cause he's dug himself into a hole.
But, I've put in enough effort.
I'm off to fish for information among the factual.
Play nice.
Weezard
Rectangular prisms? A new one on me.
Its simple pyhsics, REAL SIMPLE...
"Also please take your pictures from farther away so that we can see where the tape measure ACTUALLY begins at, otherwise its pretty useless for us and doesn't provide a reference point..
As you wish sir.
Thanks for the prism link. I learned something.
"Thanks for stopping by, not reading anything, and cherry-picking a quote to make me sound like an idiot.
The point of me saying that was to show that I don't need to even know what those words mean to know I'm right.
Would you care to give your 'version' of the inverse-square law and please explain to me how the distance from the actual source causes a decrease of light? Try getting around 1/4 the intensity, without 4 times the surface area...The density WILL NOT decrease to 25% when they don't have 4 times the space to spread out to. That what the law says to me."
Well sir, I have read both threads in toto, and everything in your album.
Jus' tryin' to find what closed your mind.
You started a far red thread and seemed intelligent and articulate. I was thrilled.
Now you take an untenable position and defend it to the death. WTF.
Do you really believe that walls have any effect on the "spread"? Or, do you just like to
?Gotta give ya points for holding your ground, I guess.
Hey M. C.
You, I like!
Silly looking avatar hiding a very good mind.
Something quite "round" about that.
Enjoyed reading your cogent replies to
Don't realy care what SS "believes".
There's usually a wide gap 'tween faith and fact!
Just don't want to lose his far red input to the forums just 'cause he's dug himself into a hole.
But, I've put in enough effort.
I'm off to fish for information among the factual.
Play nice.
Weezard
That's actually a myth. At no point in history have poeple believed that the world was flat. Its repeated time and time again, but it isnt so.
