How high to hang LED light

This light is driving me nuts,lol.
You've taken in a lot of info about grow lighting and you're using it to your advantage. That's learning which is creating knowledge that will serve you well. There's a few other areas of knowledge that fit together to make up the grow environment. Once you get that down, things make more sense. Big picture - they're all connected which makes sense because we're creating and controlling an environment for another lifeforms.

Give it time. I've been at this for two years now and I keep coming up with better questions. :)

I raised to 16 inches then turned up the dimmer to get that reading.
You're good. Done for the day.

The whole plant was not going down,just a couple.
Good. That's what it looked like. Doin' fine.


This grow is Dwc,75 degrees,48 percent rh
OK, wanna talk about "vapor pressure deficit"?

OP runs away, screaming.
OP deletes thread
OP takes up tropical fish.
 
i run everything 18 to 24 inches. in veg i start at 18, as the plants hit the 24 inch mark i raise it. in flower i leave it at 18 after stretch. i use a combination of dimming and height.
 
I don't think that anyone here can tell you exactly how far to put your lights.
Because the question is not how far should your light be, but how many LUX's, PAR's etc. are your plants getting.
Bruce Bugby has very good video on that.
He shows exactly why you HAVE to use a light meter if you don't want to have issues.
My advise is buy a cheap light meter and monitor your plants, because as they grow, the values are growing too.
 
i don't know a singe grower using a par meter. only guys here lol

You don't need a par meter.
They are too expensive.
This is a random one that I found on amazon it's ilke 30bucks.
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It's not a PAR meter, it shows LUX and FC.
If you learn (or read) the values in LUX or FC, you can do just fine.
I know someone will say that PAR and LUX will not be exactly the same number when they converted.
But this way works just fine.
 
Me either. Even the big ones I have been behind the scenes at. Only here. But I have one, but like I said never sees the light of day. BwhahahahahahHa

Well some people use it.
When your setup is already dialed in you don't need it.
But when you are new and don't know a thing about that, or if you are setting up a new room with new lights...
It's better to check.
 
Well some people use it.
When your setup is already dialed in you don't need it.
But when you are new and don't know a thing about that, or if you are setting up a new room with new lights...
It's better to check.
Yes it is better to check. But if you use lux do the conversion to par ie. multiply the LUX readout by 0.017 for the PAR. Otherwise I really see no need.
 
Me either. Even the big ones I have been behind the scenes at. Only here. But I have one, but like I said never sees the light of day.


haven't seen them in commercial grows either. i do know that they do a calculation when choosing lights, and most are fixed, they don't move. they move the plants from room to room.



edit : seemed mean.
 
haven't seen them in commercial grows either. i do know that they do a calculation when choosing lights, and most are fixed, they don't move. they move the plants from room to room.




edit : seemed mean.

In the big commercial grows the hanging of the lights is done by a company.
Everything is calculated and measured prior to the hanging of the lights.
If you want to do it on your own, you will need a meter or two.
Even they use meters, before they hand the keys to the grower.
It's like with the irrigation system, the company installs all the pumps and hoses and tanks.
But if you want to do it on your own you will have to read a thing or two about GPH, Pump pressure and things like that.
All I'm saying is that if you want to do it right do it right, because I've had a lot of issues with lights.
And whatever people were telling me was not correct.
And I bet you know how long it takes for a plant to recover from a light/heat stress...
So that's when I decided that a meter would be a handy thing next time I set up my grow. 😁
 
In the big commercial grows the hanging of the lights is done by a company.
Everything is calculated and measured prior to the hanging of the lights.

i know. i've helped do it.


If you want to do it on your own, you will need a meter or two.
Even they use meters, before they hand the keys to the grower.
It's like with the irrigation system, the company installs all the pumps and hoses and tanks.
But if you want to do it on your own you will have to read a thing or two about GPH, Pump pressure and things like that.
All I'm saying is that if you want to do it right do it right, because I've had a lot of issues with lights.
And whatever people were telling me was not correct.
And I bet you know how long it takes for a plant to recover from a light/heat stress...
So that's when I decided that a meter would be a handy thing next time I set up my grow. 😁


been working with led before it was commercially available to growers. i was lighting tech in a production company. i know for a fact the meters don't return a proper value unless you're investing in decent equipment. ours run in the 400 - 600 dollar range. no home grower is gonna invest that much.

might as well just get a phone app. they're gonna be close enough for most folk.
 
i know. i've helped do it.





been working with led before it was commercially available to growers. i was lighting tech in a production company. i know for a fact the meters don't return a proper value unless you're investing in decent equipment. ours run in the 400 - 600 dollar range. no home grower is gonna invest that much.

might as well just get a phone app. they're gonna be close enough for most folk.
"close enough" - I have tested Korona and Photone. The first time it was with a blurple and it was not able to give me a reading. The second time I tested it, it read 16% high for all dimmer settings. It was consistent, which is good, but that much of a variance is significant and, lacking a known good source that I can use to calibrate it, I would not use Photone. And, of course, if I get a new phone, I need to go through the calibration process again.

OTOH, I have tested the Uni-T light meter against my Apogee. I don't know anything about the quality control for that device but I assume that they manufacture "lots" of them and that their sensors and manufacturing processes are of sufficient quality so that a user will get similar readings from one manufacturing run to the next.

For me, I'd recommend going with the manufacturers recommendations, then Uni-T + a conversion factor, then a PAR meter (Spot On, Apogee, or LiCor). Each of those choices have a cost, either direct or indirect, and they all have their advantages and disadvantages.

One goal of all of this is to get the plants close to the light saturation point and then adjust PPFD and DLI based on how the plant responds.
 
"close enough" - I have tested Korona and Photone. The first time it was with a blurple and it was not able to give me a reading. The second time I tested it, it read 16% high for all dimmer settings. It was consistent, which is good, but that much of a variance is significant and, lacking a known good source that I can use to calibrate it, I would not use Photone. And, of course, if I get a new phone, I need to go through the calibration process again.

OTOH, I have tested the Uni-T light meter against my Apogee. I don't know anything about the quality control for that device but I assume that they manufacture "lots" of them and that their sensors and manufacturing processes are of sufficient quality so that a user will get similar readings from one manufacturing run to the next.

For me, I'd recommend going with the manufacturers recommendations, then Uni-T + a conversion factor, then a PAR meter (Spot On, Apogee, or LiCor). Each of those choices have a cost, either direct or indirect, and they all have their advantages and disadvantages.

One goal of all of this is to get the plants close to the light saturation point and then adjust PPFD and DLI based on how the plant responds.
My eyes can see the leaves intaking ppfd ;) :rofl: :oops: :blunt::thedoubletake:


It's called OG vision. I can't read shit. But the leaves talk to me.
 
"close enough" - I have tested Korona and Photone. The first time it was with a blurple and it was not able to give me a reading. The second time I tested it, it read 16% high for all dimmer settings. It was consistent, which is good, but that much of a variance is significant and, lacking a known good source that I can use to calibrate it, I would not use Photone. And, of course, if I get a new phone, I need to go through the calibration process again.

OTOH, I have tested the Uni-T light meter against my Apogee. I don't know anything about the quality control for that device but I assume that they manufacture "lots" of them and that their sensors and manufacturing processes are of sufficient quality so that a user will get similar readings from one manufacturing run to the next.

For me, I'd recommend going with the manufacturers recommendations, then Uni-T + a conversion factor, then a PAR meter (Spot On, Apogee, or LiCor). Each of those choices have a cost, either direct or indirect, and they all have their advantages and disadvantages.

One goal of all of this is to get the plants close to the light saturation point and then adjust PPFD and DLI based on how the plant responds.


i say close enough because no one buys the gear that is accurate. the core issue is the instruments were developed for standard lighting, not led. not all of them work decent for led. a number don't even work in direct sunlight.

if you're gonna get a cheapie might as well get a phone app. it might not work correct but i'm sure you'll feel better about it.
 
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