Lighting Distance from plants without lenses/reflectors
- Thread starter KonopCh
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Nice thread @KonopCh
Only the other day was I talking about this with a member of the Northern Grow Lights team.
I'll see if I can get them to post their experiences with their COB builds here to add to your data.
We have COB with reflectors, glass lenses & silicone lenses.
We are also using different chips from CREE and Citizen.
We also run our COBs at different mA too.
It is gonna be a little while before I start my grow but when I do I'll add my heights.
I'm running Cree CXB3590 too but at 2100mA with a dimable driver.
Only the other day was I talking about this with a member of the Northern Grow Lights team.
I'll see if I can get them to post their experiences with their COB builds here to add to your data.
We have COB with reflectors, glass lenses & silicone lenses.
We are also using different chips from CREE and Citizen.
We also run our COBs at different mA too.
It is gonna be a little while before I start my grow but when I do I'll add my heights.
I'm running Cree CXB3590 too but at 2100mA with a dimable driver.
Can't wait.
First 3-4 days I hang them at 50cm, then I hang them at 40cm. This is my first grow from seedling (I only use COBs last grow from day 35-40 till the end). Seedlings are happy, but you know, we want (to know) optimum.
First 3-4 days I hang them at 50cm, then I hang them at 40cm. This is my first grow from seedling (I only use COBs last grow from day 35-40 till the end). Seedlings are happy, but you know, we want (to know) optimum.
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CXB are strong lights and my last grow I only used 1400mA and they were still good and bright.
I think putting the up a bit higher may be a good idea.
You can produce very short stocky plants if the light is too close.
For me that plays in to my hands as I have a very distinct grow style that not everyone would want to use.
If the lights are too close you will find that you get very short internodes even after stretch.
Although the short skeleton was not grown under COB light and I used my AF-SOG technique the sam sort of structure will happen if you COB is too close.
The Short skeleton (Stem) was actually 12" in height at chop yielding 2.75 OZ (the same height as the ruler.
For interests sake the big stick was from a 9' Sativa.
This is the 12" girl as the skeleton above to give you an idea of what she looked like with her clothes on!
I think putting the up a bit higher may be a good idea.
You can produce very short stocky plants if the light is too close.
For me that plays in to my hands as I have a very distinct grow style that not everyone would want to use.
If the lights are too close you will find that you get very short internodes even after stretch.
Although the short skeleton was not grown under COB light and I used my AF-SOG technique the sam sort of structure will happen if you COB is too close.
The Short skeleton (Stem) was actually 12" in height at chop yielding 2.75 OZ (the same height as the ruler.
For interests sake the big stick was from a 9' Sativa.
This is the 12" girl as the skeleton above to give you an idea of what she looked like with her clothes on!
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I agree with arty there is allot of variables with the distances of cob to cob and driver current.
With my 450w lights I start them at 36 inches and raise or lower by reading the plants more importantly. When they taco/canoe or show serrated edges it's to close, when they are up and perky I drop it just a little each day till I find their sweet spot. I have spent hours doing par readings of different lights, the difference an inch makes is unbelievable. For instance 12" may have a reading of 1200 ~umoles while 18" has a reading of 500~umoles. Optics vs bare cobs can increase or decrease the center by 50%. So it really is based on each specific situation.
With my 450w lights I start them at 36 inches and raise or lower by reading the plants more importantly. When they taco/canoe or show serrated edges it's to close, when they are up and perky I drop it just a little each day till I find their sweet spot. I have spent hours doing par readings of different lights, the difference an inch makes is unbelievable. For instance 12" may have a reading of 1200 ~umoles while 18" has a reading of 500~umoles. Optics vs bare cobs can increase or decrease the center by 50%. So it really is based on each specific situation.
There is nothing wrong with that! More importantly is keeping an even canopy. Ideally keeping all of your buds at the same height the better the light will be across the entire plant.CXB are strong lights and my last grow I only used 1400mA and they were still good and bright.
I think putting the up a bit higher may be a good idea.
You can produce very short stocky plants if the light is too close.
For me that plays in to my hands as I have a very distinct grow style that not everyone would want to use.
If the lights are too close you will find that you get very short internodes even after stretch.
View attachment 658677
Although the short skeleton was not grown under COB light and I used my AF-SOG technique the sam sort of structure will happen if you COB is too close.
The Short skeleton (Stem) was actually 12" in height at chop yielding 2.75 OZ (the same height as the ruler.
For interests sake the big stick was from a 9' Sativa.
This is the 12" girl as the skeleton above to give you an idea of what she looked like with her clothes on!
Yes, I know about tacos.
In veg, when plant is bigger is easier to read plants needs.But young seedling first 7-10 days maybe don't look like taco.
Can PAR meter be bought online? Which one? Need that toy.
And while you are asking, cant you do this with a dslr or light meter for Photography? Asking as I don't know how but I think someone once mentioned it somewhere. That would be a danged helpful measurement for setting up new lights.
I'm not familiar with that. I have an hydrofarm from amazon. 120$ and seems to work well. Whooweee that's in ~umoles
