ttystikk
Well-Known Member
Mercury vapor.
Light ???
- Thread starter RM3
- Start date
Evil-Mobo
Well-Known Member
This kind of bulb to be exact I have two sitting here, not sure who you asked but I will chime in and it did burn my plants.
http://www.htgsupply.com/products/agromax-pure-uv-t5-bulb-4-foot
My 2x4 is actually more like 2.5x4.5 so I used the 3 foot recommendation to cover this area because there was just no way at 2', it would burn my hand holding it at the canopy.
I'm, not trying to sound like @ss although I probably will for saying this, but it is/was nice to see someone more experienced than myself have some of the same issues and observations as me.
http://www.htgsupply.com/products/agromax-pure-uv-t5-bulb-4-foot
My 2x4 is actually more like 2.5x4.5 so I used the 3 foot recommendation to cover this area because there was just no way at 2', it would burn my hand holding it at the canopy.
I'm, not trying to sound like @ss although I probably will for saying this, but it is/was nice to see someone more experienced than myself have some of the same issues and observations as me.
pookat
Well-Known Member
And thats the reason i have bad eyesight.
Damn good lights, had mine about 2 foot away but started uv at pre-seedling stage to get them used to it. had my 2 250w for nine year,still gave a sun tan, then one blew last week, down scaling now to 2 10w U.V Led 365-670nm.
U.V.a encourages mold /mildew spores etc.
U.V b kills most things including people,
if your gonna use U.V of any kind GET SHADES at least....spoken with 35yrs experience
bravedave
Well-Known Member
Evil-Mobo
Well-Known Member
@RM3
Since the thread is just titled light........
My young and new to growing curious mind wanted to ask a question if that's cool, I don't care who replies let keep talking light here.
Would there be a time between veg and flower where more watts is better for the plant than the other? ie: more watts in veg vs flower or vice versa..............? Or does it not really matter......? I am not talking spectrum, just pure watts.............
Cheers
Since the thread is just titled light........
My young and new to growing curious mind wanted to ask a question if that's cool, I don't care who replies let keep talking light here.
Would there be a time between veg and flower where more watts is better for the plant than the other? ie: more watts in veg vs flower or vice versa..............? Or does it not really matter......? I am not talking spectrum, just pure watts.............
Cheers
Last edited:
ttystikk
Well-Known Member
Watts are completely irrelevant; the plant sees PPfD. Increasing light intensity needs to be done gradually enough so the plant doesn't respond badly; this can include increasing intensity in veg, a slow ramp up in bloom, etc.@RM3
Since the thread is just titled light........
My young and new to growing curious mind wanted to ask a question if that's cool, I don't care who replies let keep talking light here.
Would there be a time between veg and flower where more watts is better for the plant than the other? ie: more watts in veg vs flower or vice versa..............? Or does it not really matter......? I am not talking spectrum, just pure watts.............
Cheers
Evil-Mobo
Well-Known Member
So let's say theoretically, you switch a 54wX8 bulb T5, for a 4 COB LED with monos running cree 3590's and cree reds and blues. The LED is pulling a legit 400W at the wall...................I am purposely trying to be vague so this does not turn into a brand a vs brand b debate I know you like to be very specific but please bare with me if this is enough info to answer the question.........
ttystikk
Well-Known Member
So that T5 fixture is producing light at around 28-30% efficiency. MY 4 COB LED fixture pulls 224W from the wall, with no monos. It's producing light in excess of 56% efficiency, or basically double the performance with half the watts. The plants will respond just about the same to both.
Evil-Mobo
Well-Known Member
ttystikk
Well-Known Member
Mine certainly do.
Evil-Mobo
Well-Known Member
Perfect this is the goal of this next adventure for my 2x4.
Thanks again........
I need to get my game right before I can walk into the vert section and start asking questions. You guys don't fucken play around and there's a lot less BS over here then elsewhere the way it should be..........
churchhaze
Well-Known Member
Making up lies. You pulled those numbers out of your ass. Please show me your calculations showing 28-30% efficient.
Why do you have to lie to make T5HO sound better than it is?
Evil-Mobo
Well-Known Member
ttystikk
Well-Known Member
They're similar to SE HPS.
churchhaze
Well-Known Member
I calculated LER for the 3000k spectrum of GE LongLast to be 361lm/W. It's 54W T5HO version has a luminous efficacy of 93lm/W. That makes it 25.8% efficient. You can't just make numbers up as you feel. Please show me which T5HO is 28-30% efficient and how you came up with that range.
Why do you feel the need to make shit up? You don't like the real numbers?
churchhaze
Well-Known Member
If T5HO was 30% efficient, it'd be decent. Single ended HPS wipes the floor with T5HO. It's no contest.
well i never was a sommelier..^ but..we can smell the scent of ardour & fervent from overseasWelcome back bro
@ttystikk
Yes we used the correct UVB lights and we had a good UV meter.
Glass in a greenhouse stops 95% of the UVB.
What issue with harding off? If I stick a plant started in the greenhouse outdoors where there is UVB I do not see any negative effects, except if it is colder outdoors. Even with the work it was only the ones that were to close and maybe got to much UVB that were harmed, but none got any benefit at any UVB level.
-SamS
Originally Posted by neverforget4/20
very informative. Im wondering if you used any meter to measure the UVB you were getting at those distances. Is it possible that the plants were already receiving UVB through the greenhouse ?
Also could there have been an issue with hardening off the plants to uv exposure?
Yes we used the correct UVB lights and we had a good UV meter.
Glass in a greenhouse stops 95% of the UVB.
What issue with harding off? If I stick a plant started in the greenhouse outdoors where there is UVB I do not see any negative effects, except if it is colder outdoors. Even with the work it was only the ones that were to close and maybe got to much UVB that were harmed, but none got any benefit at any UVB level.
-SamS
Originally Posted by neverforget4/20
very informative. Im wondering if you used any meter to measure the UVB you were getting at those distances. Is it possible that the plants were already receiving UVB through the greenhouse ?
Also could there have been an issue with hardening off the plants to uv exposure?
Weird . I have that bulb, been using it and havent seen any such issues. I used it at 18" and currently about 24".
Im limiting the exposure to a couple hours a day. However i have inadvertently left it on for a full 12.5hrs a couple times.