LED Questions - Distance, Reflective, General

Hello All,

I'm going to be running the Helios 420 watt fixture which actually runs at 375 watts. Other details about the light is they use a 90 degree lens and has 8 - 3W 1 chip cree's in the center of each module. Not sure what else is relevant.

How far above the canopy should I start testing the lighting?

I'm assuming I want to start closer and work my way up. True or false?

Do LED's benefit from reflective surfaces like panda paper?

What is the purpose of the white LED's?

I'm putting 4 of these 420 watt fixture in grow space that is 3' x 10' spaced approximately 11" apart. Can any experts tell me if this level of light saturation is capable of harming the plants?

Thanks

Tom

Thanks

Tom

hi Tom and welcome

first off, distance, I found that my light do best at around 15" and I run a 120x3W panel (288 actual watt)

at 12" it did bleach a few of my top Bud`s at the center of the fixture

also, according to the seller I should keep it at 24" in veg (I use it to flower with) and 18" in flowering

according to my light meter 12-18" also seems best, from 4-6K foot candles (same I had with my 600W HPS but with much better spectrum and next to no heat)



I´ll try to train/arranges my plants so they peak up a bit more at the edges of the fixture


so no, if anything, start a bit off and work em down/closer or just let the plant grow up at em, like etc. start em at 18-20" and allow em to grow up to 12-15" from the light before moving anything

and yes I do use some reflective material (maylor/emergency blanket)



tho, LEDs do not spread out the light much, IME the only "real" down side of LEDs compared to HIDs is that they don't cover as much ground, pretty much one directed, a few inch`s out to the side of the panels and the light intensity drop dramatically, so keep the plants under them, in form of light spectrum, penetration and heat/power they totally blow away HIDs

the white LEDs is "the new black" this year, so to speak, seem like the research in LEDs and the use for MJ have proven that plant don't only need red and blue light to do good, yes it benefits highly from them but it seems like they need more, even yellow and green light seems to do some different, so its pretty nice if your fixtures have some ? (mine have 16x6500K beside the few blue and all the Red`s) as they cover more of the full spectrum

about space your fixtures will cover, well do some experimenting, but don't expect them to provide much light after 5 inch`s out at the end/side so line em up so they do overlap etc

hope this help some

Slip

Hey Slipon, what lens angle did you spec on your panel?

brotherjericho said:

Hey Slipon, what lens angle did you spec on your panel?

Click to expand...

Thanks for all that information and the pics. Any body else want to chime in? Anybody else running the Byson 420 watt fixtures?

Any chance anyone knows how close this set up is going to be to a 1000 hps?

Thanks

Tom

if don't have any light meter of any kind, your going to have to do the "hands" tests.. which is seeing the intensity off your hand.. obviously corners need the attention.. when the plants are smaller you should not worry as much as there is no corners being filled out, once they get bigger you need to take into account the middle is always overpowered, so make sure the sides get enough light pulling up the light to accommodate sides

if it were me, I work from the same as you stated, pulling up, first making sure I have my sides covered, so that will already account for some distance..

yes reflective surface works, also measured with my meter. flat white paint works also. it's not a necessity to get it though, as it's not going to super boost anything, but it does work to reflect light.

white LED was made to try and fill alot of spectrum that's missing in single color panels.. it's also gotten popular with DIY as no one likes the "funky" color light , we want as white as possible when working under lights, and white provides that. every spectrum is hit from 400-740 in white LED ( every single one I've looked at ) , each wavelength is certainly not equal, but with a bonus being that the blue and orange/red is the highest color curves in whites making the future of LED mostly likely a white future.. it has the benefit of all spectrum, and a nice color to work under. also whites are obviously popular being used for replacement for all lighting, so it's getting big bucks for development.. just be happy it's a race with companies to produce the highest whites... that's very good for us.

light saturation, don't know as I have no meter , size of panel.. I can guarantee at 50 watts a square foot, there is really no potential for harm, unless nuking a plant under the light ( getting the panel far to close to the plant ) but I doubt this as you will need to fill side lighting first.. I've run 75 watts a square foot of LED with no harm..