400 HPS Optimal light pattern

[Gastanker]

As long as you can deal with the heat you can get is as close as possible. Here's a 600w 4" from the plants? My side lighting shouldn't change anything - that's all UV, doesn't contribute to growth much. Theres just no way you're going to evenly cover a 3x3 area with the light in a euroreflector 6" from the canopy - not enough distance for it to spread out imo. But if you have a 2x2 canopy keep it 6" by all means.

 

[massah]

well not sure on his info but i do as he says not to do and dont get those issues. and those pics cant be realy used as a ref here as there is side lighting so all this is out the window. i also run a 600 and tops are about 6 inch all the time. and a 400 i let them touch the glass. no burns no bleaching non of the issues other say. maybe its them and not the light distances

Ever try testing it out for a grow at a further away distance? You might just be having reduced yields because of how close you have them? Or maybe the strain you are running loves as much light as you can throw at it? The things we tell people are general rules of thumb...not hard fastened in concrete rules to follow...if some noob comes by and sticks their plant 4" from their 400watt HPS they are going to burn the shit out of it and ask why...this dude told me to do it...so...its better to urge on the side of caution when giving advise on how to grow, or you'll end up with people bitching at you because your advise killed their grow

 

[Cannabisworks]

lol..im not having reduced yileds. i get what hydro guys get and im in soiless and very little foods. just seems most are afraid to stray away from old outdated forum info
well anyone following that chart will flail as well as you say with my info as its no explaining anything to me. and ive yet to do any damage from my advice. i wouldnt just toss a chart or basic post. i try and explain the how and why`s

 

[Gastanker]

Ok, I measured my hood (same as the OP's). Due to the extreme angle of the euro reflector, reflected light will not cover a 3x3' area until it is 16" from it.

 

[massah]

lol..im not having reduced yileds. i get what hydro guys get and im in soiless and very little foods. just seems most are afraid to stray away from old outdated forum info
well anyone following that chart will flail as well as you say with my info as its no explaining anything to me. and ive yet to do any damage from my advice. i wouldnt just toss a chart or basic post. i try and explain the how and why`s

You need to go talk to the guy who puts his 26watt CFL's 10" away during veg and said he wouldn't put them any closer because it was too bright...My 150watt HPS lights start to burn tips within an inch of the glass covering it(no cooltube)...when dealing with so many people on here that burn their shit in a blink of an eye...most don't have the money to invest into proper cooling(like me so far)...its a balance of evaluating your perception of the growers situation and experience and providing a mid-ranged response that they wont fuck up...and if they do fuck it up...they are retarded and should stick to buying a bag

 

[Cannabisworks]

hods kill out footprint and colours big time. im using maverick suns and have same issues. light pattern drops down straight from edges of hoods to make a smaller footprint, but concentrates my lumen output to a tight area with less loss at this distance. have been getting 3 to 4 oz depending on strains form 1 x 1k and 3 foot plants
im down to multi 600 now

 

[Cannabisworks]

well if you havent got the right venting but your saying where wrong???..didnt we say the room conditions played the biggest role??..maytbe buy the right stuff instead of saying werre wrong. htis is usulay the reason. not the light.....the grower

 

[Cannabisworks]

best advice id say s its determined by room and conditons and growers ability but we do want to be as close as we can. to the point where we may burn from to much uv...and we dont know that as we dont know what bulbs the person would be using and all are diff

 

[Gastanker]

From side lighting to side lighting is 3'. Look at this terrible angle (super regret reflector choices).

And from the glass to where it hit on the wall Looks like 17" in the picture but it's really 16"

Notice how the level of the light is higher than the angle of the reflector? This means that there is some low light getting through but it can be misleading due to low intensity. This is the reason I aim for my canopy to be ~ 6" below the point the light hits the walls.

 

[Cannabisworks]

side lighting wont change anything? changes everything. now there is more penetration under the canopy. im not dissagreing with your ways as i believe you said keep as close as we can...same as i do

 

[Gastanker]

side lighting wont change anything? changes everything. now there is more penetration under the canopy. im not dissagreing with your ways as i believe you said keep as close as we can...same as i do

Keep in mind that the amount of light the plant receives has nothing to do with lux or lumen but instead with PAR - the wavelengths that the plants can actually use. My side lighting is all UV reptile bulbs. While these bulbs effect the trichomes they have pretty much zero impact on the growth of the plants - it's the wrong wavelength. It's like having a single 150w incandescent bulb - can't grow a single plant with that.

 

[massah]

well if you havent got the right venting but your saying where wrong???..didnt we say the room conditions played the biggest role??..maytbe buy the right stuff instead of saying werre wrong. htis is usulay the reason. not the light.....the grower

nevermind man...i never said you were "wrong"...go grow your shit...you've got the money and equipment already so you do what you do...

 

[Cannabisworks]

what makes you think i have the money...lol..im on dissability and im no dealer.

yes i know plants dont see the lumen. but thats what the chart says so i use it. has no data on par or anything else...ok not saying were wrong bud...saying you dont agree then. or feel the chart is factual in the real world of growing

 

[Gastanker]

The chart needs to be taken with a grain of salt - same with everything on this forum. I'm not trying to address the chart, just help the OP, who is growing with the same hood as me, in the same size area. I wouldn't suggest covering a 3x3 area with a 400w tbh, but if you are and are using a euroreflector, I think you will want to give the light some spread. No point in having plants covering a 3x3 area and then only illuminating 2x2 of it.

 

[Cannabisworks]

yup all grow stuff needs to be taken that way as no 2 growers or grow rooms are the same. agreed on the hood. and depends on hood brands to light wattages also. i have had an old old one gave mne great foot print withloosing the concentrated lumens. for me my 600 in mavercik sun hoods give me about a 3x3 footprint

 

[guy incognito]

that chart has been online for years and is totaly wrong. how does light gain lumens at a further distance form a bulb. it diminishes not gets brighter. that shows all get brighter the further away
it shows for a 400 watt we get 53k lumens and is about right. then at 4 inch i assume or is that foot..then it jumps to 151k...the output of a 1k bulb. how do they beat inverse square law? you cant.
1 foot from a light source and we only have 25% of the original lumens.
basicaly a 400 is only good for 18 inch total. 600 is about 22 inch and a 1k is about 24 inches to keep good light penitrations. this isnt to the canopy...its total light to the floor.
at 1 foot from a 400 watter at 55k lumens is now only about 13k lumens..pretty lame. should be running a 400 about 4 inches from a hood. mine touch the glass now n then i keep so close. no it wont burn if you have correct venting. this is why othersw need to be so far away. most go cheep on room venbting or conditions.

Different units dude. The values in the top row highlighted orange are the total lumens output by the bulb, below that is the wattage of the bulb, then below that is foot candles. A foot candle is lumens per square foot.

 

[Cannabisworks]

lol...put the bong down..lol..i didnt even notice that. ok ill eat my words i can admit that. fak me maybe i do need glasses.
thx for pointing that out.

 

[massah]

lol...put the bong down..lol..i didnt even notice that. ok ill eat my words i can admit that. fak me maybe i do need glasses.
thx for pointing that out.

You know whats sad? I read it wrong too LOL

 

[HighLowGrow]

Whats really really sad is so did I.

 

[Cannabisworks]

hey...gimme my bong back then., ...lol