Viparspectra P2000 and distance between LED and plants Tops

[HerbalEdu]

Do you you think 25cm to 30cm would still do it during flowering for 3'x2' tent in term of light dispersion on the greatest width of the tent and heat under the lamp when viparspectra recommand 51cm in flowering for a 4'x2' tent

 

[BigCube]

Not sure about your exact fixture. But all samsung lm301 fixtures I've seen all say 24" away in veg 18" away in flower.
Yours is most likely the same.

Not sure if you want to move it closer or further but I wouldn't go much further than 18" in flower. Closer may be fine too. Most led fixtures can get within 12" before any bleaching happens.

 

[Edinburgh]

I have a viperspectra 600w, I leave at least 32inc above canopy, your light is more powerful I would try 36inc above canopy and see how they react, allso that tent is to small for that powerful light, like I said I have a 600w 2 cycle reflector and it is made for a 4x4 tent your tent is smaller this may be a problem hope not but viperspectra makes very good lights.

 

[BigCube]

I mean it says right on the ad veg=24inch the size of the tent doesnt matter unless you have too much light. And you dont.

A well known and solid formula for led lighting is 35w per sq foot. 4x2=8×35=280w so your light is actually a bit under powered for the tent it is in but shouldnt be a huge deal, you just wont get that good of growth on the sides and corners where the light falls off and your yield will be lower than it could be.

The distance from the light matters because too much light can hurt the plant. Conversely too little light doesnt hurt the plant but will drastically hurt your yield and product quality. If you are under powered you are not over lit. So factory reccomend distance it what you use. If you put say 400w of led in your tent, then you would move the fixture back because it is producing more light and at that same 24 inches it is too much for the plant.

If I was you, I would veg at 24" and flower at 18". I would also look in to getting another 80 to 100w of led in there. It can be done in the cheap. Lmk if you want suggestions.

 

[BigBlonde]

I'd say to follow the manufacturer's recommendations at first. Your 25 watts per square foot may be a bit low, but the watts per square foot estimate is getting smaller as LED lights are getting better.

 

[BigCube]

I'd say to follow the manufacturer's recommendations at first. Your 25 watts per square foot may be a bit low, but the watts per square foot estimate is getting smaller as LED lights are getting better.
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That's why I reccomended 35w per sq ft. Its a widely accepted bar to hit when choosing an led setup. It hasn't changed since samsung came out with its lm301 chips. Even now many cheaper fixtures arent using lm301 chips. So if you're using something cheap it may be that 35w sq ft isnt enough.