How is it someone grows in his garden close to a street lantern and has no light stress, while the slightest leak into my tent stresses them alot??
Street lights absolutely will cause issues. Don’t know how you got that idea. …
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I thought I remember when I was growing my first weeds in the midle of a little town in my garden, there where street lights, not too far maybe 30m.
I wouldn’t look for it, because i didn’t know at that time.
They got robbed lol, 2m tall bushes full of buds, did they hermie???
We will never know…
So many people grow on their balconies…
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I have heard that even the tiny little light on the timer can cause issues.
Genetics, and the disparity between the intensity of the sun and the intensity of a street light/moonlight.
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Ok i get that… What I said above was in that line of thinking…
The disparity between my hps and a tiny little led on a timer to me seems bigger than the sun / moon.
What unit would we measure that disparity in?
Lol. No.
Seems is the key word there. The human eye adapts to a wide array of light levels, but that means we’re really really bad at sensing disparity. I’m forgetting the exact values, but if I remember correctly moonlight is 1/400,000 the intensity of direct sunlight.
As far as the street lamps go, distance is also very important. You estimated 30 meters. It might well be that the plants would be affected by a street lamp if it was directly over them (4m?) but at 30 meters the inverse square law reduces that light intensity down to a minuscule amount (~1/36).
Looking at it another way, the 1000w HPS bulb we’d use in a grow room puts out about 150,000 lumens. At 30 meters it’s 160.
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How much lumen does the sun emit?
how much the moon?
how much the tiny led?
Did you read my post? It just seems like you aren’t understanding the concept of the inverse square law.
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Yes and to answer my question i would need to know how much lumen the sun emits(well it propably is more important how much lumen hit the measuring point) … With that knowledge i could calculate how many lumen the moon emit…
now i only ned to know how much lumen a little light on the timer emits, and we could at least mathematically say: “a little led on a timer shouldn’t affect your grow.” or it does…
The moon delivers 1/300,000th the light of the sun.
Genetics as stated play a role. Some plants don’t care. I don’t and never have maintained absolute light-tight grow space and never had a problem. But streetlights are a different animal altogether.
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So you are saying that the light in the growroom, has to be at least 300000 times stronger than the led on the timer so it won’t influence the plant?
98 000 lumen per square meter reach surface on a sunny day with the sun directly over that square meter…
Now im getting confused… My hps is stronger than the sun???
I’m not suggesting that there’s a formula for it, but it’s empirically proven that some plants can tolerate nighttime light when night and day lights are of very disparate light intensities.
I used lumen because I was referring to visible light. It’s not especially great at quantifying intensity of different light sources. Photovoltaic radiation is what you’d really want to measure. An HPS bulb is not a stronger light than the sun in a very literal sense. Maybe the white sheet says it produces more lumen than the number you cited, but the number you cited is a measurement of the sun’s light at a distance removed from the sun.
Remember what I said about the inverse square law. If you meter the photons at 1 foot from your HPS bulb, you get 1000/sec (a random number). At 2 feet, you read 250/sec. At 4 feet from the bulb you measure 62.5 photons per second.
If I’m standing in a sunny meadow, or 100’ higher up on a hill, it’s of little consequence as far as photovoltaic radiation levels are concerned. Compared to your bulb, the sun’s photovoltaic radiation, or photons per second, is consistently stronger.
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Just eliminate the light pollution in your grow room
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Uh, no, Look at what you wrote. That’s not even close to what I stated.
If you’re sitting right on top of it yes! Again; comparing apples and oranges.
Just try to eliminate any spurious light source when using hybridized cannabis indoors. It’s pretty simple and you don’t need to waste any extra brainpower on it lol.
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Sit in your dark empty tent with room lights on for 20 minutes. Leave all devices on inside the tent (except grow lights). Leave all lights on in the room outside the tent. You do that without looking at your phone, and you’ll see even the smallest leaks. Then cover them with black paint, thick black duct tape, etc, and test again.
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“Just eliminate the light pollution in your grow room”
1 vote for best answer in the thread 
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I don’t have any 
It seemed the math doesn’t add up with hps and tiny led, vs moon and sun.
Nevermind
I have had many many light leaks throughout grows never had 1 herm… I feel if you consistently have a “moon” in your rooms and it dosen t change you are ok but if you got room lights comming on and stuff like that that’s not regular dmevery day that’s what gets you
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