Plants looking good maybe ad more plant for veg ?
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@drk204 so what I did to dial in my light was I used a light meter on my phone to adjust its power so the plants receive the correct amount of light. Do you have a smart phone, and what kind?
I use android and used an app called PPFD Meter to do my adjustments. I found a chart online of my lights expected light output at a certain distance and calibrated the app using that, which then gave me an idea of how high to place my light. Plants need different DLI (daily light interval) depending on what stage they are in.
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@Randy_Marsh not sure what you mean, sorry first time.
@Dankloud if I did this right and settings are right the meter you said to use says 565PPFD AND 48.8 DLI again don’t know if I have settings in app right. And when does the only 9 rwplys go away lol I think I’m getting close to that now so trying to stack answers.
No worries my statement isn’t clear , do you have 1 or 2 tents ?
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I have 2, 2x2x60, that one has the two cheese plants, and the other has 3 White Widow autos that just poked thru soil yesterday. Will have another light for other tent this weekend, well brighter better one anyways. New one will be 300w for the white widows.
Were you able to find a light map for your light? Do you have an android phone? I chose this app specifically because it has the ability to be calibrated.
So let’s say your map say at 18" you should get 800 ppfd at 100%, when you use the app, hold your phone at 18", if it says 850ppfd, you can calibrate the app with an offset so it reads correct at 800.
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I did find it and according to map it’s a bit low, says should be 950-1066 at 18" but light isn’t on max either so I will turn it up all the way and do as you said and calibrate, much appreciated.
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Anything exhausting the hot air out? As @beardless said, leaf temp. I personally like a max around 82 and low around 68, keeping it that way under less than desirable conditions is a choir. I grow in a garage closet. Different strains also prefer a different range of climates. I’ve actually hit 98 with photos in my closet when I started indoor growing and they survived. Great thing about weed….resilient as hell. 
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No worries man. Yeah turn the light up to max then do the test. Then from there you can lower the height/power to get the best coverage.
Lets say I have one single plant in my tent. Only 1 foot tall. I can keep the light up high, but I would have to make sure the light power level is high enough that the plant receives enough light. Doing it this way with the light exceedingly high means you are also throwing a bunch of photons around to the sides of the tent. While they do get bounced back to the plant eventually, you can actually just run your light at a lower height and decrease its power, as long as you don’t get too close to start burning the plant, and you stay within a reasonable DLI rate. Then as the plant matures you can increase the light height and power as needed. This is also a good way to help with heat since you can run the light at a lower power! Also if you look at the map for your light, you can see that the PPFD decreases as you get farther from the center of the light, so just something to think about as you balance the two.
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I forgot one piece of crucial information. With DLI above 24ish I think, you have to start adding C02. So don’t worry about going that high.
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@OGIncognito yes the larger lower black fan is pushing air out of lower window as the other two circulate it towards the exit. I found some inexpensive inline fans I may get just to help exhaust the heated air, one per tent at base vent holes. They don’t seem to mind the warmth at all really.
@Dankloud copy I will be playing with light etc so when 2nd set of plants is ready will be all set and ready to go. Goal is to move everything into a 5x5 in a few months, just waiting to see how all this works out. As of right now I’m pretty sure this is something I will continue to do, keeps me out of trouble, well kind of lol.
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Right on Bro, I’ve 3 of the inline duct fans. Inexpensive and work great. I’ve got 1 in the top of my closet helping exhaust air beside an AC Infinity 6”. I also use 1 to pull in cool air when the ambient temps are cool enough. You’re right though, your ladies haven’t shown any signs of stress. Nice set up Bro!
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I believe DLI of 24 is closer to the minimum required during flower. CO2 supplementation may be beneficial at 2x that DLI and necessary at 3x
PPFD of 700 over 18 hours produces a DLI of about 45
PPFD of 700 over 12 hours produces a DLI of about 30
The following is from mammothlighting article Optimal Light Intensity
“If you want to maximize yield you need to push it hard with light”…Dr. Bugbee Utah State
Bottom threshold for optimal growth and photosynthesis is a DLI of 22:
24/0 schedule: 254.6 micromoles/m2/s-1
18/6 schedule: 339.5 micromoles/m2/s-1
12/12 schedule: 509.25 micromoles/m2/s-1
The Top threshold for optimal growth and photosynthesis is a DLI of 65 moles per day.
***Extremely important notice, only go up to these amounts if you are using supplemental CO2, do not go this high if you are not using supplemental CO2 as you will actually slow down photosynthesis and waste energy.
24/0 schedule: 752.31 micromoles/m2/s-1
18/6 schedule: 1003.08 micromoles/m2/s-1
12/12 schedule: 1504.6 micromoles/m2/s-1
The generally accepted guidelines for artificial light PPFD in flowering during 12/12:
PPFD of at least 510 micromoles/m2/s-1 for the low end of optimal intensity
PPFD of at least 800-1100 micromoles/m2/s-1 for optimal lighting WITHOUT additional CO2.
PPFD of at least 800-1500 micromoles/m2/s-1 for optimal lighting WITH additional CO2.
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Yeah I’ve seen all this before. Wasn’t sure what that figure was lol
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@beardless @Dankloud @Randy_Marsh @Dr.ofSmokology @GreenSnek @Mark0427
What happened to the days of stick plant in ground, grow dry, smoke. It has become a Science lol. I like technology as much as the next guy and tend to get really involved and truely enjoy the technology of this new growing, but I am an Old Schooler thru and thru. I like my 60’s-70’s music, old cars(real cars made of real metal and a 4 barrel Carburetor) headphones that make you look like Mickey mouse not just jammed into your ears. And weed has always been there, even that has gone “scientific” with different strains, etc, but in the end Puff Puff Pass will always be the best motto.
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Yeah there is a lot of science going into it now. I tried to omit as much information as possible when I was telling you about how to set your lights because I didn’t want to confuse / agitate you with a wall of numbers and acronyms lol. Thank God we put science in to this though or we would never have known how much better we can grow it!
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Agreed, I could of never back in the day thought I would have a plant, an AUTO plant which was un heard of, flowering in less than a month. I love learning the how’s and why’s and I will say it again, ILGM Forums are hands down the best place for info and help.
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I know what you mean. The light stuff is a little nuts. Some of the basics is good to know so you can make reasonable comparisons to evaluate a light. Once you know what the light is, turn it on and move on.
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Just did some tweaking on the lst to open things up, so many lower flowers were not getting much light but this really opened it up. Hope they don’t mind.
@Dankloud @Randy_Marsh @Dr.ofSmokology @beardless @OGIncognito
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nah they will thank you for it with more bud.
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