The biggest mystery in my modern time has been how to gauge my lighting intensity… enter DLI. I have photone but have yet to set it up… can anyone point me to basic resources on optimum numbers and methods? Posts here are quite long on this subject and information scattered. If its like everything else I’ll get it wrong before I understand it well enough lol
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I’ve recently been using the Photone app, and here’s my understanding.
First it depends on what phone you have; Apple or Android.
If you have an Iphone, you need to make a diffuser out of paper to place over the front camera. Videos I’ve seen have demonstrated that the paper should be lifted off the lens itself by a little bit, 1/4" or so maybe. The app typically requires no calibration from what I’ve seen, and most agree to use the “Daylight/Full sun” setting when taking readings. I’ve never tried it, as I have an Android.
Since the hardware that runs Androids are made by many different manufacturers, the cameras all read differently, so the app will need to be calibrated, either by comparing it to a “real” light meter, or by finding the PPFD chart map for your particular light you’ll be using your device under and entering into the app the correct number when taking a reading at the coordinated position according to the chart map. That will set up a custom setting in the app that you would use from then on.
Then there’s all this:
The spectrum of light important to plants (400-700nm) is called Photosynthetic Active Radiation (PAR).
Photosynthetic Photon Flux Density (PPFD, or PPF) is the metric used to measure PAR. PPFD is changed with a light dimmer, or adjusting the distance to the plants.
The Daily Lighting Integral (DLI), is a number standard for a 24hr period of PPFD. The DLI will change based on lighting schedule. A 12/12 schedule will have a lower DLI than an 18/6 at the same light intensity (PPFD), because the sum of light for the day will be less. (Evident in the charts posted above.) This makes DLI the culmination of measurements and is the most complete representation of how much light plants are receiving.
Hope some of this helps. Good Luck!
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Great info from @Bubbala and @Retiredoldguy
I personally try and get closer to this graph from the top chart on this thread.
Start using DLI
It is very long but worth the read
Also, we all get it wrong in some way. With so many different ways to grow, everyone having a different style, environment, and setup forces us all to adapt to what we have. It’s kind of like a weed does in Mother Nature. You will find what works!
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Thanks guys! Great info. So its seems that I’m running about 60 at canopy. I have 4 vivosun aerolight 100 running at 69%. I’m not running co2 so what would be the consequences of running it that high? According to the chart I should be at 45.
Is that with the calibrated Photone app? I looked at the PAR map Vivo put on Amazon and ran it through an online DLI calc and came up with a DLI of 54 at a 12" height with 100% power on an 18 hour day. I guess it would make me double check the calibration if it is. This is what they had up:
Interesting! But is that considering that i have 4? Don’t know if 4 is 4x as bright. Don’t think it’s that linear.
But calibrated? I put the paper over the camera. I’ll have to look at it closer lol. Knocked it to 46% to get to 50 in the middle. And 40 on the edges
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Oh ok, you must have an Iphone. Gotcha.
I doubt it’s 4x, but yeah, multiple lights are usually better than one big bright one because they do overlap and add up, so I suppose 60 is possible. The picture really helped. 
They sure look cool. Curious to see the lifespan of the fans.
I’m curious as well! They made a bit deal about it in promo material. I’ve had 2 oscillating fans go bad. The motors would shut off when it got to a certain position… but these, of course are stationary.
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Does anyone know the consequences of running too much light is? I just learned ( midwestguys post) about foxtailing towards the end of flowering. But provided the extra light isn’t causing heat stress, would it be helpful or harmful to run them full bore? Probably won’t but trying to learn about cause and effect.