Daily Light Interval (DLI) is a quick and efficient way to calculate how much light our plants are receiving within a 24hr period, allowing for easy light adjustments. DLI will help you and the community to better understand your lighting in a more universal term, leading to clearer communication of what the true light value is. Almost all smartphones have the ability to use an app (we will get to this don’t jump the gun) in order to calculate DLI, and if that is not an option a cheap LUX meter can be purchased which will allow us to do some conversions in order to obtain a DLI. However this is not exact science, think of it as more of a way to measure and have a baseline to go from while speaking in a universal language. Why? Height is A terrible measurement to gauge lighting. As my hero Bruce Bugbee explains here at marker 5:30, extensive video be warned. Dr. Bugbee shows how lux is not a truly accurate measuring device but without a par meter $$$ it’s the second best we have readily available to us, the First is our specific DLI app (with modification). [Cannabis Grow Lighting Myths and FAQs with Dr. Bruce Bugbee] Process The first step to this is getting a LUX meter, they are cheap or free if you download one on your smartphone app store. take multiple readings from your canopy (ussualy the edges are the most important noting the center will be the strongest), take the average. THIS IS IMPORTANT, YOU NEED AN AVERAGE. Now put that average lux into a HLG’s lux to PPFD conversion calculator (if you have an HLG) or use one on wave form lighting (first google from LUX to PPFD converter) if you know the type of light your running. Once you know your PPFD then you can type that into a PPFD to DLI converter. This will give you a number, jot it down so you know where your at. Now play with the PPFD number in that DLI converter until you get the right DLI for your growth stage [8FC46ADC-A87D-43E0-80C7-F27CFDECD26C] Go back to the LUX to PPFD converter and find out how many LUX you need to get that amount of PPFD to meet your DLI requirements for your stage of growth. Example Let’s say it’s 55k lux, okay then in your grow room notes beside your VPD chart (if you don’t have one of these you should it’s another topic though) you should have a couple notes that read something like this. Veg = 10k lux = 15 DLI Full power pre stretch = 55k lux =60 DLI Late flower to avoid fox tails is 45k lux = 45 DLI. (this is a total made up example) DLI App Thanks to some collaboration, testing, and no expense spared by our members @Bobbydigital & @Hellraiser we now know the easiest and most accurate way to calculate DLI is with a modern smartphone and an app named “Photone”. The trick to ensuring this app is accurate for iPhones involves taking a normal piece of printer paper and laying it over your phone’s camera to work as a light diffuser (not needed on android phones). Set the app on sunlight mode, do not use the LED modes as they are not as accurate from our testing with an apogee meter. Ensure an average reading of the canopy level is taken, remembering the light will be strongest at the center and weaker at the sides. Now you can dial your lights in very fast with your lux app on your phone and get a good average DLI, which you will want to do weekly until plants stop growing. This chart is a starting point, play with it. Personally I am still messing with my own setup, while we are hearing that Bruce and his team at Utah state have research showing even clones accept very high light values. However in late flower high light values can bring out fox tailing. So personally I like to ramp up to 60 DLI as fast as I can, once I’m in late flower drop down to 45 DLI the second I see a fox tail. The more powerful your lighting the shorter and busier your plants will be, so depending on your grow style you may want more stretch early on to flill a scog or something. Light spectrum also has an effect on plant morphology with the more red causing again a much wider bushy type plant and blue tall and spread out. I personally love growing plants, giving them a FIM at the 4th/5th node and then letting them flower out after veg (I mostly run autos) If your in the garden evey day and you enjoy training your plant you may enjoy less light levels Durring veg unlike me. Here is to plants I hammered with light [20201206_104511] [20201127_201011] Now here is two plants I went a little easier on until post stretch, I really find cranking the light up pre stretch is key to controlling it of course I need more experience with this to say for sure but this is where I’m leaning. [20210220_151714] Try not to run your lights to close as this can cause fox tailing as well. Keep in mind that this is only one part of lighting, which is a very big topic with many variables. This is my modified chart that I recommend to follow if your environment controls are ideal, VPD, fresh airflow, medium, nutrients, and other variables. The chart below has been modified after Dr. Bruce bugbees advice (as I have interpreted it) and my own personal experience as well as my observations over time. This is for both Autos and Photos. [20220422_082846] Summary, ramp up lighting fairly fast avoid long internode spaces and ramp it down mid to late flower to avoid fox tails. If your lights are less than 12" away from buds come late flower you may need to lower DLI more or just be prepared that top buds will foxtails and not to rely on them for plant harvest measurements aka tricomb images with a usb/Bluetooth microscope. @ashhhh @Breezy @Bulldognuts @beardless @PharmerBob @Axemanjake23 @CoyoteCody

@Low is that a crab net, what’s is the green deal, or where you find that at, zip tie works wonders? But mark your post for your scrog and from the looks :eyes: of it, you might have to readjust the screen are put a second one in there, you have them high power lights right, they might stretch about 12-16 inches minimum ?

If I have to add another layer I will. Right now I’m gonna just be tucking, I’m going to use it to fill most if not the entire canopy. :v:t3::sunglasses: [image]

@Nicky so, I’m veging this 3 week old plant under my Mars hydro ts1000. I’m at about 35% power so about 52watts. 18” from canopy. Temps are 73f day and 66f night. With 60%rh. According to the Photone app, I’m at 14 DLI in the center which is where the plant is. With 6 nodes so far and it’s only about 5” tall. Would you say that it’s getting enough light for right now? [image] [image]

I’m not familiar with the apps. Maybe I need to go through these apps and find out which ones claim to calculate DLI the compare it to my lux app. In any case looking at the node spacing @Jake3 it looks good. I wouldnt give it any more. If you do plan to transplant that again burry more of the stem those bottom leafs will fall off soon. But plant looks good. You will get better growth at 78f What are your settings on the app? Did you set it to direct sunlight? @BobbyDigital I think tested this app and it needs to be set to direct sunlight with a piece of printer paper to be used as a diffuser (but maybe not any more updates?) Looks like the app has a mode that will auto detect light temp. I’m going to see how that works on my 3500k w reds. I’m not at home and may not be able to test this for like 3 weeks but I’ll try to remember

I have had the app set to the spectrums for the Mars Hydro just to play around with it. The last time I used it was in the beginning of my last grow and it seemed to have served me well even if it wasn’t accurate. Lol. I’ll try switching it to sunlight and use the diffuser again to see what the change is. When I transplanted this one a few days ago, I had buried it right to the coty leaves and the little stinker just kept growing up. And to raise my temps, I’ll try raising the light and turning it up. I don’t really want this one getting tall as I plant on making it as bushy as possible since it’s the only one in the tent. Thank you and thank you @BobbyDigital for doing the leg work to see what the accuracy is on the app!

I would suggest using the lux meter (no diffuser) and wave form lighting convertions then comparing it to the DLI app. That way you will know if it’s accure. I unfortunately won’t have time this weekend, 3 days at home and they are sooo fully packed between taking my girl on a date night out of town and dealing with a. Ton of errands whole still trying to squeeze in plant stuff! You seem to have your focus on the right things and that will pay off I the end.

@OlyBoy98503 this is the thread that @Nicky started about setting up lights using DLI and increasing or decreasing DLI based on plant needs at different stages. There’s a lot of really good information here.

I’m looking at the DLI chart and had a question. It shows the recommended DLI listed by week on a 14 week schedule. How are you adjusting your numbers for different strains? For example, week 7 for an auto Sour Diesel might be completely different for a photo Blue Dream. [image]

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Indoor Growing Lighting

BobbyDigital July 20, 2021, 9:32pm 164

Yep I use direct sunlight with a diffuser. That’s the setting that came the closest to the apogee meters.

Excited newbie here! 4x4 indoor

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