Lighting and light scheduling (autos)

Okay so I’ve had my autos under a 100w light for about 2 weeks for 24-0 on Tuesday im getting a MARS HYDRO TSL2000 witch is about a 300w I think, would it be okay to switch them to a 20-4 schedule when I get the new light? Also about what brightness percent setting should I set the new light to? I have 3 ladies in a 24x48x60 grow tent.

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18 /6 would be a Good light schedule for veg and flower for your autos.

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20/4 or 18/6. 18/6 saves energy.

Get a light meter. The Photone app for your phone is reasonably accurate. Position the light where the leaf temp is 1-2*F lower than the room temp. Also, control humidity for the room and leaf temp: VPD Chart

That will reduce heat stress and optimize transpiration.

Then adjust the rheostadt until you get 400-600 PPFD on your light meter in veg. 800-1000 PPFD in flower. That will optimize photosynthesis.

Check these measurements often as the plant grows into the light. It will need adjustment often. Far more often than water or feeding.

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I’m with @kellydans 18/6 should be good
And you can started to 70% of you light went you plant be in flowering stage 100%

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Thanks so much for the info @MH47! Been trying to get this type of info from…some other forums. I’m going to have to get the light meter app.
I’m pushing 2- 100w. (ATREUM Hydra 1000) Q panels down to 10” in a 20x36” tent with good venting and 2 plants. Thinking that going to a 250-300w would have to run with more heard room so as to not be worth the expense. At @10” I’m likely getting @1000ppfd in the center half of each plant. I’ll get the app and check. What do you think?

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The higher the light the more even the intensity will be throughout the footprint. The higher the dimmer is turned, the more heat will be generated in your area. Expect to fiddle with this all through the grow, while never achieving the optimum height / dimmer setting. Get the app - it’s reasonably accurate and helps a ton.

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For the TSL2000 you will need to buy a light type option to use the Photone app. “Sunlight” is most recommended for LEDs on the forum. I have purchased both “sunlight” and “LED” and don’t see a whole lot of difference. If memory serves, they were each about $5.

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It was a game changer getting the app. Less guess work. :blush::v:

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I agree with Dr Woo. It’s a balancing act that require continuous adjustment as the plant grows. …but after a while it’s second nature and just something you do.

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They are each 5$ or you can pay 5.99 monthly and it lets you use all the different types! :slight_smile:

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You will like the tsl2000 I started out with the same setup and I got a 4x4 tent and another tsl2000 and I love it happy growing :v:

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Okay so I got the light meter on my phone what is this defuser paper thing it’s getting me to do?

The diffuser is a ribbon of printer paper you loop over the front camera of your phone. It diffuses the light to get a more accurate reading on iPhones. Android doesn’t need them usually.

Just cut a strip about 3/4” wide, wrap it around and tape to itself. Then you can slide on and off to reuse.

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22# paper for best results with photone app.

Photone indicates in the FAQs (I think) that they got very good results using the Pen+Gear 20 lb 92 bright paper, available at Walmart. It’s the version in the blue wrap.

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I found that 22# paper was a bit closer to my Apogee quantum sensor readings, but 20# was pretty close as well.

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Processing: image.jpg…
Good?


It’s on 25%

Swipe right to get from measuring in “fc” to PPFD. PPFD is the measure of light right now from where you’re measuring. A swipe left will take you to DLI, which is the total light for the day (you’ll have to set the hours your light is on). At this stage you should probably be around 300 PPFD with DLI somewhere in the high teens. As the plant gets bigger / older the numbers go up.

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