Light burn at 700 PPFD?

I got my new Spydr 2P light and I love it! I of course wanted to push the limits and hung it 12" above the canopy and got light burn. I moved the light up to 30" so it was only at 12" for 3 hours.

It's been over a week since I have had it at 30" and I just moved it up again. My PPFD is at 700 and 730 for the plants that are showing what I believe is new light burn separate from the previous incident. I already have a C02 bag in to help with the light demand but it is just in and still inocculating.

My current PPFD is reading at 650 at the highest and I think will kick the can down the road until the I start letting it go above the SCROG screen.

Any ideas why I may be getting light burn at what I think is a very reasonable PPFD. My thoughts are my PPFD Meter phone app is not of quality and wrong, plant genetics from one to another handling the intensity better and not enough C02... and that's all I got. Whatcha think growers?

Bigger leaf with light burn from light at 12"

Newer growth with light burn on the leaf tips from light at 30"

It takes time to dial in the right distance for a particular strain with these new, powerful LEDs. All you can do is start conservatively with recommended distances by people here who use them, and go from there. Some strains can take more light than others. Also, any time you move a light closer or increase the power, you need to ease the plants into it, just like how you have to "harden off" indoor grown seedlings to outdoor sunlight. I'm talking even 30 min at the new distance to start, then ease off till the next day, then maybe try an hour. Some people go much faster than that, but it's how you avoid light burn. Good luck!

Rurumo said:

It takes time to dial in the right distance for a particular strain with these new, powerful LEDs. All you can do is start conservatively with recommended distances by people here who use them, and go from there. Some strains can take more light than others. Also, any time you move a light closer or increase the power, you need to ease the plants into it, just like how you have to "harden off" indoor grown seedlings to outdoor sunlight. I'm talking even 30 min at the new distance to start, then ease off till the next day, then maybe try an hour. Some people go much faster than that, but it's how you avoid light burn. Good luck!

Click to expand...

I'll continue to dial it in and take a slower approach for sure!

Ironically, I did take two plants out of my indoor grow and put them outdoors at sundown. I think the huge roots played a vital factor in them pulling through the stress! Several feet long and a spread over as many feet!

You can see I took the two middle plants out of the tubs and moved those into my garden and are now looking great!