When to turn up the lights?

[hightech316]

I have a medigrow Sun-2 320w .
Plant is within first week of veg .

Did not come with explicit instructions pertaining to light intensity and plant stages .

There is 40,60,80,100% option .

Right now , I'm at 40% and 24" from canopy.

When should I bump up the power ?

 

[growmie]

I have a medigrow Sun-2 320w .
Plant is within first week of veg .

Did not come with explicit instructions pertaining to light intensity and plant stages .

There is 40,60,80,100% option .

Right now , I'm at 40% and 24" from canopy.

When should I bump up the power ?

Have a Photone app on ur phone? Measure ur PPFD make sure its between 300-600 PPFD and ur good to go. 24" should be fine.

 

[hightech316]

Have a Photone app on ur phone? Measure ur PPFD make sure its between 300-600 PPFD and ur good to go. 24" should be fine.

Thank you , I will have to grab one!

40% seems pretty decent for seedlings . Iroughly 105w

 

[Blastfact]

Thank you , I will have to grab one!

40% seems pretty decent for seedlings . Iroughly 105w

GG4 two weeks from helmet head. Transplanted at 470 ppfd. Under a HLG 650R

 

[LoveGrowingIt]

Plant is within first week of veg .
...
There is 40,60,80,100% option .
...
Right now , I'm at 40% and 24" from canopy.
...
When should I bump up the power ?

I'd leave it at 40% for a while longer. A picture would help.

Recognizing the signs of light stress (or burn) can be more useful than a light meter. Watch for the signs after increasing the power, and if you see them, reduce the power or increase the height of the light.

 

[Natep]

Look at your plants right before lights out. If they look like they are praying add more light.

 

[PooToe]

GG4 two weeks from helmet head. Transplanted at 470 ppfd. Under a HLG 650R

View attachment 2323793
View attachment 2323794

Nice meter. Was it expensive? I use my tent buddy app and it seems to work fine but I've always questioned how accurate it was and it degrades over time. I checked my phone app against an Apogee meter my buddy has and it was pretty close but when I checked it again it was off by a larger margin.

@hightech316

This chart should get you in the ballpark...

 

[Blastfact]

Nice meter. Was it expensive? I use my tent buddy app and it seems to work fine but I've always questioned how accurate it was and it degrades over time. I checked my phone app against an Apogee meter my buddy has and it was pretty close but when I checked it again it was off by a larger margin.

@hightech316

This chart should get you in the ballpark...

View attachment 2324012

I gave up on the cell phone crap apps. I tried them on two iphones and several droids. They couldn't hold calibration and read all over the place. Once I popped for the real meter it became clear just how bad the cell phone and apps really are. The meter was not cheap. But good tools are never cheap..

 

[Natep]

I gave up on the cell phone crap apps. I tried them on two iphones and several droids. They couldn't hold calibration and read all over the place. Once I popped for the real meter it became clear just how bad the cell phone and apps really are. The meter was not cheap. But good tools are never cheap..

I agree now I only read the plant. They will let you know when they are ready for more light.

 

[Blastfact]

I agree now I only read the plant. They will let you know when they are ready for more light.

I read plants for decades. And honestly,,, I'm sick of it. While reading is all about cause and effect,,, and useful. I want tools when appropriate. And with todays fufu weed. Lord only knows whats going to happen.

 

[LoveGrowingIt]

AFAIK, the Photone app works well if it's calibrated. I've been using a clip-on "Diffuser & Cosine Corrector" that the Photone folks recommend for my phone. With it, the phone is supposed to be correctly calibrated. Even if it's correct, though, how do I know if the measured light level is right for my plants? Do I trust the charts? I don't think that's good enough. That's how reading the plants is involved. I'm not going to follow the chart if I can see light stress on the plants. There are too many other factors involved to follow the charts alone.

 

[PooToe]

AFAIK, the Photone app works well if it's calibrated. I've been using a clip-on "Diffuser & Cosine Corrector" that the Photone folks recommend for my phone. With it, the phone is supposed to be correctly calibrated. Even if it's correct, though, how do I know if the measured light level is right for my plants? Do I trust the charts? I don't think that's good enough. That's how reading the plants is involved. I'm not going to follow the chart if I can see light stress on the plants. There are too many other factors involved to follow the charts alone.

Charts are jump off points.

 

[LoveGrowingIt]

Charts are jump off points.

Oh, I know. That was the point of my post.

 

[Captspaulding]

I'd leave it at 40% for a while longer. A picture would help.

Recognizing the signs of light stress (or burn) can be more useful than a light meter. Watch for the signs after increasing the power, and if you see them, reduce the power or increase the height of the light.

FACTS
YES
Don’t use a Doohickey
It’s never better than the human eye stress factors all have precursor tendencies, especially when it comes to light your plant going from dark green to light green? Are your leaf edges curling up towards the light? leaves bowing down to hide out of the way? are we wilted from lack of feeding and mistaking it for light stress? Or the very, very farthest points of the leaf tips starting to brown all the way around the leaf starting at the farthest point? These are all things that you can look for that application or a light meter cannot. No number coming out of a machine will ever be able to stop your plant from being affected by these factors. can’t agree with this statement more

 

[PooToe]

FACTS
YES
Don’t use a Doohickey
It’s never better than the human eye stress factors all have precursor tendencies, especially when it comes to light your plant going from dark green to light green? Are your leaf edges curling up towards the light? leaves bowing down to hide out of the way? are we wilted from lack of feeding and mistaking it for light stress? Or the very, very farthest points of the leaf tips starting to brown all the way around the leaf starting at the farthest point? These are all things that you can look for that application or a light meter cannot. No number coming out of a machine will ever be able to stop your plant from being affected by these factors. can’t agree with this statement more

While I agree I also think they're useful for setting your light output at different stages of growth if you've already run the cultivar and know its light limits.

 

[costanza]

AFAIK, the Photone app works well if it's calibrated. I've been using a clip-on "Diffuser & Cosine Corrector" that the Photone folks recommend for my phone. With it, the phone is supposed to be correctly calibrated. Even if it's correct, though, how do I know if the measured light level is right for my plants? Do I trust the charts? I don't think that's good enough. That's how reading the plants is involved. I'm not going to follow the chart if I can see light stress on the plants. There are too many other factors involved to follow the charts alone.

I had issues with that app until I bought that 25 dollar cosine corrector.