InTheShed Grows Inside & Out: Jump In Any Time

[Homer Simpson]

OK, technically you're correct but for our purposes, your really not!

We've been using the term "intensity" to describe the "power" of the lights hitting the plants. Really, intensity measures the amount of energy photons hitting the plants in a given amount of time. In the LED world, this is the PPFD (Photosynthetic Photo Flux Density). However, the wavelength (PAR) determines the amount of energy per photon.

I understand we're getting way deeper than you originally intended. My point is simply that the spectrum effects the PPFD and inverse square law is only accurate when looking at the same light at two distances and does not necessarily apply to two different lights.

I agree with all your definitions but I still have to come to the conclusion that we are on different wavelengths, LOL. Again I don't see the relevance of bringing up different spectrums because my query was only about my one light.

Anyway, since the inverse square law only applies to single point sources my whole question has been rendered moot but I appreciate your attempt to help and your intellect.

 

[Homer Simpson]

And since most LEDs illuminate over a 120 angle, there’s a lot of overlap from multiple LEDs.

It gets confusing, but it’s real world.

Agreed, lol. I do learn a lot out here and specifically today that I think it is worth raising my lights because it won't take as much energy as I thought for the same illumination higher up than when I started this discussion.

 

[FelipeBlu]

Better penetration is one of the benefits of LED arrays over other light sources, like HPS.

 

[Mr. Krip]

I agree with all your definitions but I still have to come to the conclusion that we are on different wavelengths, LOL. Again I don't see the relevance of bringing up different spectrums because my query was only about my one light.

Agreed!

In your original post, it wasn't clear to me that you were talking about the same light. You did say you were thinking about increasing the distance but you also said:

180 W at 2 feet I would need 405 Watts at 3 feet opposed to 2 feet distance from my canopy

So, I assumed if you were going from 180w to 405w it would be with a different light. Not many of us keeping our 400w lights dialed down to 180w.

You did clarify that, though, in a later post, but I had already let the cat out of the bag!

 

[Homer Simpson]

Agreed!

In your original post, it wasn't clear to me that you were talking about the same light. You did say you were thinking about increasing the distance but you also said:



So, I assumed if you were going from 180w to 405w it would be with a different light. Not many of us keeping our 400w lights dialed down to 180w.

You did clarify that, though, in a later post, but I had already let the cat out of the bag!

Thank you for the clarification; now it makes sense why you were bringing up different wavelengths.

I am actually keeping my 650 W MegaLight at 180 W. Obviously, no one in their right mind would buy such a huge light and underutilize it so severely but being fortunate to be gifted it with my, Journal of the Month, thank you very much, it didn't cost me anything.

NextLight recommends getting no closer than 2 feet at 650 W but when I tried going from 180 W to 250W at 2' with my latest plant I thought it was going to die. Strange but my plants are happy with 180 W in a 3' x 3' area which is only 20 W per square foot amazingly. I'm happy they thrive with so little energy as it reflects well on my electric bill. Here is my Gorilla Glue that has been in flower mode for about a week and a bit in a 10-gallon pot with a trunk over an inch in diameter.

 

[FelipeBlu]

Nice photo illustrating the concept of penetration! I would consider removing anything in the dark.

 

[Homer Simpson]

Nice photo illustrating the concept of penetration! I would consider removing anything in the dark.

I have reflectors but I just removed them to take the pic.

 

[FelipeBlu]

Nice photo! Could be on a magazine cover.

 

[Graytail]

We have members who have used their expensive and accurate PAR meters to measure actual dropoff from distance. It turns out, because it isn't a pinpoint source, that at twice the distance, you only need roughly 2 1/2 times the power/umols. It depends on the source type. Widely dispersed lighting will require less and single source will require more.

So a 50% increase in headroom should only require double or less, and the upside is that you'll also get a deeper canopy because of the higher power.

 

[Homer Simpson]

We have members who have used their ezpensive and accurate PAR meters to measure actual dropoff from distance. It turns out, because it isn't a pinpoint source, that at twice the distance, you only need roughly 2 1/2 times the power/umols. It depends on the source type. Widely dispersed lighting will require less and single source will require more.

So a 50% increase in headroom should only require double or less, and the upside is that you'll also get a deeper canopy becsuse of the higher power.

Thanks for the rule of thumb Graytail. That was helpful and it was cool seeing my pinpoint theory wasn't nuts. I would think a pinpoint source at twice the distance would be a factor of 4 so only 2 1/2 is a big difference. Sounds much more worth it.

 

[Grand Daddy Black]

Graytail and Homer, it seems you have reached that special place! I appreciated the discussion. If it taught me nothing else, it taught me I have a lot to learn!

 

[CraZysWeeD]

inverse square law, which while I can't explain it...

Wounder if Schrödinger's law is useful with this as well...?

 

[CraZysWeeD]

Here is my Gorilla Glue

Nice photo! Could be on a magazine cover.

I agree with Felipe, one of the most beautiful pics of a plant I ever seen here before buds develop. In my opinion they are most beautiful in this stage, fruits signal the plant is getting ready to end its life and cycle...

Love it man!

 

[Homer Simpson]

Graytail and Homer, it seems you have reached that special place! I appreciated the discussion. If it taught me nothing else, it taught me I have a lot to learn!

Yes, GDB, me too. I think my biggest strength is I listen to those who know more than me which is just about everyone.

 

[Homer Simpson]

I agree with Felipe, one of the most beautiful pics of a plant I ever seen here before buds develop. In my opinion they are most beautiful in this stage, fruits signal the plant is getting ready to end its life and cycle...

Love it man!

Thanks, man!

 

[Homer Simpson]

Sorry for stealing your thread, Shed. It was not my intention.

 

[Heavenly Hybrid]

Well Homer, I don’t know anything about lights, but I do know that’s a beautiful photo. If it were me, I’d be entering that puppy in the phOTM contest!

 

[Virgin Ground]

Morning Sheddie.

 

[Homer Simpson]

Well Homer, I don’t know anything about lights, but I do know that’s a beautiful photo. If it were me, I’d be entering that puppy in the phOTM contest!

Awww... shucks. Thanks, Heavenly Hybrid, I just might. Thank you.

 

[oldsmokey]

I agree Homer beautiful plant you should enter it.