New build LED lighting

[guccisimo85]

I think I am going to replace my existing all in one grow setup with a set of metal shelves so I can customized the lighting. Pics below of what I have in mind

I’m thinking a 48” x 24” x 72” metal shelving unit. Might leave a 12” shelf at the bottom for storage, which would give me two 30” shelves for plants.

Do you think these LED fixtures would be a good choice? It’s a Spider Farmer SF 1000 fixture. They are adjustable (both wattage & height), so I could dial them in. I grow mostly high light demanding species.

Thoughts or suggestions?

Robot Check

[estación seca]

I don't know that light. Go to a hydroponics shop and ask what the marijuana growers might use if they existed.

[Keysguy]

if they existed

I just did almost the same thing but I went with the lights from Orchid Hobbyist....
Orchid Hobbyist

I like the spectrum they cover and they're actually a little cheaper. So far though that's all I can offer as they are back-ordered for another couple weeks. Fortunately I had an old sodium/magnesium (whateverium) 2 bulb monster thing with a 50# ballast left over from my old greenhouse. Glad I saved it as it still works and should get me through till the new bulbs arrive. I can tell when it's on because I can hear my electric meter spinning out of control.

Don't forget humidity trays, fans, light meter, etc.

[Clawhammer]

I think that light will be too powerful, you may be able to get away with 2 levels on the shelf but definitely not 3.

These lights work wonderfully with wire racks and two of them fit perfectly on a shelf, spreading out the light. It is less expensive too.

https://www.amazon.com/Relassy-300W-...5-4be35d7258cc

[Ray]

I agree - the PPF is entirely too high considering the maximum shelf-to-leaves distance.

Plants grown under artificial lights should get a PPF of 50-60% of the maximum level they would receive in natural sunlight. A plant whose recommended sunlight max is 5000 fc would need about 2500 fc of continuous artificial light, and if we divide that by 5, that’s about 500 micromoles/square meter - and that’s the sum for the whole day.

So if that was under the center of that lamp, that would be the equivalent of about 30 minutes exposure.

[DirtyCoconuts]

okay, so i have a really stupid person question. is there is simple way to calculate the power of the lamp at a given distance for every light source?

i know that is poorly worded but i am trying to figure out the power of a lamp i have at a given distance to compare it to another at a different distance.

i am building into this question the fact that these LED panels all have different bulbs in different places so if the plant is like 8" away from a panel that is 8" long is it getting the full range of the panel or just the section over it?

i guess my confusion comes from the fact that the LEDs are working as a group but since their light diffuses faster than other sources, is there a minimium distance the plant has to be away from the fixture before it become "full spectrum"?





so, as applies to the OP question, would there be one shelf getting the ideal light while one too high would be both too intense and not the full range?

[guccisimo85]

That is actually a really good question. I wonder if I = S / 4πr^2 holds up for all different wavelengths of light and can be applied to adjust manufacturer’s PPFD values to further distances. Overall, I think it’s most actually calculated empirically using a light meter, but I get that that’s not practical unless you have an expensive light meter (and take the time to do it).

I ended up going with these lights:

http://www.amazon.ca/gp/aw/d/B079C2Y...?ie=UTF8&psc=1

I had ordered a set for my vandas and I am impressed so far, so I will keep things consistent for the rest of my setup. I must say the COB lenses do an awesome job of focusing the light. I have them hung 7-8ft up in the air (about 24” above my hanging vandas) and I have been able to place plants underneath the vandas (so that’s a good 6ft below the lights) and I am getting 150 PPFD that far down! They are marketed as having very good canopy penetration and now I see why Up at the level of the vandas I am measuring 350-400 PPFD.

I will probably take the lenses off for my metal grow racks to get better coverage (and I don’t need the light to be that focused). They also have IR and UV. They produce very “clean” light which is also nice for actually getting to sit and enjoy the plants

Originally Posted by DirtyCoconuts

okay, so i have a really stupid person question. is there is simple way to calculate the power of the lamp at a given distance for every light source?

i know that is poorly worded but i am trying to figure out the power of a lamp i have at a given distance to compare it to another at a different distance.

i am building into this question the fact that these LED panels all have different bulbs in different places so if the plant is like 8" away from a panel that is 8" long is it getting the full range of the panel or just the section over it?

i guess my confusion comes from the fact that the LEDs are working as a group but since their light diffuses faster than other sources, is there a minimium distance the plant has to be away from the fixture before it become "full spectrum"?





so, as applies to the OP question, would there be one shelf getting the ideal light while one too high would be both too intense and not the full range?

[Clawhammer]

Originally Posted by DirtyCoconuts

okay, so i have a really stupid person question. is there is simple way to calculate the power of the lamp at a given distance for every light source?

i know that is poorly worded but i am trying to figure out the power of a lamp i have at a given distance to compare it to another at a different distance.

i am building into this question the fact that these LED panels all have different bulbs in different places so if the plant is like 8" away from a panel that is 8" long is it getting the full range of the panel or just the section over it?

i guess my confusion comes from the fact that the LEDs are working as a group but since their light diffuses faster than other sources, is there a minimium distance the plant has to be away from the fixture before it become "full spectrum"?





so, as applies to the OP question, would there be one shelf getting the ideal light while one too high would be both too intense and not the full range?

The last graphic posted by the OP is the key to your question. It gives the height, footprint of the light, and the PPE

I like larger panels because the more spread out the light source the more direct the light / less shadows from other plants. All of that is considered in the PPE graphic.

I have lights on each shelf, pic attached

[Clawhammer]

That light is similar intensity to the original one. The values are from 24" height vs the original light @ 12"

Originally Posted by guccisimo85

That is actually a really good question. I wonder if I = S / 4πr^2 holds up for all different wavelengths of light and can be applied to adjust manufacturer’s PPFD values to further distances. Overall, I think it’s most actually calculated empirically using a light meter, but I get that that’s not practical unless you have an expensive light meter (and take the time to do it).

I ended up going with these lights:

Robot Check

I had ordered a set for my vandas and I am impressed so far, so I will keep things consistent for the rest of my setup. I must say the COB lenses do an awesome job of focusing the light. I have them hung 7-8ft up in the air (about 24” above my hanging vandas) and I have been able to place plants underneath the vandas (so that’s a good 6ft below the lights) and I am getting 150 PPFD that far down! They are marketed as having very good canopy penetration and now I see why Up at the level of the vandas I am measuring 350-400 PPFD.

I will probably take the lenses off for my metal grow racks to get better coverage (and I don’t need the light to be that focused). They also have IR and UV. They produce very “clean” light which is also nice for actually getting to sit and enjoy the plants

[guccisimo85]

Yes, good point. I think that while that may be true in theory, I am getting 400 PPFD dead centre at 18” with these ones. I‘m learning to kind of take the manufacturer specs with a grain of salt. I’m not running it in a grow tent either so I think I lose a fair amount of the light. I guess ultimately I would rather go with something I have experience with and have seen in person.

It’s so hard to tell when you are buying lights online. I actually thought these were way smaller and was shocked when I opened the box and realized their size I’m just lucky they worked for their original purpose; I spent an hour reconfiguring the hanging mechanism while inside the grow room at 85F and 75% humidity

Originally Posted by Clawhammer

That light is similar intensity to the original one. The values are from 24" height vs the original light @ 12"