Light Distance - Factory recommendation

  • Thread starter Tazzmania
  • Start date
  • Tagged users None
Tazzmania

Tazzmania

18
3
i have Mars hydro FC-E3000 LED light and Marsh Hydro recommends 12" distance @%100 but im not sure if i should follow, what do you guys think?

Stage: Week 6 of flowering

Light distance   factory recommendation

Light distance   factory recommendation 2
 
D

Drasik

48
18
i have Mars hydro FC-E3000 LED light and Marsh Hydro recommends 12" distance @%100 but im not sure if i should follow, what do you guys think?

Stage: Week 6 of flowering

View attachment 1221033
View attachment 1221034
It would be great if everyone had a PAR meter. MARS hydro is not a cannabis company and often their suggestions are not the greatest. I assume they are telling you to increase CO2 at higher PPFD to keep the plant metabolism going in line with adding light. When your vegging 600 ppfd is great but the other issue you have is if you're following their charts they usually exaggerate their PPFD numbers. having a PAR meter actually helps to know how much photons are actually available. What is the rated efficiency and PPF of the light. If it's DLC listed go to the DLC website and get that info.
 
Tazzmania

Tazzmania

18
3
i have 4 plants 4x4 and they are flowering, week 6. i found the photon app thanks to you, will share the ppfd @12 inches
 
_VLAD_

_VLAD_

417
93
Id go 18" and see how they like it. An inch here or there isnt going to dramatically screw up your yield.
 
D

Drasik

48
18
Id go 18" and see how they like it. An inch here or there isnt going to dramatically screw up your yield.
If you look at the DLC specs he posted there, it is just under 800 PPF available from the light source. Depending on the coverage area from the light source and these numbers you usually would generally get about 580 PPFD at 12" and probably 320 PPFD at around 2 feet. At the beginning of vegging a good ratio for cannabis is about 500-600 PPFD at top of canopy. Now all lighting specs are put together differently and different fixtures have different methodologies of delivery so sometimes using numbers is not the best way to assess. PAR meters give you the real availability of photons on your plants. On a light with this output you might get a little me more coverage area at 18" but its only 4 plants so I'd suggest keeping it at 12" and playing around with dimming as adjustments. I don't know what the dimensions are for this light so don't know coverage area.
 
PipeCarver

PipeCarver

Supporter
5,643
313
i have Mars hydro FC-E3000 LED light and Marsh Hydro recommends 12" distance @%100 but im not sure if i should follow, what do you guys think?

Stage: Week 6 of flowering

View attachment 1221033
View attachment 1221034
I bought a cheap led light meter to go by. with that you can gauge the lux #s I can then use those #'s to turn up or down my light...its working so far...in veg they can handle 25,000 lux but I cooked a my leaves in flower with it too high 55,000 and being under nourished. I'm now flowering at 35,000 1 week into flower with my SE3000 I'll bump it up as I go but I'll also increase the feed a bit as I do....GL...Canadian price here for mine
1645984730628
 
Tazzmania

Tazzmania

18
3
ok, i used photon app for measurement. lowered my light down to 18 inches and dimmed little bit @%80-90,
Lux readings are minimum 2000 lux and max 42000 lux (center) should i go down to 30000 lux?
 
PipeCarver

PipeCarver

Supporter
5,643
313
ok, i used photon app for measurement. lowered my light down to 18 inches and dimmed little bit @%80-90,
Lux readings are minimum 2000 lux and max 42000 lux (center) should i go down to 30000 lux?
Have you been at this same number for a few days? how are your leaves looking...any fading or color change, burnt tips, curling leaves foxtails from being to close to the light?...they can handle far more but your environment and food needs to be on par with your numbers....I'm an amateur with the leds but your plants will tell you if they're happy or sad.....My plants finished great even under the higher power with fried leaves...if your leaves look good carry on as you are if not dial back... pics are a must if you want more help...
 
D

Drasik

48
18
I bought a cheap led light meter to go by. with that you can gauge the lux #s I can then use those #'s to turn up or down my light...its working so far...in veg they can handle 25,000 lux but I cooked a my leaves in flower with it too high 55,000 and being under nourished. I'm now flowering at 35,000 1 week into flower with my SE3000 I'll bump it up as I go but I'll also increase the feed a bit as I do....GL...Canadian price here for mine
View attachment 1221310
Hey guys, in the past we used lux or lumen meters to try and gauge how effective our lighting could be. But for cultivation its really not about lux/lumens, the measurement we really care about it photosynthetically active radiation(PAR). Its the amount of energy available to drive photosynthesis in a plant. All lux/lumens tell us is how bright a light source can be not how much energy we have. So when you guys are using these lumen app or meters they don't tell u much about the real driver behind the light you need. If you don't have a PAR meter to measure that, then using your manufacturers recommendations is your best bet. The one major issue in the market that we've observed is that manufactures often exaggerated their values by a lot in their marketing material. For example, your SE3000, states that at about 10" you can achieve a photosynthetic photon flux density (PPFD) of about 1100 umols/m2/s however if you go to their DLC listings( Design lights consortium - industry 3rd party certification) the PPF (photosynthetic photon flux) is only at about 800 so there is no way it could get that high if the source is lower than that. So you have to do your research if you don't have a PAR meter. I'm gonna try and post some articles on some lighting information in the learning section but you can check out some info on our Instagram and website Green Amber Canada
 
D

Drasik

48
18
Have you been at this same number for a few days? how are your leaves looking...any fading or color change, burnt tips, curling leaves foxtails from being to close to the light?...they can handle far more but your environment and food needs to be on par with your numbers....I'm an amateur with the leds but your plants will tell you if they're happy or sad.....My plants finished great even under the higher power with fried leaves...if your leaves look good carry on as you are if not dial back... pics are a must if you want more help...
Sometimes its not the light itself that causes the issue. When we first started testing our lights 2 years ago we noticed VPD issues. There sometimes is a learning curve with new equipment.
 
PipeCarver

PipeCarver

Supporter
5,643
313
Sometimes its not the light itself that causes the issue. When we first started testing our lights 2 years ago we noticed VPD issues. There sometimes is a learning curve with new equipment.
Hey, just looking at your 1 sentence paragraph. I won't read that stuff. You need to put in some breaks. Space it out a bit to allow for easier reading.........1 sentence stuff with no breaks gets ignored by me......I'm old and I have a hard time reading endless text......just saying.....
 
Top Bottom