dandyrandy
Well-Known Member
I would love to try de. But with stealth I have to be very quiet and not much air movement for cooling. Visitors
recommended ppfd range?
- Thread starter sunny747
- Start date
MeGaKiLlErMaN
Well-Known Member
Yeah less better anyways lol DE is great if you want to throw money out the window lol. Or if you want the heat to reduce your gas bill for some reason
giantsfan24
Well-Known Member
I found one on Amazon for about $40 and added it to my shopping list. In is space with limited height, knowing what you're putting out at what distance could be very helpful in addition to giving the grower more flexibility. Great suggestions!
Simple Clean
Active Member
If you look at PAR readings on most LED grow lamps, the PAR readings diminish quickly the farther from the center the measurement. Has anyone tracked yield by plant as positioned in one grow space? Logically you would assume, the higher the PAR reading the more yield. Do the yield values correlate consistently to their associated PAR? Do the hot-spot plants dominate in yield values and finish prior to the outside plants?
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nevergoodenuf
Well-Known Member
@Simple Clean some of my better tops aren't in the middle, but on the edges. I only have a lux meter, but checked 200,000 lux = 975 ppf
with the meter I use. So, directly under the COB, I am just under 1000 ppf at each of the 10 COBs.
with the meter I use. So, directly under the COB, I am just under 1000 ppf at each of the 10 COBs.
Bluecollarbudz90
Member
Not necessarily and ppfd is to general that's only good for a par map and setting readings with a quantum sensor. The correct term here would be ppf or umols/j efficiency. Co2 could easily make a better Gpw because the plants can handle more intense light up to 2000 ppf if co2 is in the 12 to 1500 range google Bruce bugsby professor of horticulture science on youtube. This was the dumbest most generalized statement on this board misleading as fuck. I wont flame you to bad considering this thread is old and horticulture lighting has came leaps and bounds in the led world since then but still making a statement saying more ppfd is less gpw is nothing less then ignorance
Rocket Soul
Well-Known Member
Lol. Harsh words from someone who clearly dont understand the difference between PPF and PPFD.
cobshopgrow
Well-Known Member
lower ppfd = higher gpw
bruce isnt saying other in his videos if you check the curves he is drawing, theyre not linear.
give em 2000 ppfd and you wont have doubble the yield then giving them 1000 ppfd
while you need more then doubble the watts to reach 2000 ppfd compared to 1000 ppfd.
bruce isnt saying other in his videos if you check the curves he is drawing, theyre not linear.
give em 2000 ppfd and you wont have doubble the yield then giving them 1000 ppfd
while you need more then doubble the watts to reach 2000 ppfd compared to 1000 ppfd.
Bluecollarbudz90
Member
Really dude listen photosynthetic photon flux is measured as a whole photosynthetic photon flux density is measured in a particular spot at a particular distance away from the light source hense the added word thier density is how dense is the photo activity going on in that one particular spot in lamens terms and I clearly said that backwards in my last post I apologize
end_of_the_tunnel
Well-Known Member
The three P's.
PPE = efficiency (of lamp/fixture).
PPF = output (of lamp/fixture).
PPFD = quantity measured at a fixed point (usually at upper canopy level).
CobKits
Well-Known Member
the curve is not linear as ppfd increases. higher GPWs are certainly found at the lower PPFD ranges. higher PPFD growing is diminishing returns, always has been, and any 'leaps and bounds' in horticultural lighting isnt changing this fundamental rule. Look at this rule of thumb i posted in context of the other one i post all the time. They are both fundamental and true and not mutually exclusive.
all other things being equal
lower ppfd = higher gpw
lower ppfd = lower g/sf
Bluecollarbudz90
Member
Co2 makes 2000 ppfd plus possible according to studies going on now where exactly the diminishing returns exist are above where led can produce without bleaching because of how close you have to be with em. If.im running 1700 ppm of co2 in a room where my canopy temp is 82 degrees exactly with double ended lights above them BLASTING DOWN AN AVERAGR PPF OF 2000 I am going to SHIT DIAHREEAH ALL.OVER ANY COB GROW PERIOD. THE ONLY THING LED IS BETTER AT IS SAVING MONEY AND HEAT BUT IF YOUR PUSHING 1.5 GPW OFF 1000 DES IN A CONTROLLED ROOM LIKE THE ONE SAID ABOVE THIERS NO WAY WHAT YOUR SAYING IS TRUE HIGHER PPFD DOES NOT STAND TRUE ANYWHERE UNDER 2000 PPFD NOWHERE IS THAT TRUE IM.GONNA GET MORE GPW AT 1000 PPFD THEN I WOULD AT 600 PPFD FLAT THE FUCK OUT YOUR A SALES REP FUCK
end_of_the_tunnel
Well-Known Member
Photosynthetic response of Cannabis sativa L. to variations in photosynthetic photon flux densities, temperature and CO2 conditions
Effect of different photosynthetic photon flux densities (0, 500, 1000, 1500 and 2000 μmol m[−2] s[−1] ), temperatures (20, 25, 30, 35 and 40 °C) and CO[2] concentrations (250, 350, 450, 550, 650 and 750 μmol mol[−1] ...
Rocket Soul
Well-Known Member
Rude and hyperbole.
1.5 is really good with hps, even with DE. But even so you need around 1000w per meter to get those light levels, 2000ppfd. Youre saying that you can get a 1500g per meter with 1000w DE but its impossible to do 500g per meter with a 240w full efficiency led setup. Thats a bit rich and maybe you can show it off in a thread but until then i call bullshit. Cobby is generally right ("all other things being equal") allthough a bit sloppy in his statement. Cobbys original statement is a bit off; ppfd and grams per watt dont have a direct relation since you can get to 600ppfd using more or less wattage.
Of course 240w will not beat 1000w in g/m2. But if you wanna say more g/w at 1000w per meter then why dont you just prove your numbers? Why dont you show us your 4 pounds a light with 140g per square foot.
Bluecollarbudz90
Member
That's not running a single light that would be in a pattern formation work over lap accounted for I haven't done it I'm currently pulling about 1 to 1.2 gram a watt in a cmh/hps over lap perpetual in coco recirculating flood and drain and other half dtw . I'm referring to what I know and have seen from commercial over lap. No one in thier right mind would expect 4 a light but every 5 by 5 with over lap and full canopy with everything dialed in you'll get damn close with the right strain and genetics at play I'm not playing a game of "what's your variable" thiers to long of a list to get into that. And noone is comparing to a 240. You also dont get shit for over lap with cobs either and the checker board over lap would be the straw that broke the camel's back to be able to push those numbers overlap and intensity equals more GPw all things more intense. Also I have a 240 watt carson high yield led its trash i use it for supplementing my hps. If you wanna spend hours training the plant to get the canopy right to maybe attain a better gpw with leds be my guest but the extra power bill and bulb changing costs dont mean shit when your spending 20 to 30 hours less a week per 500 sq foot of grow. Hid more power more penetration led better gpw if you spend hours training plants and have an extensive knowledge of nutrients and growing and oh TIME if you dont wanna spend hours training plants like mr miyagis faget ass dont use leds
Bluecollarbudz90
Member
That studies old news dude 11 years old lmfao YouTube Bruce bugsby and get your notepad out professor of horticulture sciencePhotosynthetic response of Cannabis sativa L. to variations in photosynthetic photon flux densities, temperature and CO2 conditions
Effect of different photosynthetic photon flux densities (0, 500, 1000, 1500 and 2000 μmol m[−2] s[−1] ), temperatures (20, 25, 30, 35 and 40 °C) and CO[2] concentrations (250, 350, 450, 550, 650 and 750 μmol mol[−1] ...www.ncbi.nlm.nih.gov
Bluecollarbudz90
Member
Nanolux 630 cmh Phillip's 930 agros
Super hps 1000 xxl ac
315 valiant cmh Phillip's 930.agro
600 watt super hps ac hood
8 inch 745 cfm
4 osc fans
Active air
Temp mid 70s
Advanced connie base
Cannazyme /semsizyme
Nirvana
Photo synthesis plus
Fox farm PK trio
Flush with flawless or water and enzymes
Perpetuals 3 groups
7 gallon 5 gallon cocos some.fabric some not back row is a home made 4 mod pot flood and drain on split timers 30 min full saturation 3 times a day everything is fully dialed ph nutes etc.. I started growing and doing this last june and decided to spend the entire year self education and picking master growers minds I have 12 harvests already under my belt since june 2k19 and I wont post any pics of my first grows dont ask lmfao.
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Rocket Soul
Well-Known Member
So
All my maths are fine: if you want 2000ppfd average across cannopy EVENLY you need around a 1000w of DE per meter (DE have a ppf of around 1900 at 1000w, meaning you need about 1000w/m to get to 2000ppfd unless you use magic lights).
You said you can beat a the grams per watt of 600ppfd cannopy (which can be achieved reliably by 240w of led).
So extrapolating what you claim: show us your grow (or anyone others) 1500g per meter. If you can ill happily go and look for some grower doing 400ish grams with 240w over a meter.
Noone is doubting that youve grown some decent weed. However digging up an old thread to call people out on something you cant actually understand the underpinning maths is bullshit. Especially since youre an admitted growbro science dude.
Just show us 1500g per meter with 1000w De. Thats what you claimed lets see it.
So... Winge winge and crickets? Show it if you got it or admit that youre just punking.
All my maths are fine: if you want 2000ppfd average across cannopy EVENLY you need around a 1000w of DE per meter (DE have a ppf of around 1900 at 1000w, meaning you need about 1000w/m to get to 2000ppfd unless you use magic lights).
You said you can beat a the grams per watt of 600ppfd cannopy (which can be achieved reliably by 240w of led).
So extrapolating what you claim: show us your grow (or anyone others) 1500g per meter. If you can ill happily go and look for some grower doing 400ish grams with 240w over a meter.
Noone is doubting that youve grown some decent weed. However digging up an old thread to call people out on something you cant actually understand the underpinning maths is bullshit. Especially since youre an admitted growbro science dude.
Just show us 1500g per meter with 1000w De. Thats what you claimed lets see it.
end_of_the_tunnel
Well-Known Member
I got a feeling Bugby is going to reaffirm a lot of what those University of Mississippi folk (and others) have written. Dude.
cobshopgrow
Well-Known Member
oh man... bruce is so clear on this topic and some still get it wrong.
he hardly can be clearer, rocket and end of tunnel are a 100%.
you just need to click and watch.
you get more yield per watt at 600PPFD, then 2000, yes.
you get more overall yield using 2000, thats what youre arguing with, but thats just not G per W.
diminishing return is the term
just click wathc understand, if you dont understand, idk.... i am lost.
he hardly can be clearer, rocket and end of tunnel are a 100%.
you just need to click and watch.
you get more overall yield using 2000, thats what youre arguing with, but thats just not G per W.
just click wathc understand, if you dont understand, idk.... i am lost.