Lighting question

eliasson420

Member
what would be more beneficial for a 12/12 from seed grow. keep in mind the seedlings and maturing females are in the same space. baseline is the 70w hps which is 2000k. which would be better to add? (2x26w 6500k or 1x68w 2700k) i can only choose one because of the added heat. obviously the big 68 watter is brighter, but i have a hunch that the 6500k bulbs would give more usable light per watt. my other question, as ive only recently began using the hps, is 6 inches from the canopy too close? just wondering if plants can be damaged by light intensity? temps are 77-81 degrees at canopy with good air movement.
 

calicat

Well-Known Member
Use the back of your hand to test the intensity of your light source. If your hand tolerates it at your distance the canopy will as well. Yes plants can be damaged by light. You are in optimal range with your existing temperatures.
 

Agito

Well-Known Member
at least veg for a week before going 12/12 as plants wont flower anyway until they have a bit of progress on them

70w hps are poor they dont get efficient until higher wattages so it wont matter that much
 

eliasson420

Member
anybody care to answer the question lol? 2x26w 6500k or 1x68w 2700k. my area is 1 sq foot, my 70w hps is plenty by itself, but i want to add another specturm to the mix. i have all these bulbs i might as well use them if they will help. i have been growing 12/12 with cfls for 6 harvests, i have a perpetual harvest system that works for me. my question is geared toward which of these two setuos will give me the best quality bud. does blue light benefit flowering in any way? also i leave my seedlings under a lamp with 24/0 light for the first 3 or 4 days, not intense light just enough to know its daytime. when i switch straight to 12/12 it shocks the hell out of them for like 2 days, then they go apeshit. even straight sativas grow bushy for me.
 

eliasson420

Member
first guy answered one part of my question, thank you bro. second guy....are you just scouring the web critiquing peoples grows? put a 70w hps in a 1 sq ft cab and see what happens. ill tell you one thing the result isnt "poor". my post didnt ask any questions about whether the 70w was sufficient and i definetly didnt ask anyones opinion about 12/12 from seed. just saying.
 

Agito

Well-Known Member
dont be a bell i was trying to be helpful i would not use a hps in such a small space
Also you mentioned 12/12 from seed in first post saying 1 week veg plants should finish in the same time but yield more as you cut stress
To answer your Q 6500k is the cool spectrum hps has less of.
The point i was trying to make your cfls may be putting out more par watts than your hps so going 100%cfl may be an idea and you should look into it
I scour the net to improve people grows and helped thousands over my 16 years thank you very much its you that lacks answers
 

eliasson420

Member
haha the only answer i lack is the same damn question nobody seems to want to answer. i apologize, but when you seek answers and all anybody says is "oh youre doing that wrong"...its a bit annoying plus im out of weed. just for the record cfls put out lots of visible light, but a lot of it is green light thats reflected off the plant. i think i heard only 10% of the light is used by the plant. so...out of the equipment i currently have, which would be better? 70w hps with 2X26w 6500k cfls or 70w hps with 1x68w 2700k cfl. if somebody tangents on something i havent asked about im abandoning this damn thread.
 

Agito

Well-Known Member
ive already told you the 6500k on my last post. hps is orange lacks blues . 6500k is blue
cfl spectrum is actually better than hps its just that the hps has a far higher lumen par watt making it better with more par watts than cfl in the higher wattages
your lighting knowlege is way off with the green thing


View attachment 2440097
 

jayelle

Member
yea deff the 6500k would give u more of that "different spectrum" your looking for, the 2700k is just a bit diff than your hps.
 

eliasson420

Member
even if the blue spectrum doesnt give me visible results, i like the way it makes the cab look. can anybody shed some light on these graphs? i just dont get what these bars mean that go up higher than the rest of the line. they are at, roughly, 400, 440, 550, and 600nm. considering none of these points are congruent to peak levels of photosynthesis, i dont know wtf they mean. first is 2700k second is 6500.
View attachment 2440166View attachment 2440167
 

Agito

Well-Known Member
cfls and hps are full spectrum but hps has higher % peaks in orange probs your pic 1. they dont just contain 1 color like leds

blue light wave is very photo active and does give you visible results

the pic i gave you shows the spectrum that plants use (the green part on the graph above^) as you see they use blue very well

heres another graph on how its used by plants

LightInLakesChlorophyllChart.gif
your answer is still 6500k
 

eliasson420

Member
right on bro. it was crazy, i open the cab after a full 12/12 cycle. i shit u not, the leaves got bigger man... i thinkin of gettin another pc fan and just using them all lol. ill post pics when im done. i live in a prohibitionist state....so im not postin shit til its out of the house :-) later bro thnks
 
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