6500 vs 5700 vs 5000K for veg
- Thread starter BOBBY_G
- Start date
nope. the narrow blue peak at 450nm is responsible for all of the blue wavelengths (as supraspl pointed out), so even if the CCT is the same sunlight has a much wider spread of blues going all the way from actinic blue through cyan, as well as UVB and UVA wavelengths.
EfficientWatt
Well-Known Member
CCT ==/== SPECTRUM for godsake
Enough of this sunlight BS. Reproducing sunlight is HIGHLY INEFFICIENT.
Only reason sunlight works (in part) well, is that sunlight is free ... A 56% efficient cob with mid day spectrum would have LOW PPF/W
Well over 50% of the sun output isn't even in the PAR range ... so a 56% efficient 'sunlight cob' would have something like 25 PAR W for 100W used at best, probably much less actually ...
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2ANONYMOUS
Well-Known Member
Well i am going with 6500k and 3500 k mixed i think that will indeed be overall best when comparing it to actual sun Bob one must remember plants can only utiilize 10 percent of mid day light so why on god earth would a person want to run light only mid day ??
i mean you could be loosing out on some certain plan cues from early morning Blue that triggers proteins from with in the nuclear Gene
Everyone is tryin to be Dr Frankenstein when its really simple 3000 k and 6000 k well rounded for all stages end of story
PS i waited on cutter to get back to me on prices for 6500 and 3500k etc still noting and over a week so i think i will go and talk to Jerry on prices also waiting on another cree supplier for his cost so purchasing is soon
2ANONYMOUS
Well-Known Member
lol in your eyes its not efficient by what standard ??CCT ==/== SPECTRUM for godsake
Enough of this sunlight BS. Reproducing sunlight is HIGHLY INEFFICIENT.
Only reason sunlight works (in part) well, is that sunlight is free ... A 56% efficient cob with mid day spectrum would have LOW PPF/W
Well over 50% of the sun output isn't even in the PAR range ... so a 56% efficient 'sunlight cob' would have something like 25 PAR W for 100W used at best, probably much less actually ...
If you regard purely the thermal efficiency, yes, it will radiate close to 100% of the energy from nuclear reactions outwards in the form of electromagnetic radiation, ions, nucleons, and neutrinos which will heat up or ionize something else in some way.
A more interesting question is whether it is efficient at maximizing binding energy towards the iron/nickel elemental distributions towards the end of its life span. Take the sun; it is predicted that most nuclei would fuse into carbon at the end of its lifetime, but not further into "shell-burning" oxygen, neon, potassium, titanium, chromium, or iron as do most supergiants.
Then the ultimate question is mass-energy equivalence; the sun loses several million tons of matter per second as a result of this, but ultimately that represents a tiny fraction of its overall mass even by the end of its lifetime.
EfficientWatt
Well-Known Member
LOL back to you.
I said a cob "repoducing sunlight" would be highly inefficient to grow plants, because over 50% of the radiated energy is not even in the PAR range ..
Not talking about the sun itself at all ... so you're reply is irrelevant and off topic ...
I said a cob "repoducing sunlight" would be highly inefficient to grow plants, because over 50% of the radiated energy is not even in the PAR range ..
Not talking about the sun itself at all ... so you're reply is irrelevant and off topic ...
2ANONYMOUS
Well-Known Member
Well common sense tells me any light source a person chooses to get optimal growth would be trying to get it closest to the suns meaning full spectrum..
i mean what are we really to know what radiation that we see as irrelevant might be a important factor in plants triggers or cues to produce proteins acids etc or what ever functions plants do ,, Were really at infant stage at really understanding the full potential
So sure its all about efficiency but the End game is all about plant vigor and yield which we all think comes into play tuning light spectrum
i mean a 2 month vegged indoor plant compared to a 2 month grow @ full spectrum of the sun is well day and night difference in size and yield but comparing wattage or what the sun produces per Sq meter is like a 1000 watt hid yet 8 week old plants are not in the same catagory as in size so i guess its one half dozen of this or that My goals are to try to make my Diy Cob as Full spectrum as possible
Example
i mean what are we really to know what radiation that we see as irrelevant might be a important factor in plants triggers or cues to produce proteins acids etc or what ever functions plants do ,, Were really at infant stage at really understanding the full potential
So sure its all about efficiency but the End game is all about plant vigor and yield which we all think comes into play tuning light spectrum
i mean a 2 month vegged indoor plant compared to a 2 month grow @ full spectrum of the sun is well day and night difference in size and yield but comparing wattage or what the sun produces per Sq meter is like a 1000 watt hid yet 8 week old plants are not in the same catagory as in size so i guess its one half dozen of this or that My goals are to try to make my Diy Cob as Full spectrum as possible
Example
EfficientWatt
Well-Known Member
Last attempt :
To replicate the radiant power and spectrum of the sun, with 56% efficient chips, you would need something like 3500-5000W at the plug per square meter ...
You will NEVER get 3.5 to 5 KG per square meter .... you would never get even close to 1 GPW with a replication of the suns spectrum.
If you don't want to get it, fine, I gave it my best try.
EDIT : All that unnecessary radiant IR will also have to be extracted, you better have a very powerful ventilation system too ... more wasted watts.
To replicate the radiant power and spectrum of the sun, with 56% efficient chips, you would need something like 3500-5000W at the plug per square meter ...
You will NEVER get 3.5 to 5 KG per square meter .... you would never get even close to 1 GPW with a replication of the suns spectrum.
If you don't want to get it, fine, I gave it my best try.
EDIT : All that unnecessary radiant IR will also have to be extracted, you better have a very powerful ventilation system too ... more wasted watts.
cdgmoney250
Well-Known Member
Who said anything about creating all the IR associated with black body radiation?Enough of this sunlight BS. Reproducing sunlight is HIGHLY INEFFICIENT.
Well over 50% of the sun output isn't even in the PAR range ... so a 56% efficient 'sunlight cob' would have something like 25 PAR W for 100W used at best, probably much less actually ...
As @hillbill said, we are hoping for a hypothetical "daylight" spectrum from a future horticultural based COB, within the PAR range.
Efficiency of LEDs will contine to improve as technology progresses.
EDIT: as "inefficient" as the sun is, plants still grow to their highest peak health/potential as long as they receive enough sunlight
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EfficientWatt
Well-Known Member
@cdgmoney250 : Ok, that sounds fair ... But even then the very cool blue:red ratio outdoors is not optimal for for 2 reasons (1st point isn't so much for veg but ..)):
- More leafy buds because of so much blue, redder orangy spectrums induce more bud:leaf production.
- Blue photons are much more 'expensive' energywise than red photons to produce. Photosynthesis cares about photons it can catch, not how much energy they have when they are caught. Therefore it is preferable to have as little blue as necessary, and as much orange/red as usable adequately, while keeping it all balanced enough for our plants to be happy.
@hillbill : Obviously we're talking about what actually reaches our plants in our gardens ..
- More leafy buds because of so much blue, redder orangy spectrums induce more bud:leaf production.
- Blue photons are much more 'expensive' energywise than red photons to produce. Photosynthesis cares about photons it can catch, not how much energy they have when they are caught. Therefore it is preferable to have as little blue as necessary, and as much orange/red as usable adequately, while keeping it all balanced enough for our plants to be happy.
@hillbill : Obviously we're talking about what actually reaches our plants in our gardens ..
Got any proof for that? There is a solid debate on this topic in the side by side section over on icmag. The debate is mostly about mh vs hps in flower but the mh guys are making big buds and say it has more to do with genetics.
Led provides a difference in strength over the hid equipment being that blues are more efficient and cheaper to produce. The hid setups have always penalized the blue by being more efficient in red shifted spectrums (hps) in the past.