^^ our plants DEFINITELY use 630nm, just to clarify.
I know. Either you confused my words, or I made a confusing statement. I was meaning comparing the plant using more 630 then 520..
PAR and PUR. Which is usable light. The more green you have the less usable light therefore lower par. You have par and lumens confused. The more green the more lumens. The more usable light there is the higher the par, so par does matter. Unusable light is subtracted from the amount of usable light. par is measured in umole/s. That is an abbreviation term for micromoles
Plants absorb 20% of green and yellow. Green wavelengths helps plants to absorb more photons in other areas. So not having green will have less par than having the right amount of green. Any amount of green over that 20% will lower par.
I think your confusing what a plant wants vs. a PAR meter reading.. PAR meters read 400nm to 700nm. any light in those wavelengths contribute to the PAR reading.
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Any amount of green over that 20% will lower par. " see I think your confused, as a PAR meter will register green regardless of intensity, it will not lower a PAR reading, it will only increase a PAR reading.
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The more green you have the less usable light therefore lower par" not when talking about PAR reading.
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Unusable light is subtracted from the amount of usable light." there is no meter in the world that does this, as it's even impossible to talk what data to assign a color spectrum on a made program. also what is usable light and unusable light in your definition? the definition of a PAR meter is to calculate 400nm to 700nm
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The more usable light there is the higher the par, so par does matter" whats even your definition of "usable light" ?once again any light in 400nm to 700nm will contribute to a PAR reading. no PAR does not matter when comparing lights, as each and every light is a different spectrum. the only time you can compare a PAR reading is when using the same object over and over.. using a HPS one round, the same HPS second round, the same HPS third round.. as that is given the exact same data to go off of, as the spectrum does not change. if you were to compare a HPS PAR to a LED PAR, this is a waste of time, as the spectrum has just changed, so it's pointless to compare the PAR number.
Also, no, PAR does not matter once again, as I explained above: "
want a 1000 PAR reading at 24 inches? what if I told you it was a all green panel."
all you should be using a par meter for is to see canopy lighting, to get as even lit as possible ( talking about center and edge ). there's really not much more you can do with it. as stated you can use it to build data if using the same lamp over and over, but that's about it, or to see the "aging" of a lamp. you can't even use it on say a XM-L vs a XM-L2 as the spectrum changed, so to compare the PAR reading with the XM-L to X-L2 is pointless once again. even when the new area 51 panels come out, it would be un-wise to compare there old PAR reading to there new PAR reading, as the spectrum is guaranteed to change. which would meaning trying to compare two things that can never be compared ( or shouldn't )
