tags420
Well-Known Member
I never said you were wrong but you are explaining two different things...intensity and spectrum. There is no way to read them in one merged reading/meter yet. Like a photosynthesis meter maybe one day...but then there has to be a more definite theory about which wavelengths are truly the most important.
Lux will not work truthfully. 1Lux is equal to 1lumen over a m2. Lux is biassed just like lumens. No bias readings with par. With par, what is present(400-700) is read equally whether it is green or red. PAR is the only measurement we(normal people) have that is unbiased in the amount of photons being emitted simple as that.(other than a $5000 spetcroradiometer of course)
The hps vs led proves mine point...that par is better than anything. If the readings were in lux with the same umols from the LED and HPS...the hps would seem better but the par value shows that there is actually the same light amount being emitted. Then after that we have to look at the spectrum and decide how well the plants will respond to it, based off our knowledge of the action response curve.
Judging a light is a multi step process and there are a few ways to go about it...but the point is that a few different measurement/reading/facts are needed to get to you final interoperation of it's capabilities. Then you have to actually use it and see if it lives up.
This is an old post of mine. Basically what we have been talking about
Lux will not work truthfully. 1Lux is equal to 1lumen over a m2. Lux is biassed just like lumens. No bias readings with par. With par, what is present(400-700) is read equally whether it is green or red. PAR is the only measurement we(normal people) have that is unbiased in the amount of photons being emitted simple as that.(other than a $5000 spetcroradiometer of course)
The hps vs led proves mine point...that par is better than anything. If the readings were in lux with the same umols from the LED and HPS...the hps would seem better but the par value shows that there is actually the same light amount being emitted. Then after that we have to look at the spectrum and decide how well the plants will respond to it, based off our knowledge of the action response curve.
Judging a light is a multi step process and there are a few ways to go about it...but the point is that a few different measurement/reading/facts are needed to get to you final interoperation of it's capabilities. Then you have to actually use it and see if it lives up.
This is an old post of mine. Basically what we have been talking about
Here is how I look at LED's in order of importance.
1) What is the par output in umol's (most companies don't give one on their website and that just pisses me off)...minimum 700umols@12" is the lowest end of my attention radar. 1000hps's puts out 1800umol@24" so that is my real goal. Yellow(lumens) light that is not all absorbed(wasted) is still in the par spectum, so 1800umols LED PAR(wavelength specific) output would be more to the plants than 1800umols PAR(the whole mess) from hps.
2) Wattage to achieve output. (first total unit draw, then diode wattage and brand)
3) Coverage size and umol dispersion over the area (only strong in center or is it spread out)
4) Spectrum/wavelengths
5) Price
6) BS advertising/company image/knock offs on the market. (maybe they are the knock offs?)
Just the ways I personally judge all of them.