Success with LED and SPS

[chatyak]

Originally Posted by sphelps

It's a common misconception that a typical PAR meter can be used to accurately measure PAR of LED fixtures.

Yes, this is why I stated that it is under-rated, especially on the blue colors.

[sphelps]

Originally Posted by chatyak

Yes, this is why I stated that it is under-rated, especially on the blue colors.

Yes and no. A typical meter will present a lower number for blue only but this number will still be relatively high in comparison to other light sources that appear brighter. The narrow peaks from LEDs in general force higher PAR numbers from a meter while not representing how much of the spectrum range used for photosynthesis is actually being filled.

[chatyak]

If a PAR meter is used - it should also be put on electrical mode and not SUN I think... it will help a tiny bit - but overall it should be used as a gauge, even with the margin of error. Better than no meter I say.

[Reefer Rob]

I have an SPS PAR meter. Very special color changing indicators

[sphelps]

Originally Posted by Reefer Rob

I have an SPS PAR meter. Very special color changing indicators

That's the only indicator I would accurately rely on

[Aquattro]

Originally Posted by Reefer Rob

I have an SPS PAR meter. Very special color changing indicators

Agreed