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The light intensities shown on their website make no sense. They are giving PAR numbers without specifying at what distance from the light fixture they made their measurements. Something is missing there, or it is just a sales pitch.
 

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It would seem they agree with you, Hoppy.

"To ensure you are getting actual PPFD values over a defined growing area, the following needs to be published by the manufacturer: measurement distance from light source (vertical and horizontal), number of measurements included in the average, and the min/max ratio). Fluence always publishes the average PPFD over a defined growing area at a recommended mounting height for all of our lighting systems." https://fluence.science/science/par-ppf-ppfd-dli/

Though you're right -- I don't readily see where they define the area and distances used to make the measurements...
 

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Thank you. That is good data to keep if anyone is thinking of using one of their light fixtures. It appears to be in the range more appropriate to salt water tanks than to planted tanks.
 

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Hi Everyone,

Sorry, I'm very late in on this topic being a newcomer but...

When measuring PAR/PPF (Photosynthetic Photon Flux), a special instrument known as an Integrating Sphere is used for this purpose. It captures all the light being emitted from a light source in three dimensions. Please see the following:

https://en.wikipedia.org/wiki/Integrating_sphere

So, it is not necessary to specify distance for PPF measurements as the idea behind this instrument is to capture all the photons being emitted by the light source. However, it is necessary to specify area upon which the light is falling in most applications and this is PPFD, which is Photosynthetic Photon Flux Density. PPF is measured in micromoles/sec and PPFD is measured in micromoles/m^2/sec.

OK, having got that out of the way, I have a BML light fixture which was Fluence's previous incarnation. It was my own design but assembled by BML/Fluence. This fixture is six years old and still going strong.

I will take more time to look at the Fluence Ray details. BTW, does anyone know what it costs?

Yorkie
 
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