Apogee SQ-420 vs SQ-520 for LED's

[Peter K]

Hi all,

So I'm really wanting to get a PAR meter and was looking at the apogee usb ones, but I run only LED's so I was wondering if the extra $100+ for the SQ-520 is worth it over the SQ-420. I have seen reviews where they say the margin of error isn't that much different or there is a correction equation can that be used. Does anyone have experience with the SQ-420 on LED's?

Thanks all!

 

[Peter K]

Bump

 

[uttermann]

Looks like a recent thread on the topic here that got more traction:
Apogee SQ-420 USB Par Meter | REEF2REEF Saltwater and ...

I'm leaning towards the SQ-420 myself. Looks like the biggest area of concern is in the ~400-450nm range where, the SQ-420 response drops off significantly, however in BRS's testing they showed that even with a very blue light the response was only ~12% low.

https://www.bulkreefsupply.com/video/view/brstv-investigates-what-par-meter-is-the-best/