Reef Central Online Community - View Single Post - For the PAR inclined . Apogee upgraded sensor

oreo57 · 03/04/2016, 09:05 PM

MH w their complex spectrum could create offsetting errors. Calibrate w a green LED. Both should measure the same. If the 500 is Sig off that might give you a clue.
To be honest, I wouldn't really expect them to output equal uA. Different filter pack in the 500 would most likely create a "darker" sensor. Not to mention a different photodiode.
In other words you need a different conversion factor.
Theoretically the 500 will be low here as well. Correct the "blue centric" by the ratio.
As a side note, Apogee States they need to correct the software in the meter body. May just be a change in a scaler.

03/04/2016, 09:05 PM	#31
oreo57 Registered Member Join Date: Apr 2013 Posts: 1,793	MH w their complex spectrum could create offsetting errors. Calibrate w a green LED. Both should measure the same. If the 500 is Sig off that might give you a clue. To be honest, I wouldn't really expect them to output equal uA. Different filter pack in the 500 would most likely create a "darker" sensor. Not to mention a different photodiode. In other words you need a different conversion factor. Theoretically the 500 will be low here as well. Correct the "blue centric" by the ratio. As a side note, Apogee States they need to correct the software in the meter body. May just be a change in a scaler. Last edited by oreo57; 03/04/2016 at 09:19 PM.