MPH/CHL Processor error

Hi everyone, Hi Dr. Matthews,

Im writing about this very useful tool to monitor lakes, the MPH/CHL Processor. I tried to test the tool (using SNAP 6) with a Sentinel 3 OLCI image and got the following error:

An internal error occurred during the target product initialisation.
Type: NullPointerException
Message: null

Can you help me with these?

I did not fill the "valid pixel expression"field. Could you help me understand what is this for? And I leave the "cyano max value"and “chl thresh for float flag” with the default values. Are these values callibrated to be site specific?

One last question: Is this approach valid for deep reservoirs (depth>30m)?

Best Regards
Omar