C2X processing chain for S2-MSI L1C

Optical Toolbox
9

First I performed the empirical approach with C2RCC atmospheric correction under following tutorial. https://rus-copernicus.eu/portal/wp-content/uploads/library/education/training/HYDR02_FreshWaterQuality_Tutorial.pdf

Then I used the following atmospheric corrections with this empirical approach by same steps what I used in C2RCC processor.

  1. Sen2Cor
  2. C2X
  3. C2X Complex
    Difference between min. and max. value was too high after Sen2Cor - #3

Of course in my first attempts I applied the BandMath by following expressions

image
image1891×1008 231 KB

But the result was unexpected that the minimum Chl-a concentrations were always negative (-20 microgram/leter) in all 3 atmospheric correction.
Then I applied the following expression, in order to eliminate negative values. Unfortunately the result was same again (the minimum Chl concentration were negative, and maximum value were too high(300-500 micrometer/leter) )

image
image1672×951 162 KB

I mean in Sen2Cor, C2X and C2X complex similar negative min values were calculated.
I would like to kindly ask how to process C2X and C2X complex nets without minus values.

And can you answer this question?