Extract the quantification values from L2A Sentinel-2

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1

Dear Sirs,

I need the physical values from BOA reflectance of the MSI L2A Sentinel-2. For this, I computed by band math, = DN * Factor 1/10000 from ‘QUANTIFICATION_VALUE’. But, I need see the values to do reflectance graphics. How export the band reflectance BOA from SNAP in format of float32?

Thank for you!

2

You can simoply export the S2 product to NetCDF or Envi format and you will get.
If you export to GeoTiff you get the DN values.
In order to prepare the product for the GeoTiff export you can create new bands by Band Maths.
Simply use the band name as expression, set a new name and preserve the wavelength, also disable the virtual option. Afterwards you can delete the original band.
If you want to do it on a stack of products you can do it with a graph file on the command line.

3

Dear Marco, @marpet
Thank you for attention. It helped a lot.
More a question… what the unit of output? W.m²? In xml archive this is unit for Solar irradiance to conversion to bands of reflectance.

4

But reflectances don’t have a unit. It is the ratio of reflected light by the surface.
You can say that the unit is % or dl (dimensionless).
You can see the unit when you select the band and choose from the toolbar.

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