Exporting Sentinel 2 L2A mosaic with raw values

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Hello!

I am trying to export a mosaic of 2 S2 L2A images. The workflow I use is as follow :

Resampling both image to 10 meters using Raster - Geometric - Resampling. I then use both resampled image to create a mosaic using Mosaicking (I specify my desired CRS and put the pixel size to 10 meters). Finally I export to Geotiff / BigTiff.

My problem is that the resulting tiff have values for each band that seems normalized or corrected (values between 0 and 1). I need the raw value from the pixel (on the 10 000 scale). I have outputted other L2A images (no mosaicking) without problem, that is why I suspect the mosaicking as the problem, but I tried many variances and cannot find how to do it. Is it because such rescaling is necessary to perform a good quality mosaic? Would there be a way to restore or extrapolate the raw values after the mosaic?

Any insights are welcome :slight_smile:

Thank you!

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You can invert the scaling which is done when converting from DN to reflectance.
The general equation is
refl = raw * factor + offset
The inversion is:
raw = (refl - offset) / factor

For S2, the factor is 1/10000. The offset is -1/1000 after Processing Baseline 4.0. Before it was zero.

The mosaic is creating a new generic product and does not preserve the specifics of the inputs.

EOMasters_icon_60 Marco from EOMasters - Mastering Earth Observation - Kofi_cup_40x30

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