[GRASS-user] i.atcorr - range/rescale issues

[Carlos Henrique Grohmann de Carvalho]

 Hello all

I'm preparing a tutorial on remote sensing with GRASS (already have 7
videos - in portuguese - here: https://www.youtube.com/c/SPAMLabUSP)

What I'm planning now is to run i.landsat.toar and i.atcorr, and then
compare the results with the surface reflectance products from Landsat
collection 2.

I got it all running but the results are a bit different and it seems that
the "range" and "rescale" options are the ones to tweak.

checking the metadata:

L2 before scale factor: {'min': '3783', 'max': '65535'}
L2 after scale factor: {'min': '-0.0959675', 'max': '1.6022125'}

L1 radiance at sensor: {'min': '-6.2', 'max': '191.6'}

L1 reflectance dos1: {'min': '0', 'max': '0.398754597845553'}

L1 reflectance 6S: {'min': '8.560894e-11', 'max': '255'}

I can use the min/max from radiance-at-sensor as the "range" in i.atcorr,
but what would be best for the "rescale" option? If I don't set it, I end
up with 0-255
values. How to get the floating-point result?

thank you for any input


Carlos


-- 
Prof. Carlos Henrique Grohmann
Institute of Energy and Environment - Univ. of São Paulo, Brazil
- Digital Terrain Analysis | GIS | Remote Sensing -

http://carlosgrohmann.com
http://orcid.org/0000-0001-5073-5572
________________
Can’t stop the signal.
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