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Calibration file - natalia - 22-Mar-2019

Quote:We are trying to use ATCOR 4 with some data generated with a camera VNIR 1600. Is there any CALIBRATION file for this camera?

The calibration file was required for older Hyspex files for conversion of DNs to at-sensor radiance in mW/(cm2 sr micron), which is the unit for ATCOR.
As far as I know Trond implemented a preprocessing step in the level1 processor of Hyspex which does this step beforehand, but uses SI units, ie. W/(m2 sr nm). So, a factor of 100 is required for conversion to the MODTRAN/ATCOR standard units. The calibration file thus contains a factor of 100 for for c1 in each spectral band.

If it was an older Hyspex file, the calibration constant needs to be derived from the conversion factor in the ENVI header of the file.