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Due to licensing issues with Raytheon, we can not provide the source code for the VIIRS programs.

Don

l2gen does not support MODIS collection7 yet. We do not have LUTs that calibrate MODIS collection7 correctly. Currently you need to get the L1A file from us or LAADS which must be an HDF4 file. To get the correct calibration use modis_GEO and modis_L1B to get the GEO and L1B files to feed into l2gen...

Lets make sure the correct version of l2gen is installed.
This is what it should be:

dshea@gs616-analysis703:~$ ODPS/odps-test/bin/l2gen --version
msl12 10.2.0-V2026.3 (Jun 18 2026 17:32:07)

don

I believe the "git" protocol requires a configured ssh public key. Try http instead:

git clone https://git.smce.nasa.gov/oel/ocssw.git

don

What version of OCSSW are you running? You might want to try installing the "--arch=odps" if your linux kernel is new enough to see if that helps. When I run a MODIS granule at resolution=500, I get mostly CPU saturation. If you are not CPU or IO limited and the memory is only about 1.2G, ...

I just tested this. The l2gen executable delivered in V2026.0 does not need the instrument_defaults.par file. Could you be running an older version of l2gen with the V2026.0 version of the share data? This is the version of l2gen in V2026.0 l2gen --version msl12 10.0.0-V2026.0 (Mar 11 2026 20:00:27)...

To simplify the inner workings of l2gen for VIIRS we no longer support giving l2gen a VIIRS L1A file as the ifile. The ifile needs to be an L1B. Use "calibrate_viirs" to make an L1B from the L1A. calibrate_viirs ifile=viirs.L1A.nc l1bfile_mod=viirs.L1B.nc l2gen ifile=viirs.L1B.nc ofile=vii...

At 500m you might be running into a cache size problem with l3mapgen writing NetCDF. Try running l3mapgen with "deflate=0". The file will be a lot bigger without compression, but this should speed up processing if the cache is the problem. You can always run h5repack on the file to compres...

MODIST lasted longer than one of the internal tables could handle.
Need to use T20025.16 or later. See:

viewtopic.php?t=7294

don

The problem is that we did not expect Terra to last this long... We only had space in the code for 300 date records and the current xcal file for modist (xcal_modist_txc_oc_v4.12b) has ndates = 307. The fix for this first appearers in T2025.16 so any tag after that should work. Sorry it is not in an...