modis true color (brightness temperature error&display-seadasVA)

By mimoyski Date 2011-04-16 15:28 Edited 2011-04-17 04:15

hi...

i'm trying to generate modis-terra true color (w/ seadasva_6.2 updated), similar to the browse images in the data order website . was able to create L1b file (using l1bgen_modis). i don't really know how to proceed after this. i've tried the ff:

1) 'l1brsgen,4'-gives this:
   ----------------------------------------------------------------
   "No brightness temperature conversion provided for this sensor.
Error loading brightness temperature table"
   ----------------------------------------------------------------
There was a post and workaround about brightness temperature load error in
seadasva6.1-l2gen. accdg to the thread later versions would address the issue.
was the fix incorporated in seadasva6.2? or maybe a workaround that can
be used--this time for l1brsgen?

2) 'display'- only accepts L1b file. selected 24-bit, three EV_1km_Ref (412,547,667) parameters (though i didn't really know which to choose :-/ ) displayed a b/w image. loading color LUTs would result to false colors.

3) 'Utilities>data visualization>load true color image' - only accepts SeaWiFS L1A,L2, others. selected 'others' and tried to input L1b, but error message says this file was not yet supported.

does this mean seadasVA cannot display modis true color yet? is there a workaround for this?
hope somebody could help. thanks!

By @sean Date 2011-04-18 13:32

The brightness temperature tables are found in the following locations:

MODISA:    $OCSSWROOT/run/data/modisa/cal/bt_modisa.hdf
MODIST: $OCSSWROOT/run/data/modist/cal/bt_modist.hdf
HMODISA: $OCSSWROOT/run/data/hmodisa/cal/bt_hmodisa.hdf
HMODIST:   $OCSSWROOT/run/data/hmodist/cal/bt_hmodist.hdf

($OCSSWROOT is equivalent to $SEADAS)

If you do not have these files, you'll need to updated your data directory:
   ftp://samoa.gsfc.nasa.gov/seadas/seadas/seadas_modisa.tar.gz for (H)MODISA
   ftp://samoa.gsfc.nasa.gov/seadas/seadas/seadas_modist.tar.gz for (H)MODIST

Regards,
Sean

By mimoyski Date 2011-04-29 15:18 Edited 2011-04-29 15:50

hi, can generate and display true color images now (although worked only for MODIS-terra. it's still looking for Reflective LUT in Aqua). but at least i can get truecolor images now. thanks sean!!! :-)