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[GEMPAK #KDY-987248]: GOES16 netcdf files

Hi,

re:
> Hi, my name is Laura Pappalardo and I'm trying to ingest GOES16 netcdf
> files in gempak.
> 
> I attached a .nc files as an example and the screenshot of what gempak
> shows. I can't find if there is a problem with the file generation or if
> there is a problem with gempak.
> 
> Thank you very much for the help!

The following information was provided by a community GEMPAK expert:

  There is a GEMPAK table that sets the min/max pixel values for an image:

  $GEMPAK/tables/sat/imgtyp.tbl

  The max values for GOES16 and GOES17 non-visible imagery need to be adjusted.
  I tested with a Channel 4 image and had to set the max value to 128. I did
  this because the NetCDF file says that the data range is 0-4095. However to
  map to the color tables, the data is scaled to 0-255 by shifting to the right
  4 bits. This should work, but I found that the data range for the image I
  tested is actually 0-2082. When this range is shifted 4 bits, the range 
becomes
  0-(about)130. Modifying imgtyp.tbl with the new max value makes the colors 
look
  correct.

Please try adjusting the imgtyp.tbl file in your distribution in the manner
suggested and let us know if your display(s) are what you expect.

Cheers,

Tom
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Ticket Details
===================
Ticket ID: KDY-987248
Department: Support GEMPAK
Priority: Normal
Status: Closed
===================
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