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[McIDAS #VNL-740758]: Radiances in mcidas, Angel

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  • Subject: [McIDAS #VNL-740758]: Radiances in mcidas, Angel
  • Date: Mon, 15 Jul 2013 15:46:20 -0600
Hi Angel,

re:
> I try with the IMGPROBE command but no units are specified for RAD as shown
> in the attached file.

Here is an example IMGPROBE output for GOES-East thermal IR (10.7 um) imagery:

DATALOC ADD EAST goeseast.unidata.ucar.edu
IMGDISP EAST/FD BAND=4 STA=KMIA
PC C
IMGPROBE MODE=N

     Image Name           Day      Nominal Time   Scan Time    Band
  ----------------      -------    ------------   ---------    ----
  EAST/FD.5           15 Jul 13196   20:45:00      20:51:43       4

                        File     Nominal  Image     RAW         RAD         
TEMP        BRIT
       Lat/Lon      Line/Element  Line/Element                   *           K
 26:44:16 / 78:56:02   661/ 2206    5265/14685          10496      59.733      
264.00         132
 *   milliwatts/meter**2/steradian/(cm-1)

IMGPROBE: Done

This shows that the units of radiance (RAD) are 
milliwatts/meter**2/steradian/(cm-1).

Comment:  If this same image is converted to a 1-byte version of itself, 
IMGPROBE
will not list out RADiance.  I assume that this is because information has been
lost in the 10-bit -> 1-byte conversion.

re:
> The second item was not a question it was the reason why I need to know the
> exact units of radiances.

OK, I understand now.

Cheers,

Tom
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Ticket Details
===================
Ticket ID: VNL-740758
Department: Support McIDAS
Priority: Normal
Status: Closed