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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 08:25:35 -0600
Hi Angel,

re:
> I am obtaining radiances from a Meteosat10 visible image (band 1, 0.6 um)
> defining first the unit as "RAD" (data cunit/'RAD'/) and then using the
> mcaget subroutine in a mcidas program
> 
> mcaget(name,msorts,sorts,cunit(i),'I4',MAXELE*4,1,idir2, handle(i) )
> 
> I have written the results in the attached file "alex-aot.log" and radiances
> are the column 9 however I am not sure about the exact units. I did`t find
> a clear document about units when programming mcidas commands I guess they
> are milliwatts/meter**2/steradian/(cm-1) because is what you get using the
> AXFORM command with keyword UNIT=RAD.

I believe that is correct. You should be able to verify this through
use of the IMGPROBE command.

re:
> I need to transform them to W/m2/um in order to estimate AOT (aerosol
> optical thickness).

OK.  Are you asking a question here, or was the main thrust of your
email the question about units above?

Cheers,

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