[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

[McIDAS #SKX-144523]: himawari data tranfers from open archive



Hi Nick,

Well, it sounds like you had a very busy weekend!

re:
> Hi Tom (Whittacker?),

No, I'm Tom Yoksas.  Tom Whittaker is a good friend of mine, but he was not
in Unidata, he was in the University of Wisconsin's (UW) Space Science
and Engineering Center (SSEC).  Tom retired a year ago this past December
31, but he still "lurks" on a couple of the email lists that we manage
and chimes in when he can contribute information that others may not have
at their fingertips.

re:
> I Think I’ve got it, the Cal Block is using int32’s, not uints like
> the directory.

Actually, all words in McIDAS AREA file headers are 32-bit integers.
If you are treating some of the words as 64-bit quantities, you
will be misinterpreting their meanings.

re:
> With int32’s the values in the cal block now look reasonable and
> bandnum is 3 at index starting at 0.
> wavelength is word 8 in cal_block
> gain is 9
> offset is 10.

The band number is also available in the main AREA header.

re:
> sorry to bother you, but sending the emails helped me to work out my
> errors, so thanks for being there.

:-)  I was going to dive into your problem today after taking the weekend
off.

re:
> the only thing i want to check is the units of the radiance from the AREA
> files — are they the same as the Himawari standard and if there is any
> update to about anyone you> know of who is working toward atmospheric
> correction and water products?

As far as I know, the radiance unit is the same for all visible imagery
stored in McIDAS AREA files.  If this does not match what JAXA is
saying, I would be very surprised.  Are you saying that they are not
the same?

If you want/need me to investigate further, I will download some Himiwari
imagery from the SSEC Data Center and do some poking around.

Just to reiterate, however, you are working with a Band 3 image, correct?
If yes, this is very interesting as I have another McIDAS user that is
looking at Band 3 Himiwari imagery in McIDAS AREA format, and the unit
listed in his AREA file was REFL.  Since REFL is not a known name of a
Himiwari calibration type in McIDAS, the user was unable to display
(McIDAS IMGDISP) the image.  The other thing that is strange is the
McIDAS listing (IMGLIST) for the image does not have information for
what Himiwari Band 3 means, this is odd since it should be:

0.64 um Daytime clouds and vegetation

according to what is in the McIDAS SATBAND file.  I am going to be
investigating why IMGLIST is not getting this information from SATBAND
today.

Cheers,

Tom
--
****************************************************************************
Unidata User Support                                    UCAR Unidata Program
(303) 497-8642                                                 P.O. Box 3000
address@hidden                                   Boulder, CO 80307
----------------------------------------------------------------------------
Unidata HomePage                       http://www.unidata.ucar.edu
****************************************************************************


Ticket Details
===================
Ticket ID: SKX-144523
Department: Support McIDAS
Priority: Normal
Status: Closed