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[Support #ARA-684823]: ADDE access to remote servers



Hi Julia,

re:
> Yes, I am using RAW images of GOES-12. Indeed, all area files of GOES-12
> are RAW, right?

In general no; for 10-bit data yes.  You can do an IMGCOPY of GOES-12 data
into a local file and convert from 10-bit to 1-byte using the STYPE=VISR
keyword.  The resulting image is still from GOES-12, but it is no longer RAW.

> I have used IMGCOPY to copy area files to workdata
> directory to test some McIDAS commands.
> 
> "McIDAS commands use that calibration information to output calibrated
> data values." What do you mean? For example, how does it affect the output
> of AXFORM.

What I mean is that if a 1-byte AREA is created from a 10-bit image
(like is done when specifying STYPE=VISR on an IMGCOPY), and you then
run AXFORM, the output will represent the 1-byte data.  If you run
AXFORM on an AREA that has 10-bit data, then the AXFORM output represents
the 10-bit data.

> I attached the .HDR file. The description of .A01 file
> indicates that the unit is none. Does it mean that the ASCII text is the
> digital counts before calibration?

I believe so, yes.

re: check out IMGPROBE

> Is it possible to save the output of IMGPROBE to a file instead of on the
> text frame?

Yes.  Specify the global McIDAS keyword DEV=T fname.  This will save the
output into a 'text' (ASCII) file of name 'fname'.  To learn more about
global McIDAS keywords, please checkout the Unidata McIDAS-X Users Guide
appendix on global keywords.

IMGPROBE might be the routine you really want to use since it can list
data that has been calibrated.  AXFORM simply lists out image values (like
counts) from the AREA file.

One other comment is probably in order for the visible data from the GOES
satellites: the visible channel is not routinely calibrated.  This means
that the values that the satellite will measure will change over a period
of time as the sensor degrades.  The IR channels, on the other hand, are
routinely calibrated.  Calibration of the visible channel is one of the
big improvements that is supposed to be made on the next generation of
GOES satellites.

Since it seems that you are working with the visible data only, I suggest
that you do some web searching (Google searches) to see what others have
to say about using the visible data from GOES.  I am sure that you will find
some relevant information from the satellite researchers at SSEC/CIMSS and
CSU/CIRA.


> By the way, IMGDISP EAST/ALL.0 BAND=1 doesn't display the image. I have
> tried other positions from the result of IMGLIST ALL EAST/ALL. But not
> successful to display the image.

Hmm...  are you sure the image to be displayed was during daylight hours?
Did you try leaving off the '.0'?  Was the result the same?

I just displayed an EAST/CONUS image for 22:40 UTC with no problems.  That
image, however, was not the latest from the EAST dataset.

> But from the ASCII file .A01 produced by
> AXFORM, it shows there are values.

That is very interesting.  I don't know what it means other than there possibly
being a bug, or the image time was after dark and you are trying to display
a visible image.

Cheers,

Tom
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Ticket Details
===================
Ticket ID: ARA-684823
Department: Support McIDAS
Priority: Normal
Status: Closed