20010104: IMGREMAP: MAG= vs RES= (cont.)

>From: Jason Allard <address@hidden>
>Organization: PSU
>Keywords: 200010240345.e9O3jC425238 McIDAS-X IMGREMAP MAG RES

Jason,

re: use global DEV= keyword to redirect textual output
>Great, that looks like its what I want.

re: IR temperatures in McIDAS are in Kelvin.

>Hmmm...I can get the IR values in kelvin if I only 'probe' one pixel
>with ALT D...  but when I use IMGPROBE LIST BOX, I get raw values...
>more on this below.

That is because the default unit listed when using IMGPROBE LIST BOX
is 'BRIT'.  If you want to list the TEMP units, you would use:

IMGPROBE LIST BOX TEMP

The online help for IMGPROBE notes this:

IMGPROBE -- Lists or plots digital data of a displayed image
   IMGPROBE option region unit <keywords>
Parameters:
   option | display option; choose LIST, STAT, CONT, HIST or PLOT; see
            Remarks for valid combinations of option and region parameters
           LIST - lists values on the text frame for data points in
                  specified region (def)
           STAT - lists statistical parameters on the text frame for
                  data points in specified region
           CONT - contours values of data points in specified region
           HIST - displays histogram of data points in specified region
           PLOT - plots values of data points in specified region; if
                  region is BOX or LINE, a line plot is drawn; if region
                  is POINT, the value of the data point is plotted
   region | type of region to cover; choose BOX, LINE or POINT; see
            Remarks for valid combinations of option and region parameters
           BOX   - data points in rectangle defined by cursor limits or
                   SIZE= keyword
           LINE  - data points along a line defined with the mouse
           POINT - data point at center of cursor's current position (def)
   unit | calibration units of output (def=BRIT, meaning greyscale
          brightness values between 0 and 255; all available
          units are listed when LIST POINT is requested)

From this, the default if one runs:

IMGPROBE

is actually:

IMGPROBE LIST POINT BRIT

re: IMGPROBE will return all values related to the pixel being interrogated.
    In the case of an IR image, you should get back RAW, BRIT, and TEMP.
    TEMP will be in K.

>I'm working with an original GOES 7 IR image that I obtained from
>SSEC... I didn't do anything to it.  When I perform an IMGLIST command
>with FORM=EXP, I get that it is Band: 8  No Information Available....
>but otherwise, everthing looks fine.

OK.  This means that it is a single banded image.  A quick check of
the McIDAS files SATANNOT and SATBAND lead to what band 8 is:

from SATANNOT:

GOES-7                       32
GOES-7 IR          D         33

from SATBAND:

Sat 20 21 22 23 24 25 26 27 28 29 30 31 32 33
BRes 1.0 1.0
Cal VISR
 1  0.65 um Daytime cloud detection
14  0.65 um Daytime cloud detection
Cal A
 8 11.2 um Night cloud detection, sfc temp

From SATANNOT, the GOES-7 IR is satellite ID number 33.  From SATBAND,
the possible bands for satellite ID numbers 20-33 are 1, 14 and 8.
As you can see from the listing, band 8 is:

 8 11.2 um Night cloud detection, sfc temp

>I tried the IMGPROBE MODE=N, and it did give me all the possible values
>for the pixel, as you mentioned in the last e-mail...
>
>I also get all the possible values when I use ALT D... so no problem
>there.

'ALT D' simply runs 'IMGPROBE MODE=N'.

>I get only raw values when I'm 'probing' for more than one value...
>such as when I use the command:
>
>IMGPROBE LIST BOX

Use:

IMGPROBE LIST BOX TEMP

>on the original GOES 7 IR image... it give only raw values, not the
>temperature in K.  I'd like it in K.  As I mentioned before, it is an
>orginal image, and it says its band is 8

re: is image multibanded
>I don't think it is multibanded... it is merely a GOES 7 IR image...
>that says it is band 8... I thought the problem might have been a
>result of me changing it, so I went back to the original GOES 7 IR
>image.

OK.

re: use IMGCHA to change band number when you IMGREMAP an image

>I suppose I could change the band number, but to what?  It is in the
>band that it came in... and when I probe an individual pixel, it does
>give me the temperature in K.

You only need to change the band number when you remap an image into
an image that has a different band number.  Since you are dealing with
an unremapped GOES-7 image, there is not need to use IMGCHA to change
any values.

>Thanks for the help, 

You are welcome.

Tom