20041216: missing line in IMGREMAP MERGEd images

>From: Unidata User Support <address@hidden>
>Organization: Unidata Program Center/UCAR
>Keywords: 200412151752.iBFHqalI029160 McIDAS IMGREMAP MERC MERGE

Hi,

One of my users is trying to create a MERC projection composite from
GOES-West, GOES-East, and METEOSAT imagery using IMGREMAP.  The
composites he creates alway have one vertical slice of missing ELEment
data; this is easily seen in an example he sent along:

http://www.unidata.ucar.edu/content/staff/tom/gifs/TEST.GIF

I have verified he problem he is reporting, and have created a simple
BATCH file that demonstates the missing element slice using Unidata
McIDAS-X v2004:

----- snip OWEN.BAT ----

REM Point at an ADDE server for a specific input dataset
DATALOC ADD RTIMAGES ADDE.UCAR.EDU

REM Create output dataset
DSSERVE ADD MYDATA/IMAGES AREA 1 9999 "All images in AREA format

REM Remap a GOES-West image into the desired MERC projection
IMGREMAP RTIMAGES/GW-IR MYDATA/IMAGES.2135 SMOOTH=YES PRO=MERC 43 LATLON=43 50 
SIZE=960 3568 RES=5
SF 1;ERASE F;IMGDISP MYDATA/IMAGES.2135 MAG=1 EU=IMAGE;MAP

REM Create an image using the western most portion
IMGCOPY MYDATA/IMAGES.2135 MYDATA/IMAGES.2136 SIZE=960 668
SF 2;ERASE F;IMGDISP MYDATA/IMAGES.2136 MAG=1 EU=IMAGE;MAP

REM Remap the GOES-East image into the same projection as for GOES-West
IMGREMAP RTIMAGES/GE-IR MYDATA/IMAGES.2137 SMOOTH=YES PRO=MERC 43 LATLON=43 50 
SIZE=960 3568 RES=5
SF 3;ERASE F;IMGDISP MYDATA/IMAGES.2137 MAG=1 EU=IMAGE;MAP

REM Composite the westernmost GOES-12 piece with the GOES-East remap
IMGREMAP MYDATA/IMAGES.2136 MYDATA/IMAGES.2137 SMOOTH=NO MERGE=YES PRO=DEST
SF 4;ERASE F;IMGDISP MYDATA/IMAGES.2137 MAG=1 EU=IMAGE;MAP

----- snip OWEN.BAT ----

What I see is a vertical line of missing ELEment values at element 669.
This should be the first element used from the GOES-East remap.

Can you verify the missing slice of elements?  If yes, do you have a
workaround?  If not, do you have any idea of what the cause might be
(i.e., where to look in imgremap.pgm)?

Thanks in advance for any help you can provide!

Cheers,

Tom