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Hi Bernie, re: how to convert a McIDAS image into a format usable by IDL; try AXFORM > Thanks for your detailed reply. This is very helpful. No worries. re: > There does seem > to be a way to read Geotiff images with IDL using some routines > developed by David Fanning at NSIDC. I need to look into this further. OK. The things you will want to investigate are: DSSERVE -> create an output dataset of type GeoTIFF IMGREMAP -> remap the image into a rectilinear projection After creating the appropriate output dataset of type GeoTIFF, you would remap the input image into a RECT projection in the output dataset. Here is a snippit from the online HELP for DSSERVE that should get you going: HELP DSSERVE DSSERVE -- Manages and lists ADDE dataset names on the local server DSSERVE ADD dataset format bfile efile <keywords> "comment DSSERVE DEL dataset DSSERVE LIST group format Parameters: ADD | adds a new ADDE dataset name to the local server DEL | deletes an ADDE dataset name from the local server LIST | lists the ADDE dataset names on the local server (def) dataset | ADDE dataset name to add or delete; must be specified in the group/descriptor format; see Remarks for restrictions format | file format; valid formats include AIRS, AREA, GEOT, GRIB, GRID, LV1B, MD, MOD4, MOD8, MODR, MODS, MODX, MSGT, MTST, NCDF, SYSN and TEXT (no def for ADD; def=all formats for LIST) bfile | beginning file number assigned to the ADDE dataset; 'bfile' and 'efile' are required for AREA, GRID, MD, NCDF and SYSN formats efile | ending file number assigned to the ADDE dataset "comment | comment describing the ADDE dataset; max of 80 characters; the comment cannot contain an equal sign (=), apostrophe (') or comma (,); the text entered in this field is visible to the client when they list the dataset with the DSINFO command group | group name (def=all groups) Keywords: DIRfile='mask' | directory and/or file mask to locate files for the non-McIDAS format servers; can also be used for the McIDAS area, grid and MD file servers if the files are not in the MCPATH directories, REDIRECT directory, or have names other than AREA*, GRID* and MDXX*; do not specify bfile and efile when using this keyword; see the Remarks INFo='info' | additional information for the server about the data; required by some servers but not needed or used with McIDAS file formats AREA, GRID, MD and SYSN; 120 characters maximum; the beginning and ending single quotes are mandatory; see the Remarks TYPe= | data type of the dataset created with the ADD option; valid types are GRID, IMAGE, NAV, POINT and TEXT; this keyword must be specified for all non-McIDAS file formats (e.g., NCDF) except TEXT (def=IMAGE for AREA format; def=GRID for GRID format; def=NAV for SYSN format; def=POINT for MD format; def=TEXT for TEXT format) Remarks: ... ************************ GeoTIFF Dataset Remarks *********************** GeoTIFF images are similar to TIFF images, but include calibration and navigation information. They are used by the GIS community and can be viewed with ARCVIEW or other GIS software packages. You can create GeoTIFF image files from other TYPE=IMAGE datasets. To do so, make a GeoTIFF image dataset with a DSSERVE command similar to: DSSERVE ADD GEOTIFF/GOES GEOT 1 9999 TYPE=IMAGE "GeoTIFF GOES image files. Then specify GEOTIFF/GOES as the destination dataset with a positive position number in an IMGCOPY, IMGFILT, IMGOPER or IMGREMAP command. If you use IMGCOPY, IMGFILT or IMGOPER, the source image must be in a rectilinear projection. If you use IMGREMAP, the source image can be in any projection, but you must specify PRO=RECT to make the destination GeoTIFF image a rectilinear projection. IMGFILT, IMGOPER, and IMGREMAP save the image with BRIT calibration. IMGCOPY can save it with other calibrations by using the UNIT keyword. The output file name consists of the descriptor name and position number followed by ".tif". For example, the command IMGCOPY GOESEAST/VIS GEOTIFF/GOES.300 SIZE=ALL creates an output file named GOES0300.tif. The procedure is pretty easy once you get the hang of it... 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: SSN-755786 Department: Support McIDAS Priority: Normal Status: Closed