Merge rasters using Spatial Analyst, in ArcGIS 9.3

Question

I am getting error messages when trying to merge three orthophotos using Spatial Analyst.

I have been following the recommendations in Forum threads, and I followed the directions in the ESRI support document 20988 "Merge rasters using ArcGIS Spatial Analyst", and I followed the directions in ArcGIS Desktop Help 9.3.

I was careful to make sure each orthophoto has a different name. Also, each ortho is made of four files, and those were the same for each ortho: band_1, band_2, band_3, and band_4. I changed the names so that all 12 parts had different names. (12 comes from this equation: 3 orthos x 4 "band" files = 12)

This is the first error message I got:
ERROR 010316: Unable to open the input grid: C:\USERS\ANNAGL~1\APPDATA\LOCAL\TEMP\Z_Z_Z2 ERROR 010067: Error in executing grid expression.

When I go to the folder to see if there are files in there, I found files named "z_z_z2", "z_z_z3", and "z_z_z4", and each of these looks like a darker version of one of my original three orthophotos.

I'm not sure what I'm doing wrong, or simply what to do next.
Please help if you can -
Thanks!
Anna

curtvprice · Answer

I am getting error messages when trying to merge three orthophotos using Spatial Analyst.

I have been following the recommendations in Forum threads, and I followed the directions in the ESRI support document 20988 "Merge rasters using ArcGIS Spatial Analyst", and I followed the directions in ArcGIS Desktop Help 9.3.

This KB document is does not cover your issue - multi-band rasters.

The inputs can have any name you want (the paths make their names unique), but you need to merge them in this order:

1. Add the bands to ArcMap as individual rasters layers (3 raster x 4 bands - 12 layers)
2. Use the Raster Calculator and the Merge tool (as described in the KB article) to merge all the band 1 rasters.
3. Repeat with the band 2 rasters, band 3 rasters, band 4 rasters
4. Now you should have a raster covering the whole area for each band. Combine them using the Composite Bands tool.

The advice already given about using short raster names (< 10 characters) and avoiding paths that include spaces is sound advice, especially for 9.3.

Hope this helps.

MarkBoucher · Answer

I've found that the shorter the filepath and filename, the less likely I will have problems. 
Don't use spaces in the path or names either.

TungNg · Answer

Maybe something is wrong with the path to the files. Create a folder like C:\gis and put all the files in that folder and try again to see if that would help

Good luck!