I am using Register and Resample with a Grayscale image. When I try to resample an image with Descartes, I set the background color to BLACK. After resampling, the background color is set to Gray instead of Black.
1.) Check if Grayscale image is set to Transparency in Raster Manager. If your Grayscale image is set to Transparency, when you do the Resample turn off transparency on the Grayscale image and then run the Resample command. The background will then be Black on the output file.
2.) When you do the Resample and select your Output Image select the Options button. This will bring up a Raster Save As Settings box. Change the Color Mode to either RGB or 256 Colors and set Resampled to Yes and change Background to Black. When the output image is created it will have a Black background.
http://communities.bentley.com/products/3d_imaging_and_point_cloud_software/w/wiki/24953.descartes-register-and-resampling-output-file-wrong
http://communities.bentley.com/products/3d_imaging_and_point_cloud_software/w/wiki/26665.register-resample-warp-command-data-does-not-line-up