er-mappererdas-imagineremote sensing
I am a new user in ERDAS imagine and i found it hard to turn the single band raster data from grey color to pseudocolor using ERDAS imagine.
This process could be easier to be performed using ER Mapper but i can not found that there are existing color scheme available in ERDAS for better visualization purpose.
Try using the layer stack tool in the Spectral pull-down in the raster tab. 
Select the bands you want to use in the tool. For example, I'm selecting band 1 to separate the band from a 12 band raster.
Save the band you selected. The output should now be a band separated-out from the stacked image.
Have you though of just using the free GDAL tool?
http://www.gdal.org/gdaldem.html
It can run in windows using OSGEO4W and can ouput .img files.
For Imagine 8 it goes something like...
From Spatial Modeler: This model is found in the file <.IMAGINE_HOME.>/etc/models/Slope_percent.gmd.
From Image Interpreter: Select Topographic Analysis... | Slope.... Under Output units select degrees / percent or similar. To view or edit the model, click the View... button in the Surface Slope dialog.
Best Answer
While loading the image itself, in the File window you should find another Tab that allows you to open the Image in Pseudo color form.
Once done, you can view the histogram distribution and alter the color of the pixel values of your choice.
Hope this helps !!!