For our project, we used the Erdas Imagine Field Guide (3rd edition, 1995), and Introductory Digital Image Processing (John R. Jensen, 2nd edition, 1996) to help us understand the processes behind the routines. We also used the Help and View functions for a lot of the .gifs and for help understanding the underlying processes.
This project we intended to explain the image enhancement routines for spatial enhancement, radiometric enhancement and spectral enhancement in Erdas Imagine. But due to time constraints and difficulty finding a weekend when the server wasn't down, we cut the scope of our project.