Can anybody help me with creation of NDVI in Erdas 9.3?

I want to create NDVI map of landsat MSS, TM and IRS LISS III images. When I am using ArcGIS 9.3 to create the map by using spatial analysis (raster calculator, b4-b3/b4+b3), I am getting the NDVI...

12 May 2014 4,599 7 View