Fixed bug in perspective script
Fixed bug in perspective script

thareUSGS/ISIS3_scripts,USGS-Astrogeology/ISIS3_scripts,thareUSGS/ISIS3_scripts,thareUSGS/ISIS3_scripts,USGS-Astrogeology/ISIS3_scripts,USGS-Astrogeology/ISIS3_scripts,USGS-Astrogeology/ISIS3_scripts,thareUSGS/ISIS3_scripts