hi, I am using ENVI 4.8 and i'm trying to do something here... I have a Surface reflectance(SR) image which has clouds in it I have one hdf file with 3 bands in it which are clouds data... I have a mosaic of the SR and 3 cloud bands.... cloud values of 1 and non cloud values of 0. I need to create an ROI where surface reflectance clouds are NOT present (i.e., equal to 1) and using THAT as a mask to mask that out of the SR Image. Is there an easy way of going about this? I been reading the Help file and i'm confused about what it is i want to do... "Build a mask" (but how, Mask Finite or Mask NaN ) or Something ROI related? Thanks for any assistance..