Dear Marisena, The tool you have been using is the only tool specifically designed for that type of color matching during mosaicking in ENVI. I wonder if you have calibrated your Landsat 8 images to radiance, and applied an atmospheric correction? That might help make the images look more similar. If you know of another algorithm that you would like to apply to your images, you can apply almost any algorithm using ENVI's Band Math or Spectral Math tool. Band Math can be used to apply an expression that results in a new image. Spectral Math can be used to apply an expression that results in a new spectrum. - Peg Exelis VIS