Hi I am working with remotes sensing images Landsat 6693x7974 pixels, when I save them as .tiff in envi and read them into matlab it is all fine but when I save a subset of them, using "file" option, the images look ok in the windows directory preview but matlab reads them wrong. Less spectral resolution basically, and lower values (instead of 200 maximum value, it gives 30). Why is that? the class of imported files is always uint8. Then when I reopen the same subset images in envi they are opened as color images, three channels instead of just a single gray level image, which is what I want. can somebody give me a clue? In Matlab help I read "If a file contains CIELAB color data, imread converts it to ICCLAB before bringing it into the MATLAB workspace because 8- or 16-bit TIFF CIELAB-encoded values use a mixture of signed and unsigned data types that cannot be represented as a single MATLAB array." does it have to do with the problem?