The reflective bands are placed in one file, the thermal band(s) in another file. There will be a 15m panchromatic file for ETM and OLI sensors and a 30m Cirrus file for the OLI sensor. While you can work with these data as they are, ENVI has only created a temporary virtual layer stack that is constantly resampled as you move around the image. You should save each file as a new dataset. From the ENVI main menu select File | Save As, pick the file you wish to save, and in the Save File As Parameters dialog select the Output Format ENVI. Then in the Output Filename box navigate to your work area and enter an appropriate file name.
Once this is saved as a new file, the uncompressed “.TIF” files and the “.tar” file can be deleted. The Level 2 Surface Reflectance product has been converted by the USGS from digital numbers to surface reflectance. Each data layer will end in … _T1_sr_band1.TIF (or band2.TIF, band3.TIF, etc.). As of this writing the USGS provides the original Level 1 metadata TXT file, which does not correspond to the supplied Level 2 data files. As a result, ENVI cannot open these data files directly from the MTL.TXT file as it can with Level 1 data described above. You must open each data layer individually, then create a layer stack, and finally save the result as a new file. Open all 6 or 7 … _T1_sr_bandn.TIF files in ENVI as grayscale datasets. In the Toolbox search box type layer to find the Layer Stack tool and open it. Click on the Import button and add the 6 or 7 images.
Carefully check that the images are in the correct order, i.e. Band 1 is followed by band 2, band 3, etc.
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