How to open Landsat 8 surface reflectance in SNAP

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Hi Guys !

I’ve seen some posts about SR L8 data not opening in SNAP. Recently me and my professor came up with the idea how to open sr files and get the correct reflectance value. It turned out that it’s not problem with SNAP but an error in metadata.
Here’s a quick guide how to open surface refletance L8 data in SNAP :slight_smile: :

  1. Unzip the image folder - you should have seven bands images and MTL file
  2. Edit the MTL file from line 45 - where the names of the files are listed . You can see that the names of the images from the folder are different that this listed in the metadata, that’s why they want open .
  3. Change names of the files in the folder exp. LC81900242016130LGN00_sr_band1 change to LC81900242016130LGN00_BAND1 (so the names match the names listed in MTL file)
  4. Because it is surface reflectance we only have 7 bands, in metadata there’s more delate lines with bands 8, 9, 10 etc.
  5. Your metadata should look like this:
    FILE_NAME_BAND_1 = “LC81900242016130LGN00_B1.TIF”
    FILE_NAME_BAND_2 = “LC81900242016130LGN00_B2.TIF”
    FILE_NAME_BAND_3 = “LC81900242016130LGN00_B3.TIF”
    FILE_NAME_BAND_4 = “LC81900242016130LGN00_B4.TIF”
    FILE_NAME_BAND_5 = “LC81900242016130LGN00_B5.TIF”
    FILE_NAME_BAND_6 = “LC81900242016130LGN00_B6.TIF”
    FILE_NAME_BAND_7 = “LC81900242016130LGN00_B7.TIF”
    METADATA_FILE_NAME = “LC81900242016130LGN00_MTL.txt”

save the file, then go to SNAP open the changed MTL file :wink:

TIP. - the first time you will open changed mtl everything will work really slow, try to open product than close it and open again - should work faster.

One more thing to change radiance value to refletance in both normal OLI/TIRS L8 data and SR L8 data open the MTL FILE.
change the value in all the lines (line 102 to 112) with RADIANCE_MULT_(band number) to 0.0001

exp.
RADIANCE_MULT_BAND_1 = 0.0001
RADIANCE_MULT_BAND_2 = 0.0001
RADIANCE_MULT_BAND_3 = 0.0001
RADIANCE_MULT_BAND_4 = 0.0001

than change the value in all the lines (line 113 to 123) with RADIANCE_ADD_(band number) to 0

exp.
RADIANCE_ADD_BAND_1 = 0
RADIANCE_ADD_BAND_2 = 0
RADIANCE_ADD_BAND_3 = 0
RADIANCE_ADD_BAND_4 = 0

You will get reflectance values from 0 to 1. :wink:

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