Landsat-8 FLAASH processing results in empty SWIR bands in ENVI 5.1

ENVI's MODTRAN-based atmospheric correction tool, FLAASH, is used to convert radiance data to at-surface reflectance.  For multispectral dataset processing, a spectral response file (filter function) is required as part of the correction model.  Spectral response files (filter functions) define the spectral sensitivity of each band of the multispectral instrument.  ENVI provides these filter functions for the multispectral data formats supported in FLAASH.

With the release of ENVI 5.1, Landsat-8 (OLI) support was added in FLAASH which includes the Landsat-8 filter function.  When ENVI opens Landsat-8 data files using the _MTL.txt, several files are opened in the Data Manager.  The visible and SWIR bands are opened as a single 'meta file', while the panchromatic, thermal, cirrus, and quality bands are opened separately. 

However, the default filter function used in FLAASH includes the Cirrus band from Landsat-8, which causes a mismatch of the Landsat-8 VIS-SWIR bands and the appropriate filter function band.  This results in empty (all zero) SWIR bands after FLAASH processing. 

An amended filter function for Landsat-8 is included in the ENVI distribution in the following location:

     C:\Program Files\Exelis\ENVI51\resource\filterfuncs\landsat8_oli.sli

In FLAASH, go to the Multispectral Settings and change the default path to the above directory.

 

Note: This issue is resolved in ENVI 5.2.

Written by MM , reviewed PS 9/15/2014