What is you input data and processing level?
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TOA and NDWI
Dear Community,
I want to analyse Sea Ice in Hudson Bay and want to use the NDWI for it. Of course I need to do a TOA Correction first, where the error occurs "The computed reflectance values are outside of the reflected range (0-100). Please review your radiometric calibration and coefficients values and units." What does this mean?
I still get an output, so I tried working on, but whenever I use the Raster Calculator for the statement "(%1-%2)/(%1+%2)" for NDWI, I receive a full black image and the error "bad file in channel assignment".
What do I have to do to get my results
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I downloaded Landsat-8 Files from USGS Earth Explorer, which contain Band 1-11 + BQA-TIFF. Then I translated the Bands I need (3,5,6,7; in case I want to do a NDSI) to .pix-Format and merged them. Then I process the TOA and next would have been NDWI.
I noticed my merged Bands do not have metadata. Maybe this is an explaination?
Other than that, I tried to do a TOA manually by calculating gain and offset from the metadata, but this did not work either.
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When using ATCOR it is recommended that you use the mtl file as the input. The Landsat-8 metadata will be read in directly by the ATCOR GUI. The ATCOR tutorial outlines how to correct Landsat-8 imagery - https://support.pcigeomatics.com/hc/en-us/articles/360015824152-ATCOR-Ground-Reflectance-Workflow-Geomatica-2018.
I would then recommend calculating NDWI using the TOA output image. Once you have completed the processing, you can export a subset of the channels to a new file using Focus > Files > Utility > Translate.
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Hello,
I have practically the same problem and I would like to understand, why the error "bad file in channel assignment" occures.
After calculating ATCOR I would like to calculate NDSI, but in Raster Calculater occures this error.
Is something wrong with my file, it's path or format?
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