Calculating top of atmosphere (TOA) reflectance with QGIS

The data in Landsat-8 images is represented by Digital Numbers (DN). For the calculation of environmental indices such as the Normalized Difference Vegetation Index, reflectance values are often used instead of DN. The purpose of the following exercise is to calculate the top of atmosphere reflectance (TOA reflectance) with a solar angle correction for band […]

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Importing Landsat-8 imagery into QGIS

For this exercise we use a Landsat-8 image of Portugal (path: 204, row: 32). Landsat satellite data is available on https://earthexplorer.usgs.gov/. A Landsat-8 image consists of several bands, each represented with a TIFF file in your data download. Each file contains radiance data of the Earth surface within a certain window of the spectrum. band […]

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