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I just downloaded my first group of landsat 8 surface reflectance data files. In this package contains sr bands 1-7 (I hope to use some of these to create an NDVI) as well as numerous files called: sr_cloud, cf_mask, and cf_mask_conf (all tif files). I am using arcgis.

I am assuming that these files are utilised to help remove cloud coverage from the images. However, I have never dealt with any of these types of files (srcloud, cfmask, etc.) and I have no idea regarding how they work or how to use them to effectively remove clouds. Does anyone have any experience working with these kinds of files and know how I may effectively use to remove clouds?

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The cf_mask file identifies cloud (Pixel value 4), cloud shadow (2), snow (3), and water (1) pixels. Assuming you only want "clear land" pixels (0) you can use the Con tool with the following options

Input Conditional raster = "cfmask.tif"
Expression = "Value = 0"
Input true raster = "<surface reflectance layer>"

Use the composite bands tool to make a multi-band raster which can be used instead of an individual layer for RGB plotting.

The sr_cloud layer provides information about the atmospheric correction needed on the scene.

You mention you want to use the surface reflectance layers to generate NDVI, this can be done pre-delivery by the USGS if you use the ESPA interface, https://espa.cr.usgs.gov.

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