In this lab we will start using the ERDAS Imagine version 2013 image processing software package to learn some basic operations. We will also become familiar with the sentinel data to be used in future labs as well as gain experience using the USGS browsers to download Landsat satellite imagery(you can get this part in the attached tutorial document).
Google Chrome has been known to be incompatible with ERDAS help as well as the USGS Glovis site. Be prepared to try use of other browsers such Firefox or Internet Explorer if you experience unexplained problems.
Avoid having spaces in any input paths or output path names including the file name itself- some tools will not work properly if spaces are found. This has been known to affect ArcGIS products as well.
The European Space Agency (ESA), through the Copernicus program of the European Commission (http://www.copernicus.eu/main/overview), has launched three satellite sensors (Sentinels-1, 2, and 3A) providing free satellite images for the scientific community, government agencies, the private sector.Image downloaded from Sentinel-2 was used for layer stacking in this tutorial.
Landsat Enhanced Thematic Mapper (ETM+) data was used for introducing Erdas imagen software in the first part of the tutorial. The image used in this lab is a subset image cut from an entire Landsat “scene” acquired August 18, 2002 over southern Dakota County and northern Goodhue County. The subset images are roughly 666 pixels by 666 pixels, while an entire Landsat scene is about 6,500 by 6,500 pixels. The subset images are about 3 MB while a full scene is about 250 MB. These ETM+ data are 30 meter spatial resolution with six multispectral bands. The pan-sharpened ETM+ data are 15 meter spatial resolution with three multispectral bands. Later in the lab you will download another image from the USGS Glovis web site.
Different satellites have different band composites.
Band combinations for Sentinel-2. They can be found in SNAP menu, the RGB composite is as follows:
Natural Colors: 4 3 2
False color Infrared: 8 4 3
False color Urban: 12 11 4
Agriculture: 11 8 2
Atmospheric penetration: 12 11 8a
Healthy vegetation: 8 11 2
Land/Water: 8 11 4
Natural Colors with Atmospheric Removal: 12 8 3
Shortwave Infrared: 12 8 4
Vegetation Analysis: 11 8 4
Landsat 8 band combinations:
Natural Color 4 3 2
False Color (urban) 7 6 4
Color Infrared (vegetation) 5 4 3
Agriculture 6 5 2
Atmospheric Penetration 7 6 5
Healthy Vegetation 5 6 2
Land/Water 5 6 4
Natural With Atmospheric Removal 7 5 3
Shortwave Infrared 7 5 4
Vegetation Analysis 6 5 4
Landsat 4-7 band combinations
Standard false color composite 4, 3, 2 [from top to bottom]
True color composite 3, 2, 1
False color composite 4, 5, 3
Download links: just one click to download