Working with Landsat Imagery

Table of Contents

  1. Working with Landsat Imagery
  2. Setting Up Your Workspace
  3. Downloading Data from the USGS Earth Explorer
  4. Creating New Imagery Files Using the Composite Bands Tool
  5. Creating True and False-Color Composites
  6. Skill Drill: Creating a Custom False-Color Composite

Setting Up Your Workspace

In this course, we will be using a particular folder structure. For each lab activity, you will start by creating your workspace folder on the local hard drive. If you are a registered student at Humboldt State University working in a computer lab, you will use the desktop as your local hard drive location. You may also use an external USB drive if you plan to work in multiple places.

Avoid using networked drives such as Google Drive. Networked drives can increase processing time and cause technical glitches.

A workspace is a folder or series of folders that contain all of your project files. The top-level folder in your workspace, also called the project folder should indicate the lab assignment or the project. You will organize all of your work within the project folder.

On your local hard drive, create a new folder and give it a descriptive name, such as “Landsat_Imagery.” Be sure there are no spaces in the name. You may use underscores instead of spaces. Inside this folder, create the following three subfolders: originalworking, and final.

A basic folder structure used in this course

Special Considerations for Remote Sensing Projects

While the standard folder structure works well for most GIS projects, there are some issues to consider when working on remote sensing projects. The file sizes for aerial imagery and satellite data can be quite large. As you modify or derive new imagery data, your project folder can reach many gigabytes in size.

When it comes to backing up your data in the cloud, the size of your workspace folder can become a problem. Potential trouble can come from your cloud storage limits or from the time it takes to upload your backup files. One way to solve the issue is only back up important folders. For example, it may not be required to keep copies of the original imagery if they are readily available from online sources. In this instance, you may want to only back up files in your working folder or your final folder to save time and storage space.  Which folder gets backed up will depend on your needs. At the end of this activity, you will practice this procedure.

Be sure to pay attention to where you save files and maintain file management discipline.