Module 7 - Image Preprocessing 2: Spectral Enhancement, Band Indices, and NDVI

In this week's module we focused on learning about the spectral dimensions of remotely-sensed imagery to be able to better analyze our data. For our lab assignment we were tasked to identify three key features by referencing pixel values and spikes in histograms, and symbolizing each (in separate maps) using different combination bands.

To accomplish this, we put to practice four ways of examining imagery and identifying features using ERDAS Imagine as such:

1. by examining the Histogram for shapes and patterns;

2. by visually examining an image in grayscale for light/dark shapes and patterns;

3. by visually examining an image as multispectral (by changing band combinations); and

4. by using the Inquire Cursor button.

Additionally, we learned about the Common Sensor Types, Common Band Combinations, and which ones are typically used for identifying and visually amplifying certain features for Landsat Thematic Mapper bands (as shown in the screenshot below).
Finally, we learned how to use the Help Menu in ERDAS Imagine, as well as explore the NDVI tool (Normalized Differential Vegetation Index) to understand how the formula is used to distinguish clear cut vegetation areas. This lab has increased my curiosity in Remote Sensing a whole lot.