Module 3 - Intro to ERDAS Imagine and Digital Data

    This week, in the third Photo Interpretation and Remote Sensing lab, was an introduction in using ERDAS imaging and Digital Data. 

    The first part of the lab had us learn on how to calculate wavelength, frequency, and energy of EMR. Although we do not need to calculate them for remote sensing, it is good to learn and understand it. This had us use the Maxwell’s wave theory (C = λν) and the Planck Relation (Q = hν). With the calculations brushed up on, we then opened ERDAS.

    In ERDAS, we went through the steps to learn and utilize the program. These were minor things like how to zoom in and out, to fitting the layers to the window. It was expanded on when looked at our raster options for adding images, as well as navigating them and adding more windows to look at more data. This even extends to the map we made in the lab. As you can see below it is a mixture of ERDAS and ArcGIS pro. This is because ERDAS is not the best when it comes to map making, so we cut a part of the image in ERDAS and exported and made a map with it in ArcGIS.

    In the second part of lab, it was more about examining the metadata of our photographs and their attributes. This first started with examining the layer metadata with each section explained. This then let us understand and compare the spatial resolution and radiometric resolution of our images. As with spatial resolution, the smaller the pixel size there is more spatial resolution, which goes both ways as the larger the pixel size, the less spatial resolution there is. Which is the same with radiometric resolution, where more pixels do mean more radiometric resolution. The last part of the lab had us get more into the weeds with ERDAS as we learned to select data, calculate area, and create statements in ERDAS. This is a bit harder to explain, but we used tables to calculate the percent area of the image we were looking at. Which is to say, we utilized ERDAS more like excel to calculate the area of the soils. Which ended with the last part, where me made a statement that matches with a specific soil

    While not like the previous lab, this was a good introduction to use ERDAS. 



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