To make this tutorial beginner friendly, a basic introduction to what raster data is will be important. As many GIS texts approach the subject, it could be good to introduce the subject with showing how images are raster data (RGB).
Important concepts:
Cells
Resolution
Bands
A basic visual would be helpful. Regina Obe and Leo Tsu's explanation in PostGIS In Action does a great job introducing rasters.
To make this tutorial beginner friendly, a basic introduction to what raster data is will be important. As many GIS texts approach the subject, it could be good to introduce the subject with showing how images are raster data (RGB).
Important concepts:
A basic visual would be helpful. Regina Obe and Leo Tsu's explanation in PostGIS In Action does a great job introducing rasters.