Page 14, section 1.2 has to be replaced with this text:
Have a look at the scanned map and try to find the projection used. You can use any image viewing software fort his.
- Which projection was used?
- Look for the EPSG code at http://www.spatialreference.org and write it down
In Chapter 3, roads.tif has the following legend:
- Start QGIS 3.4 Desktop
- In the main menu choose Project | Properties
- In the CRS dialogue set the projection of the project to the EPSG code that you have found (26718)
- Click OK.
0: no roads
In Chapter 3, Page 86 step 4:
1: dirt road
The default Minimum Slope [Degree] should be 0.01 like in the screenshot of Figure 4.25.