The Log track should be set up to reflect the log image. This will allow for the digital output to be corrected or straightened.

Set the Depth Axis by picking the top point of the log track. This is done using the first mode icon, Point Definition Mode. Then enter the top depth value in the box that appears.
Set the bottom point of the Depth axis by picking the bottom point on the track. Then enter the bottom depth value.
Warp the axis to match the image by placing control points along the axis. This is done using the second mode icon.