Since the lakes are frozen I spent time this weekend getting to know the Deeper Pro sonar sensor better as well as the river cam.
I spent about an hour and a half all told mapping out a 200 yard stretch of the river. The GPS went a little haywire under the bridge but then that's to be expected as solid concrete doesn't help with the signal, however the rest of it was fairly straightforward.
I used the wide beam for speed as all I wanted was the contours and the practice.
Not a bad few hours work and the more I practice with it, the better i'll get.