One of the greatest learning tools in these units is the recording feature...

When I first started using my unit...
I would fish until 1 hour before dark...
Then I would motor to a spot down the bank from my launch site (about 1/4 mile)
Turn my unit to "Record" and troll at a constant speed all the way down the bank back to the launch site...
Stop the recording at my launch site...
Take the recording home...
Take my unit in the house...
Replay my recording on the unit (and in Humviewer)
Study the recording without fishing distractions...

I found it much easier to learn SI image interpretation from a recording than trying to learn and fish and control the boat at the same time...

Rickie