I have the older Humminbird 565 and I am constantly adjusting the speed when I go from the outboard to trolling motor and was curious is there was a relation from how fast on boat speed versus depthfinder scroll speed. Mine is measure in percents and I would like to get a get "read" to show how far apart the structure is when it comes on the screen. I may be overthinking this but it was a question I had to ask. Thanks for the replies. Rollcaster....................................