I am new to HB with a Helix 10 SI. I would like to zoom to a specific section of the water column, not just the bottom track. ex: I am in 160 ft of water fishing for salmon, I would like to zoom into 20-50' on one half of the screen and regular sonarbon the other half of the screen. The closest to this is on pg 30-32 of the manual but not really what I want.