This related to the "Zero Line" card delivered software with, allows, from registrations to trace on the water, to create its own bathymetry and the mapping of the seabed.
This very rich in detail mapping can then be operated on your Humminbird and improved gradually and to measure outputs.
The data are private but can be shared with people using a combined Humminbird having acquired the "Zéro Line" card.
This version of the Autochart software allows in addition to getting a visualization of the hardness of the Fund and an overlay of the image Side Imaging.
Strong points: