How modern fish finders incorporate GPS-driven mapping technology

Modern sonar devices have enormous capacity – both in terms of producing detailed subsurface images and offering up-to-date and precise maps and charts for anglers.

Maps and charts – with personally saved hot spots or way points – are no longer secret weapons, but a standard part of the fishing arsenal of most boat or kayak fishermen or women.

In this article we break down some key mapping innovations starting with the technology that makes it all possible – GPS, or global positioning system.

GPS technology came into sonar devices from the early 2000s and now almost all units have GPS functionality adding chartplotting and mapping capability to the sonar capability of the fish finder.

It’s proven a powerful combination. Combining the ability to navigate to the best spots and drop way points, while having good insight into the structure and fish life below, gives fish finder users a powerful advantage on the water.

Combined with downloadable charts and SD cards, users have the ability to install high-quality charts of their favourite waters on to their fishfinder with little trouble.

Here below we have summarised the latest mapping technology powering the three leading recreation fish finder brands – Lowrance, Humminbird and Garmin.

Lowrance’s C-MAP Genesis system

What’s better than an up-to-date chart? One that keeps updating all the time. This technology uses data from other Lowrance users to generate a “social” chart that provides a detailed and accurate view of previously uncharted waters. It also allows you to create your own detailed maps to save and/or share to the broader community of users. More information can be found here: https://www.genesismaps.com/ And here: https://www.lowrance.com/en-au/lowrance/type/mapping/c-map/c-map-genesis/

Humminbird’s Autochart Live

AutoChart live allows Humminbird users to create their own detailed maps with depth and bottom contours that can be used and viewed on the fish finder or saved and viewed on a computer to reveal more detail. With an i-Pilot link to your trolling motor, you can follow a contour line to fish at a particular depth using your boat or kayak.

Garmin’s GPSMAP system

Garmin is a new player in the fish finder market, but it has its own self-mapping feature called GPSMAP where the unit generates and saves its own maps of the waters you are fishing. These can be used by the unit or saved for later use.

Kayak fish finders

Fish finders for kayaks tend to be on the simpler and smaller in size models and often cost less than $1000. But these days Lowrance, which is arguably the preferred choice for most kayak fishers, has the Genesis Live mapping features on its base model the Hook Reveal. We use a Hook Reveal on our kayaks and its simple to use yet powerful and now comes with Lowrance’s FishReveal technology – it’s our standout choice as a kayak fish finder in the five-inch or (preferably) seven-inch size.

Mapping functions are now available as standard even in the smaller models of fish finder suitable for kayaks and we use ours extensively to save and share marks where we have caught fish or found useful structure.

Fish finder set up

As we have the small screen models on our kayaks (four-inch and five-inch) we tend not to use the split screen, but for larger screen models many people will run the mapping/chartplotting function in one panel and conventional sonar and/or structure downscan on the other portions of the screen. For models with side scan, often the preferred set up is to run that along the bottom of the screen. For further information on how fish finders work and how to read fish finder images please check out our comprehensive post on this topic.

Rick Wallace, editor of Tackle Village