I have a hummingbird 798. I just traded the compact puck for the HD SI transducer. My question is: what do I need in order to create my own lake maps from scratch? I fish a lot of private lakes in PA that have no maps. Who can help? Thanks!

Check TW for the Navionic system. Brian.

Navionics can do that for you.

The program is called Sonar Charts. You get that with the Navionics+ map card. That is for Nautical Charts and Sonar Charts.

You record on a blank formatted memory card and upload the recordings (sonar logs) to the Navionics Sonar Charts servier.

After your data is processed, you get an email letting you know it is done and you can download the map/s.

It is a FREE service, you just buy a map card to download the Navionics maps to.

It is shared data and can be viewed on the Navionics web site's Web App and anyone can get your maps by doing an update with their Navionics+ or Navionics Hotmaps Platinum card.

The Navionics+ product comes with no maps, you choose what locations to download to the map card from anywhere in the country. You can have one lake, a dozen lakes or hundreds of lakes up to the card capacity of 2GB. It is updateable for a year.

I have submitted over 200 sonar logs for that program.

 

There is also Lakemaster Auto Charts that is done the same way, but you purchase the computer software to process your recording/s yourself and it is yours only.

 

This is one lake I did that had no maps of any kind, not even an outline on the Navionics Nautical Charts.

 

This is what I had before Sonar Charts, just land with my GPS waypoints:

 

 

This is what Sonar Charts produced with lots of recording. The lake is 420 acres and is electric-only:

 

 

 

Note the GPS location is the same in both pictures.

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