Videos Using Sonar Chart to Create your Own Lake Contour Maps September 13, 2019September 14, 2019 The Next Bite Gary Parsons, Lowrance, Lowrance HDS 12 Touch Gen 3 Gary Parsons shows how to create your very own lake contour maps using Lowrance Sonar Chart Live Other Related Posts: Lowrance Live Mapping and Where to Locate your Point One GPS… Lowrance Genesis Live and Why You Should Use It. Watching for Bait on Lowrance Lake Trout Ice Fishing Rod Set-Up