Georgian Bay is covered at large scale by the Lake Huron ‘Coastal’ scale NOAA chart included with EarthNC Plus and EarthNC Raster Great Lakes.
This chart does not have the same level of detail as the Canadian Charts within the bay, but does offer major navigation features such as buoys, markers, lights, depths, and commercial routes.
Click HERE for a screen shot of the Bay with chart loaded. For a more zoomed in view, HERE is a screen shot of the Bay entrance near Tobermory with depths and rocks visible.