If you have a Hotmaps Platinum chip with a valid subscription you should update your cards! The new SonarCharts Shading has been added.
With the different shades of blue they applied it really brings a lake with the shading to life and makes picking out areas much easier.
Platinum+ Chips will be getting the update soon.
Also if you’re cards yearly subscription has run out, this is the best time to renew or purchase the Platinum+ or Hotmaps Platinum as they are $30 off for the month of May. The link below will bring you to the chart installer to update/renew.
For more information on SonarCharts Shading:
SonarCharts Shading Information