- Digital Charts of Lough Corrib


Go to content

Dr Depth Shoreline Tutorial

How the Chart is made

The shoreline is simply a contour, the 0ft or 0m contour. The lake bed inevitably slopes up to it, either sharply, or gently. Whatever it does, we get as close as we can when we take our soundings, and leave the rest to Dr Depth to interpolate. This way we end up with a pretty accurate idea of the nature of the shoreline.

Software needed for this exercise:

  • GPSMapedit - You'll need a registered version, very good value for money
  • GlobalMapper - Not cheap software, but is REALLY useful .
  • Dr. Depth

Create your shoreline in GPSMapedit using Google maps. Correct the shoreline's position (see tutorial). Save it in MP format

Open Globalmapper and open the mp file you have just created

Click 'Edit' => 'Select all objects', then right-click on one of the selected lines and select 'Advanced feature creation options' => 'Create point features spaced along selected feature'

Sample features at 2m intervals (this stops Dr Depth interpolating through the gaps between)

Let it do its rapid work, then go to 'Tools' => 'Control Centre' and uncheck the mp file - leaving only the “user created features” checked

Now export the file as a shapefile, selecting to export “points”. You have the option to select the area you want to export on the “export bounds” if you need to

Open Dr Depth File. Import/Convert and select your shapefile. It will be converted and saved as a Dr Depth file. Now open the converted file. You now have a shoreline and all the islands etc.

Load in your tracks (or database) and let Dr Depth do its stuff

I use a custom colour file to see my 5ft (shallows) and 10ft (caution) areas in what is more or less chart format

The finished chart running in the chartplotter 'OpenCPN'

Back to content | Back to main menu