DrDepth is no longer available for sale to new customers, so this is basically a note of how things used to be, before it became unavailable. I now use Reefmaster software for generating new charts and am happy to suggest using it as an upgrade to DrDepth (a free trial is available).
DrDepth was really designed to be used afloat, giving a real time picture in 2D or 3D to supplement your Navionics or CMap setup. However I never liked running a laptop in a small boat that quite often gets a hammering if the sea picks up, and just recorded data for use ashore. This allowed me to create images of the maps (usually jpegs) which I could display on my sonar if required.
I use a Lowrance LCX112C combined chartplotter and sonar which has a 10″ screen and two SD sockets to take memory cards. One of these sockets is taken up with a Navionics chart card and the other with a 2Gb memory card for recording information and holding images and other data. The Lowrance unit allows you to record a full copy of your sonar data to a logfile (Lowrance’s own .SLG files, although most other major manufacturers have their own equivalents) and to replay it later on the sonar or on a PC, and it’s this information that DrDepth uses.
The examples below are drawn from my own data and show how the software can help display more detail than an average chart, and illustrate the general size and orientation of wrecks and other features. Simply relying on sonar displays alone can be highly misleading as you turn and vary speed, and you can quickly lose perspective of what the seabed actually looks like. DrDepth basically restores that broad context and helps suggest areas to examine in more detail.
A small feature like a wreck can be mapped in 15-20 minutes, whilst other maps are built up over years by adding a new sonar track on every visit to locations such as Loch Etive. Data can be added and modified over a period of time to gradually build a larger and more accurate chart of quite large areas.
Maps created by DrDepth can be embedded in Google Earth, with a little work. The quality of Google Earth data is a bit variable, but it can work quite nicely, to allow the Drdepth maps to be seen in context. The examples below are from Loch Etive.