Foffonof Depth Converter Tool


NDSF vehicles computer depth from pressure.  The best practice model for this conversions is the Foffonof model.  The Foffonof model takes latitude into account.  Older versions of NDSF code used a fixed latitude of 30 degrees.  This results in a small error of roughly up to order 0.2% as dives move away from this latitude. Sentry converted to a correct latitude model starting with Sentry 282.  Jason and Alvin will convert in the near future.  The best practice to update old data or convert new data is to use the raw pressure data (which is and has been logged by all three vehicles) to compute depth directly via the method of your choice.  In the event that you do not wish to undertake this, we are providing the tools below on an as-is where-is basis.  These tools are offered below for Windows and Linux (Tested on Ubuntu 14.04 but should work broadly) with Mac to follow soon.  The versions below are fully compiled and ready for use.  We are also making the code for this utility open source via BSD-3 license at