The Deviation Probe DevProbe1 is used to measure the borehole deviation. A three-axis magnetometer measures the azimuthal direction of the borehole and a dual tilt sensor provides information about the inclination. The probe is sealed and temperature compensated. Borehole deviation is required to determine the precise XYZ location of a seismic source or geophone inside a borehole. A software is provided to visualize and store the deviation data.