Abstract: A method of deconvolving the far-spaced detector response of a dual-spaced neutron logging tool, coupled with dynamic matching of the near-spaced detector response, improves the vertical resolution of the tool's formation porosity measurements. Near/far ratio processing and the standard shop calibration procedure are retained to continue to provide accurate, borehole compensated formation porosity measurements.

Abstract: An electrical feedthrough connector is illustrated for use in down hole sondes and other logging tools exposed to pressures of up to 25,000 psi and temperatures of 500.degree. F. It incorporates an elongate conductive metal pin surrounded by a concentric sleeve of insulative material and on the exterior of that, there is an elongate metal clad sleeve. This defines the structure so that the feedthrough can be mechanically anchored on a bulk head. In addition, at the end exposed to high pressure, the central conductor is totally covered by an elongate insulative sleeve. On the exterior of that, there is an elongate all encompassing resilient boot which extends substantially up the length of cable connected with the feedthrough connector but which is in contact only with surfaces which are insulated from the central conductor. This boot is formed of resilient rubber like material and is capable of deforming. It excludes the intrusion of fluids in the well borehole environment where the device is used.