This document is the final report on the work carried out to fulfill the second and last part (2.1-2.6) of the Statement of Work for the ESTEC purchase order # 151713 of 05/10/1995. This document describes the work performed according to the following statement of work items: 2 Dual Optical Head Configuration 2.1 The current DTU SIM will be equipped with a dual head fixed to a common reference frame. 2.2 The angle between heads shall be optimized in terms of accuracy, avoidance of blinding and occultation, and sky coverage. The typical orbit type chosen to perform this trade off will be low earth (say, 500-800 km altitude), nearly circular (eccentricity smaller than 0.05), near polar (sun synchronous is a good choice). 2.3 The quality of transition from one head to another or from dual to single head sensing shall be investigated, experimentally and analytically. 2.4 The capability to provide calibrations shall be studied. 2.5 Indications will be given about dependence of performance on integration time and on computing time. 2.6 A report shall be provided.The work reported on in this document will answer the above topics in the order they are dealt with scientifically, and will only be summarized in the conclusion in the order of appearance in the Statement of Work. This work relies upon the work described in the previous report "Real sky performance of a single head version", hence for discussions of noise and precision definitions, please refer that work.