Contributions to the evaluation of observability performance in difficult ambient conditions, for observation equipment during night and day

The purpose of this paper is to establish an evaluation method of the observability performance for equipment that enables day and night vision (using thermal cameras, gated image intensification and CCD cameras using L3V based on e2v technology). This is done by modelling of experimental results of simulation setup in the lab. Starting from the predictive evaluation procedures of the observation, the paper analyses the relevance of method to establish the limits in the utilization of the above- mentioned equipment, from the point of view of the observation probability, in difficult ambient conditions, such as reduced illumination level or aerosol curtains. Moreover, the present work compares subjective factors that can influence the prediction by the participants on the experiments (age, training, decision time) and objective factors (contrast between background and image, resolution of the observation system and image noise).