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Photo-simulation is a widely used method for target detection experimentation. In the defence context, such experiments are often developed in order to derive measures for the effectiveness of camouflage techniques in the field. This assumes that there is a strong link between photo-simulation performance and field performance. In this paper, we report on a three-stage experiment exploring that link. First, a field experiment was conducted where observers performed a search and detection task seeking vehicles in a natural environment, simultaneously with image and video capture of the scene. Next, the still images were used in a photo-simulation experiment, followed by a video-simulation experiment using the captured video. Analysis of the photo-simulation results has shown that there is moderate linear correlation between field and photo-simulation detection results (Pearson Correlation Coefficient, PCC = 0.64), but photo-simulation results only moderately fit the field observation results, with a reduced χ2 statistic of 1.996. Detectability of targets in the field was, mostly, slightly higher than in photo-simulation. Analysis of the video-simulation results using videos of stationary and moving targets has also shown moderate correlation with field observation results (PCC = 0.62), but these are a better fit with the field observation results, with a reduced x2 statistic of 1.45. However, when considering videos of moving targets and videos of stationary targets separately, there appear to be two distinct trends, with video-simulation detection results being routinely higher for moving targets than the field observation results, while for stationary targets, the video-simulation detection results are mostly lower than the field observation, similar to the trend noted in the photo-simulation results. There were too few moving target videos to confidently perform a fit, but the fit statistics for the stationary target videos becomes similar to that of the photo-simulation, having a reduced χ2 = 1.897.
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