Laboratory target detection experiments are widely used to assess camouflage techniques for effectiveness in the field. There has been some research to suggest that, in maritime environments, target detection in the laboratory (photosimulation) differs from field observations. This difference suggested that the dynamic nature of real world search tasks, not represented in still images, could be a critical element in field detection. To explore the effect of dynamic elements for inclusion in laboratory experiments, we have initiated a series of studies including videosimulation. In this paper, we extend our previous work, exploring the link between field observations, photosimulation and videosimulation using data obtained at a field trial conducted in Darwin (Australia) with small boat targets. Both laboratory-based experiments (photo- and video-simulation) presented the stimuli on an EIZO colour calibrated monitor, and a Tobii eye tracker was used to record eye movements. Comparing probability of detection (Pd) from the field observations and videosimulation experiment yielded a Pearson correlation coefficient (PCC) of 0.43 and mean absolute error (MAE) of 0.23 from the identity function, whereas comparing the field observations to photosimulation yielded a PCC of 0.45 and MAE 0.20. These new results show the opposite trend to that reported in Culpepper et al 2015. That is, the new results show the laboratory experiments to be mostly easier than the field observations, whereas our 2015 results showed that field observations were easier than photosimulation.
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