Results obtained from characterizing the capabilities of a collimated cerium bromide (CeBr3) detector developed for use on robotic platforms are reported. The detector’s field-of-view is collimated by a lead slit, and experiments have been performed with point radiation sources configured in a-priori known geometric scenarios. The collimated detector is scanned over radiation sources using gimbal control, acquiring a spectrum at each angle to obtain energy-resolved angular responses. These responses are then approximated by mathematical transforms to enhance localization accuracy. Various combinations of radionuclides have been used to demonstrate the effectiveness of this approach. The results reveal that expressing X-ray and [Formula: see text]-ray angular responses with an appropriate transform improves the resolving power of the slit collimator. This technique offers distinct advantages in robot deployments by enabling additional in-situ characterization capabilities without imposing additional limitations or requirements.