Acuros® CQD® SWIR Camera Applications Note - High Resolution Infrared Reflectography of Painting Underdrawings

Infrared reflectography of paintings is used to make underlying layers clearly visible in contrast. IR radiation penetrates the upper layers of the painting and is reflected by the primer. The underdrawing, which is made with carbonaceous colorants on the primer, absorbs IR radiation and shows a strong contrast. The 2 MP sensor of the camera in combination with a lens with a short minimum working distance allows the realization of a very high resolution, which is important for the possibility to evaluate the underdrawing. The effective achievable resolution is therefore dependent on both components, sensor and lens.