Panoramic Infrared Reflectography (PIRR)
Panoramic Infrared Reflectography (PIRR) is a valid alternative to the much more expensive scanners for Infrared Reflectography (IRR) which is the imaging of works of art with a scientific camera in the range 1000- 1700 nm or further. Pigments such as azurite, Prussian blue and malachite become transparent only in the far infrared at about 1500 nm. The PIRR method consists of taking a series of images of a scene with a precision rotating head and then using panoramic software to align and stitch the shots into a single, seamless panorama. It can be implemented with consumer panoramic imaging tools, which can be upgraded following technical developments; as opposed to infrared scanners, which are products that cannot be modified. Self-assembled, modular equipment can be modified for specific tasks and upgraded with a comparatively little budget, following technical and scientific developments in the consumer market, e.g. upgrading to an InGaAs camera with higher pixel count. The stitching software is easy to use; the overall panoramic method does not require specialized personnel or intensive training and, for these reasons the method is appealing to medium‐small museums and private conservators who want to implement an affordable method to professionally document their objects.
Infrared Reflectography (IRR) makes pigments more transparent than IR photography. Though, IRR cameras have much smaller sensors so it is necessary to acquire a large number of images with the panoramic head and then stitch them together using the Panoramic stitching software.
