A laser method was extended and prepared for obtaining reference measurements to calibrate scale deposition thickness models for pipelines. The technique makes use of a laser device that is inserted into a pipe. Photographs of traces of laser light projected onto the internal wall of the pipe were obtained by slow‐shutter speed photography. Image processing was applied to find the shape and area of the traces. By comparison with images of a clean pipe, accurate estimations of the deposition thickness and shape can be made. The method succeeded in capturing various deposition shapes and quantifying the amount of scale present both in laboratory and field tests. The field tests were performed in a pneumatic conveying system afflicted with scaling, located in a metal production plant.