Reflectance Transformation Imaging (RTI) was another method used to study Saint George. By shining a light source on the painting at an angle, it reveals raised areas called pastiglia. Crivelli built them up in gesso before applying paint and gold leaf. Look closer at the knight’s armor and chainmail; modeled in gesso then painted and gilded, they catch the light and give the warrior’s figure greater weight and presence.

Here, decoration on the horse's bridle shows its meticulous three-dimensional detail when raking light is applied.