The Photo-Engraving Process is a computer-based method for transferring image data onto sheet materials by means of milling technology. First an image template is scanned and converted into 256 gray scales. In order to transfer the image onto the sheet material, a machining file is generated from the identified gray values, whereby the file includes milling commands for a CNC milling machine. The milled module is used as master for casting the elastic RECKLI-Photo-Engraving formliners. Their elasticity, quality and reusability contribute to the aesthetics and the economic efficiency of the whole process and make it possible to recreate the image onto the concrete surface.