 The paper compares the accuracy of participants identifying valleys and ridges in satellite images and shaded relief maps, SRMs, with different depth cues, including shadow, texture and color. The results show that the presence of texture and color significantly affects 3D shape perception, but the strongest illusion is experienced with SRMs, where accuracy is only 2%. The authors suggest that participants who are able to bypass the illusion may be interpreting photographic information consciously or subconsciously, and provide exploratory analyses of expertise, global convexity bias, and by stable perception. This article was authored by Azucultakin and Julian Byland.