I research a lot of photographs for college chemistry textbooks. My new favorite images are atomic force micrographs (AFM for short). An AFM provides a 3D profile of the surface on a nanoscale, by measuring the force between a sharp probe and surface at very short distance. The probe is supported on a flexible cantilever. The AFM tip “gently” touches the surface and records the small force between the probe and the surface. Above are two examples from Oxford Scientific.