Photogrammetry is the method of making measurements from photographs where you can gain enough information to create a 3D object. With the right tools and workflow, you can create 3D models just from photographic references!
John Haverkamp leads you through a high value tutorial from taking good photos, to creating a mesh, editing in ZBrush and importing the model ready for use in Daz Studio.
In this case study he utilizes multiple photographs of a forest floor rock, complete with its detailed texturing. John turns this into a Daz Studio 3D asset, using Meshroom and ZBrush.