What is a photogram most similar to?

A photogram is most similar to an X-ray because both techniques result in images created by the exposure of light-sensitive materials, but they do so in different contexts. In a photogram, objects are placed directly onto a photosensitive surface, typically photographic paper, and then exposed to light. The areas that are blocked by the objects appear darker, while the exposed areas appear lighter, resulting in a silhouette-like image.

Similarly, X-rays produce images by passing radiation through objects (such as the human body) onto a detection surface; denser materials block the X-rays and appear white, while less dense materials allow the rays to pass through and appear darker. Both methods create images based on the interaction between materials and a form of energy—light in the case of photograms and radiation for X-rays.

This similarity lies in how both techniques depend on the physical properties of the materials they are working with to produce a visual representation.