Damned if I can think of any use for the word. An X-ray would be one special example.
Perhaps other froms of radiation could be used to produce image.

akiagraph
n.
5Gr skia, shadow (see SHINE) + 3GRAPH6 RADIOGRAPH Also ski$a[gram# 73gram#8
ski[ag[ra[phy 7skj ag4r! fc8
n.

Some times photographers will take paper and overlay it with leaves or some such thing and expose it directly to light, then develop the resulting image. The leaf will let a little light through it so you don't get just a silhouette. Don't know what they call the process; skiagraphy doesn't ring a bell. Almost all the googles say something about x-rays.