I believe I have linked to these before, but can't find it; and now there are new photographs.
The blog post, with examples, and some clues as to how these photos were made, and more illustrations here. An example of what I'm talking about is in the advertisement below.
The blog post, with examples, and some clues as to how these photos were made, and more illustrations here. An example of what I'm talking about is in the advertisement below.