Four photos taken in quick succession of men wearing civilian clothing posing in a tent as a wind blows through in a Union camp during the American Civil War, c. 1864

Source

Animation of the scene is here: –

[Image source.]

https://catalog.archives.gov/id/529164

I wonder if these were intended to be [stereographs](https://www.npr.org/sections/pictureshow/2011/06/28/137450464/3-d-motion-pictures-from-the-civil-war)