[nickloewen]

Fantastic!

The comment you're replying to sent me looking for references, too. The closest I found was this article, which mentions an installation at RAF Truleigh Hill: https://www.shorehambysea.com/raf-truleigh-hill/

"This device was a continuous photographic process which filmed the radar screen, processed the film and projected the image onto a glass screen within a very few seconds."

(I wonder whether something like the Eidophor system that NASA used for mission control would have been another option? https://en.wikipedia.org/wiki/Eidophor)

[masswerk]

Regarding the Eidophor and possible similar technology in WWII, it may have been that there was still something missing to make rapidly spinning mirrors (like in laser printers, etc.) a viable option.

That article on RAF Truleigh Hill is a great link, BTW!