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 Trul

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/ 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 https://en.wikipedia.org/wiki/Eidophor)