I have a query on the following images and the 'negatives' associated with them? They seem to be some type of copy of the prints but I'm stumped as to the purpose and how these may have been made.
The 'negatives' are all different sizes and have no product markings or identifying notches. They sometimes contain the edges of other images as if the whole was a much larger sheet and on one there is a section that looks as if an exposure test has been made with gradually lightening stripes. There are also finger marks on the 'negatives' that look more than what would have been left by normal handling -rather like a normal film negative would be if handled when wet.
The edges of the images are defined by a heavy almost (but not quite) opaque dark red tape which is now degrading and becoming sticky.
Image subjects vary from what look to be book pages, magazine articles and photographic prints.
There are sometimes corresponding prints on a metallic gold or silver faced paper - the rear of the paper is white and it is thinner than a conventional photographic paper. The prints seem to be a mix of sizes, exactly the same as the 'negative' or sometimes bigger.
They come with no record of who or when they were donated to the archive but this is likely to be before the mid 1980s.
Before I handled them I presumed they were just inverted & photocopied onto acetate but upon examination they seem to be much finer grained and without the density of ink sitting on the reverse (mat) side that such copies would have. The medium itself also seems thicker and more like a neg to handle, but there may be photo-copiers out there that can output to this quality I don't know.
I am presuming some sort of commercial copy process but have no idea what this would be.
Anyone got any ideas??