What are glass negatives and how do they work from years ago.
Back in the very early days of photography, long before film as we know it was invented, photographs used to be made on glass. In those days photographers often had to make their own glass photographic plates in their own home ‘laboratory’ or darkroom, by coating a light sensitive substance onto a sheet of glass which was then inserted into the back of the camera. Often the plates would be approximately the size of an A4 size sheet of paper, maybe even bigger.
After taking the photo and developing the glass plate, the photographer had to make prints from the glass negative by laying it directly in contact with photo paper under a lamp (called ‘contact’ prints). – David Barry