Poster on drying board
After lining, the poster was allowed to dry completely. It was then rehumidified and temporarily mounted on a drying board. Again, experience is required. If the paper is too wet or too dry, or not evenly humidified, it can tear as it dries. The temporary mount gently and evenly flattens the poster ready for its final mount. It also supports the poster, which helps if infilling of losses and retouching are required, as in this case.