A blue photographic proof used to check position of all image elements.
Blueline is a brand of photographic paper that is used for making blueprints and other technical drawings. It is a very thin paper that is coated with a light-sensitive chemical. When exposed to light, the paper turns blue.
The paper is used in a process called contact printing. A negative or positive image is placed on top of the paper and exposed to light. The exposed areas of the paper turn blue, while the unexposed areas remain white.
A blue line, in the context of photography, is a type of film or paper that is used to produce blueprints. The blue line is a negative of the original image, and it is used to create a positive copy on white paper. This process is known as blueprinting.
The blue line is created by first exposing the film or paper to light. This is typically done using a contact print, which is made by placing the negative in direct contact with the paper. The film or paper is then developed, which causes the exposed areas to turn blue. The darker the original image, the darker the blue line will be.
Once the blue line is developed, it can be used to create a positive copy. This is typically done by shining light through the negative and onto the paper. The light will cause the exposed areas to turn white, while the non-exposed areas will remain blue.
Blueprinting is commonly used in the construction industry, as it allows architects and engineers to create detailed plans and drawings of buildings. It can also be used for artwork, to create copies of paintings or other images.
While digital photography has made the process of creating images much easier, there are still many photographers who prefer the Blueline process for its control and quality. This process can produce prints that are far superior to those made with a digital camera, and it allows the photographer to create unique images that cannot be replicated with digital technology.