Lumen prints are created by exposing ordinary photographic printing paper to sunlight for extended periods of time, creating a visible latent image. The exact colors in the image are dependent on the brand of paper and the amount of moisture involved in the print's creation.
Since fixing the paper removes or drastically alters the color, original prints are not archival. All my lumens are scanned immediately after exposure. Some are then fixed, and scanned again, but most papers don't respond well to fixing. Only a few brands remain colorful and vibrant after fixer. In most cases, the original paper serves as a transitory, intermediate stage in the image making process. Generally, I only perform minor digital clean-up and correction.