Höyrypakettien

Höyrypakettien, a Finnish term, translates to "steam packets" and refers to a specific type of early photographic material. These were small, often rectangular or square, glass plates that had been coated with a light-sensitive emulsion. The emulsion typically contained silver halides suspended in a gelatin medium. The "steam" aspect of the name is believed to relate to the historical methods of preparing these plates, which might have involved steam or vapor during the drying or processing stages, though precise details can vary depending on the era and specific manufacturer.

These plates were used in early cameras to capture images. Unlike modern film, they were rigid and brittle, requiring careful handling. The resulting negatives were also on glass, and prints were made by contact printing or by using an enlarger if the technology was available. Höyrypakettien were a significant development in photography, allowing for sharper images and greater sensitivity compared to earlier wet-plate collodion processes, which required immediate development after exposure. They played a crucial role in the widespread adoption of photography in the late 19th and early 20th centuries before being largely superseded by flexible roll film. Collectors and historians of photography sometimes seek out these original glass plates.