Gelatin Dry Plate Magnification
Image Structure
Gelatin dry plate is based on the light sensitivity of silver halides. During exposure a latent image is formed, which is chemically developed. The image is composed of fine silver particles.
Gelatin dry plate is based on the light sensitivity of silver halides. During exposure a latent image is formed, which is chemically developed. The image is composed of fine silver particles.
What to look for: Continuous tone image under low magnification. Under high magnification image grain will be visible.
Under low magnification of 10x the image appears continuous in tone.
Under 30x magnification the image grain is slightly visible.
Under higher magnification of 50x the image grain is visible.
Layer Structure
Gelatin dry plates are composed of essentially two layers: gelatin on glass. To make a gelatin dry plate, the glass support had to be cleaned, polished and treated to ensure good adhesion of the gelatin to the glass. The glass could be treated in several ways: a thin coating of hardened gelatin, dilute albumen, India rubber or soluble glass could be applied, or the glass could be chemically etched. Warm liquid gelatin emulsion was then poured onto the plate in a thin and uniform layer.
Gelatin dry plates are composed of essentially two layers: gelatin on glass. To make a gelatin dry plate, the glass support had to be cleaned, polished and treated to ensure good adhesion of the gelatin to the glass. The glass could be treated in several ways: a thin coating of hardened gelatin, dilute albumen, India rubber or soluble glass could be applied, or the glass could be chemically etched. Warm liquid gelatin emulsion was then poured onto the plate in a thin and uniform layer.
What to look for: Gelatin binder on a glass support
This cross section reveals a two layer structure.