The base material for the study can be accessed via the links below the images. It includes:

• Details of film development: dilution, time, temperature

• effective sensitivity (ISO) and the mean slope

• density curves and local slope (->details)

• Microscopic images of the central area of the Siemens stars (80 LP/mm)

• Microscopic images of the 8 LP/mm area of the Siemens stars

• Microscopic images of the grain structure, area of macroscopic constant optical density D=1