Newtonian Prismatic Spectrograph B

Year: 1957
Manufacturer: Officine Galileo – Florence
Materials: Aluminum, steel, brass, optical glass
Dimensions: L = 3600 mm; P = 3600 mm; H = 600 mm; Weight: 20 kg

Built-in 1957 by the Officine Galileo in Florence, spectrograph B was designed for the Newtonian focus of the Galileo telescope, replacing the photographic camera.

The instrument includes a lens collimator, a micrometer-adjustable slit, a 60° SF2 flint glass prism and two interchangeable triple camera lenses, ensuring good definition over the entire visible spectrum between 3600 and 7000 Å. The two cameras offer linear dispersions of 132 Å/mm (Camera I) and 278 Å/mm (Camera II), optimized for different observation needs.

The spectrograph is completed by a pointing and guiding system, a fluorescent lamp for the comparison spectrum and a light conveyance system using symmetrical prisms. The solid metal structure and thermal insulation ensure precision and stability during observations.

A compact and versatile instrument, prismatic B represented an evolution in spectroscopy, contributing to detailed studies of the sky.