Filter wheel (a.k.a. Italiana)
The filter wheel system "Italiana" (simply called "Italian wheel"), manufactured in Italy for the Brera Observatory, has two filter wheels, one with ten filter positions and another with nine (including one position for a polarizer). Usually, the filters are fixed and therefore are not interchangeable with other available in the observatory. This instrument is installed only on the 2.1m telescope.
Documents (Spanish version only):