Caterina Rebecchi (asker) Dec 8, 2009:

Grazie mille, Claudio. I tuoi interventi sono sempre preziosi. Il libro, per giunta, è scritto da un autore americano.

claudiocambon Dec 8, 2009:

not a term used by photographers As a photographer who uses a fair amount of lighting, I can tell you that in 20 years of work I have NEVER heard this term. Perhaps the Brits use it, and perhaps the movie industry uses it, but it's not used in still photography the US. The closest term might be something along the lines of a focusing lamp or light, although that begins to be ambiguous, as it can also refer to a bright light you turn on only to focus on a scene before shooting just to make sure your focus is on. I realize there's not necessarily that much you can do about your text, but just so you know.