Writer and scholar Lauren Elkin describes the very particular grey of a rainy Paris in the time of year that the French revolutionary government called Pluviôse, the month of rain. She talks about the way a particular quality of grey sheen was captured by the French Impressionists, and with it a sense of melancholy. It's a vision that recurs in art and film, from Gustave Caillebotte's 1877 Paris Street, Rainy Day, to the recent Christophe Honore film, Les Chansons d'Amour. Elkin describes the latter as appearing to have been shot through a very realistic grey-green "Paris in the rain" filter, which gives it a power and mood rooted in its setting.