You all know that harsh Sun of summer in Rome was a problem during the filming of To Rome with Love so to battle it and create the desired lighting, Darius Khondji and his team used diffusion balloons from ALF Service in Milan. This is how that looked like in Piazza della Madonna dei Monti:
They remind me of inflatable air mattresses, that swimming pool/beach toy that, I see now, has a few other names in different varieties of English.
I was wondering has anything like this been used elsewhere and how fairly standard is it as a piece of equipment?