Dotsie wrote:There seem to be a number of black ribboners who can go out in daylight, maybe it's being off the red stuff that does it. Isn't Otto fine as long as the salamanders don't go off?
Otto occasionally is described as standing under a sunshade.
Ankh-Morpork also has a lot of fog, mist, and general air pollution, being an early industrial city. Possibly the trolls and vampires don't need to use much protection in a city where you can only tell it's spring because the birds are coughing in rhythm and the slime on the river is a brighter shade of green.