Mist

I grabbed this shot while on holiday in Northumberland.
The river near where we were staying was quite near the coast and it had these adolescent swans constantly patrolling right in front of me.
It was a very humid day, and each time the cold wind blew in from the sea a quite ethereal looking mist would appear almost hiding the swans.

I took this at 1/800th and F22 with two stops of underexposure so that I didn't burn out their white feathers.