Foam on water surface, Saranac River, NY, ca.2000. Shot from a bridge looking straight down at the foam drifting by. Digital, Canon PowerShot A630. C&C welcome.
Thanks classic, good points. This is the Saranac River, it originates at Saranac Lake. It is a well known trout-fishing stream. There are no industries along its route to Lake Champlain, just a few small villages. There are white water stretches and a couple of small dam spillways, that might account for the foam.It is interesting that such methods are/were used in research laboratories to take info on the flow in water streams. Nowadays they try to use digital simulation that is faster and less costly than the physical models, nevertheless the physical models can give a better idea of the physical reality.
By the way, not sure if that foam is "innocent" for the river's life