Yeah, Dawn will help, as will several commericial equivalents, some of which may be repackaged Dawn. But they also tend to compromise the optics slightly. This happens because the added layer doesn't function like another lens coating. Instead it tends to scatter light.
Other than not breathing on your binoculars, the best solution is to buy binoculars with a built-in moisture-resistant lens coating. Some older coatings had the same disadvantage as Dawn or other liquid coatings, but the recent built-in coatings don't compromise the view, since they're engineered to work with the other lens coatings. Bushnell's Rainguard is a good example.
Mule Deer,
How would classify Rain-X? More in the Dawn or in the Rainguard camp?
