Birds distance vision?

Question

How do birds discern the distance to an object? Owls look like they have binocular vision but most birds appear to be able to look at an object with only one eye at a time.

Answer 1

http://www.americaswetlandresources.com/wildlife_ecology/plants_animals_ecology/animals/mammals/whohasgoodvision.html

Answer 2

Owls have excellent binocular vision.

Most birds have some degree of binocular vision, but it is greatly reduced. They get a larger field of view though, but with less forward vision. Some bird eyes have 2 foveas, or pits, in the back of the eye where the focus is sharpest - with one fovea in a spot for forward vision, and another for sideways vision.

Answer 3

owls don't have binocular vision, owls have very bad vision, when you see them bob and weave their heads they are actually listening.