A wildlife photographer uses a moderate telephoto lens of focal length 135 mm and maximum aperture f/4.00 to photograph a bear that is 12.0m away. Assume the wavelength is 550 nm.
A). What is the width of the smallest feature on the bear that this lens can resolve if it is opened to its maximum aperture?
B).If, to gain depth of field, the photographer stops the lens down to f /22.0, what would be the width of the smallest resolvable feature on the bear?