hank970
Well-Known Member
A camera sensor relies upon an analysis of pixel-to-pixel contrast to achieve focus and will probably focus on the subject with the highest contrast toward the center of the frame. It wants to focus on something, preferably a subject with contrasty edges or details that set it apart from its surroundings. If nothing in the focus box fits the bill, focus may "hunt" from near to far without ever making a solid determination. A low contrast subject in reduced light or one in which there's a lot of dull, repetitive, fine detail doesn't give a sensor much to work with.