A Binocular Cue is mainly based off the topic of depth perception, and how everyone is able to view certain things differently. The first type is called binocular disparity; which can be described as the various angles we can view an object. If something is farther away in distance from you, the item or object appears similar. Except when placed closer to you your vision and eyes to distinguish the difference becomes more difficult. Another type of Binocular Cue is referred as convergence which is commonly explained by when the object is closer to you it results in your eye having to move towards and into one another to keep complete clarity and focus on the object in front of you.
Example:
The two water bottles in this picture below are placed in two different spots that created depth, which will change your prospective on which ever water bottle you are keeping your focus on causing your eyes to move in or out.