The opposite of "are within view" is "out of sight." This phrase implies that the object or person being referred to is not visible, whether because it is blocked by something or because it is too far away. Other antonyms for "are within view" could be "hidden," "concealed," or "obscured." These words suggest that the thing being referred to is intentionally or unintentionally hiding or shielding itself from view. Conversely, synonyms for "are within view" include "visible," "apparent," and "evident," all of which suggest that the object or person is clear and easy to see.