The image size is smaller than the object size, the objects in the mirror appear to be farther than they actually are. This can cause the viewer to assume the car behind him might be farther than it is. Convex mirrors make objects seem to appear smaller than they are in reality, which allows for a wider viewpoint in a smaller space. This is one advantage of using a convex mirror. The disadvantage is that convex mirror is that they make it appear like those objects are at a more noteworthy distance than they actually are. It always gives a virtual, erect and a diminished image.