If you need to position the camera there, the easiest way to do it is with lerp:
Camera set x to lerp(Obj1.x, Obj2.x, 0.5)
Camera set y to lerp(Obj1.y, Obj2.y, 0.5)
With more than 2 objects it's trickier. You can use the method in this demo, position the camera in the center of green rectangle.