An object is initially positioned at a distance \(d_o = 3f\) to the left of a thin converging lens of focal length \(f\), forming a focused real image on a screen at a distance \(d_i\) to the right of the lens. The lens is then moved closer to the object so that the new object distance is \(d_o' = 1.5f\). If the screen is repositioned to keep the image in focus, which of the following correctly compares the new image distance \(d_i'\) to the original image distance \(d_i\) and provides the correct physical reasoning?