I often find it useful to consider landscape images as comprising three areas, foreground, middle-ground and background. While our human perception tends to focus more on foreground details and objects in our near vicinity, the camera makes no such distinctions. Foreground rocks that the photographer could reach out and touch while at the scene are rendered with the same presence as distant clouds in the final image. When visualising, I think it pays to try to see background and foreground details with equal importance.