It is essential for good work that the camera should be provided with what termed a "swing back." This that the bick of the camera which receives the dark slide is so pivoted that it can be swung out of the vertionl position to slant either backwards or forwards. In landscape photography this provision is often of value, as it enables a better general focus to be secured, but ite chief use is when photographing buildings and for such work it is abso-lately essential. It frequently happens that in order to include the whole of a building from a particular standpoint, the camer has to be pointed upwards,.|and the movement at once throws the back out of the perpendicular. The swing back, however, enables the vertical position to be regained without moving the camera asa whole. The rule is that
Text read from the printed page and cleaned; old type leaves the occasional error.