As described in Chapter 6, the skeleton is divided into axial and appendicular portions (see Figures 6.1 and 7.1). The axial skeleton is structured from 80 bones segregated intothree major regions: the skull, vertebral column, and thoraciccage (Figure 7.1) . This part of the skeleton (1) forms the lon-gitudinal axis of the body, (2) supports the head, neck, and Chapter 7 The Skeleton 199 7 Figure 7.1 The human skeleton.
Above: Some cameras have a switch to set it to auto or manual focus. Manual focus, meanwhile, disables autofocus and enables you to adjust it yourself. This is useful when the focusing system can't find focus for whatever reason, such as when it's too dark or when there's little contrast in the scene.
1 The focus chart is located right across from the camera. 2  The distance between the camera and the wall depends on the focal length of the lens you are testing. 3  If you are using a 50mm f/1.4 lens, then the distance between the camera and the test chart should be approximately 5 to 7 feet (1.5-2 meters).hen testing the autofocus accuracy of a camera or lens, it is always best to have exposure consistency. Therefore, I recommend switching to Manual mode and keeping the same exposure for each shot. Here is a summary of what I would recommend in terms of camera setup: 1  Switch your camera to full Manual Mode.