552 AutoCAD and Its Applications—Advanced Copyright Goodheart-Willcox Co., Inc. guide you. Selecting the grip on the target allows the target to be repositioned. Again, use the preview in the Camera Preview window as a guide. The grip at the midpoint between the camera and target can be used to reposition the camera and target at the same time. If you pick and move one of the arrow grips on the end of the fi eld of view, the lens focal length and fi eld of view are changed. Camera Clipping Planes Clipping planes allow you to suppress objects in the foreground or background of your scene. Picture these clipping planes as fl at, 2D objects perpendicular to the line of sight that can be moved closer to or farther from the viewer. Only the objects between the front and back clipping planes and within the fi eld of view are seen in the camera view. This is helpful for eliminating walls, roofs, or any other clutter that may take away from the focus of the scene. Clipping planes can be set while creating the camera or later using the Properties palette. Clipping planes can be adjusted using grips. To set the clipping planes while creating the camera, enter the Clipping option. You are prompted: Enable front clipping plane? [Yes/No] No: To enable the front clipping plane, select Yes. You are then asked to specify the offset from the target plane. The target plane is described next. Once you enter the offset, or if you answer No, you are prompted: Enable back clipping plane? [Yes/No] No: To enable the back clipping plane, select Yes and then specify the offset from the target plane. The target plane is the 2D plane that is perpendicular to the line of sight and passing through the camera’s target point. Offsets for both front and back clipping planes are from this plane. Positive values place the clipping planes between the camera and the target plane. Negative values place the planes on the opposite side of the target plane from the camera. You can place the clipping planes anywhere in the scene from the camera location to infi nity. You cannot, however, place the back clip- ping plane between the front clipping plane and the camera. The best way to adjust clipping planes is using the Properties palette or grips. Create the camera and then display a plan view of the camera and target (an approxi- mate plan view is okay). Select the camera and open the Properties palette. In the Clipping category, select the Clipping property. In the property drop-down list, select Front on, Back on, or Front and back on to turn on the appropriate clipping plane(s). Notice that the clipping planes are visible in the viewport, Figure 21-3. Next, enter Select the visual style Figure 21-2. The Camera Preview window is displayed, by default, when a camera is selected.