Change Camera Parameters
When a camera is selected from the Actor List at the top of the Document Window or the Parameters/Properties palette, you can access its parameters and properties. The parameter dials offer several additional controls that aren’t available within the Camera Controls.
Changing Perspective
Perspective gives the effect that the scene is receding into a converging point in the distance. The Perspective value is tied to the Focal Length value (or simply Focal in the Parameters palette). The focal length is the distance from the camera where the camera is in focus.
Focal Length values are measured in millimeters that correspond to lens values on cameras. Low Focal values like 24mm and 10mm represent wide-angle lenses that are good for crowds and scenery shots. At extremely low Focal and Perspective values, the scene objects can appear distorted, as shown in Figure 6-14. Higher Focal values like 85mm and 110mm represent a telephoto lens that is focused tightly on close details. The Focal and Perspective values have no effect on orthogonal cameras. The Focal Length and Perspective values can be set using the Camera Controls or the parameter dials.
To get a quick idea of how much perspective is in the current scene, look at how square the ground plane is. As a general rule, use a 110mm Focal value for head and shoulder portraits, 35mm for standard scenes and crowds of people, 28mm for scenery and landscape scenes, and 16mm for a fisheye effect.
Creating Depth of Field
A depth of field effect occurs when the camera is focused on a specific point in the scene and all other points closer or farther from this point appear blurry. The larger the distance from the focal point, the greater the amount of blur. The Focus Distance parameter lets you interactively set the focal point for the scene, by dragging a set a crosshairs about the scene.
While you’re changing the Focus Distance value, the Focal Distance Guide appears to help you position the focus point. Enable the Display, Guides, Focal Distance Guide menu to toggle this guide on.
Another parameter that impacts the depth of field effect is the F-stop. This parameter sets the size of the camera’s aperture. Cameras with a larger aperture let more light in when the image is captured. Setting the F-stop value to a low value causes the blurring for objects positioned away from the focal point to be more pronounced. Higher F-stop values reduce the blurring effect.
Another way to think of the F-stop value is as a radius that surrounds the focal point. Lower F-stop values cause only a small area around the focal point to be in focus, while larger F-stop values increase this area, enabling more of the scene to be in focus. The radius of the area in focus is also impacted by the Focal Length value that defines the range of the scene within the camera’s view. In Figure 6-15, the image on the left uses an F-stop value of 0.4 and the image on the right uses an F-stop value of 6.4. Notice how changing the F-stop value affects the depth of field effect.
To see the depth of field effect, you must enable the Depth of Field option in the Render Settings dialog box. More on the Render Settings dialog box is covered in Chapter 16, “Rendering Scenes.”
Creating a Time-Lapse Motion Blur
The Shutter Open and Shutter Close parameters can be adjusted to create a time-lapse motion blur. Motion blur causes objects in motion to be blurred as they move across the current frame. By leaving the camera shutter open longer, a value measured in frames, the scene motion becomes blurred as it moves. This is a good effect to use to show objects moving very fast, such as an airplane propeller or a speeding superhero. Figure 6-16 shows a ball object being moved rapidly in front of a figure. The image to the left has the shutter open for half a frame, but the image on the right has it open for two frames. The slower shutter results in a more extreme blur effect. The effect of these parameters is visible only when the Motion Blur render option in the Render Settings dialog box is enabled.
The motion blur effect also depends on an option in the Render Settings dialog box. More on the Render Settings dialog box is covered in Chapter 16, “Rendering Scenes.”
Setting Clipping Planes
A clipping plane is an imaginary plane that is parallel to the camera view and causes all objects closer than the Hither plane and farther than the Yon plane to be hidden. These planes can be used to hide certain objects in the scene for quicker rendering or to cut through an object to see its interior. Figure 6-17 shows the Hither plane slicing through the front of the default figure. The clipping planes only affect the Preview display, not the rendered scene.
The Hither and Yon clipping planes can be used only when the OpenGL view option is selected.
Using Camera Transform Parameters
The Dolly parameters have the effect of panning the camera from side to side. The Scale values cause the camera to zoom in and out of the scene and the Orbit values cause the camera to rotate about the scene’s center point. The Dolly and Posing cameras use Roll, Pitch, and Yaw parameters instead of Orbit because their rotations are about the camera’s center instead of a point in front of the camera.
Resetting Cameras
If the camera’s parameters throw the camera off and you lose control of your view, you can always reset the current camera by loading the default camera setting from the Library.
Use the Dolly Camera
1. Open Poser with the default figure visible.
2. From the Camera Controls pop-up menu, select Dolly Camera. Then, from the Actor List at the top of the Document Window, select the Cameras, Dolly Camera option.
3. Select Window, Parameter Dials to open the Parameters/Properties palette, if it isn’t already open.
4. Drag the Pitch dial to [ms]35, the Yaw dial to 45, the DollyZ to 2.0, the DollyY to 3.0, and the DollyX to 2.0.
Notice how the Dolly camera rotates about its own center, as shown in Figure 6-18.
5. Select File, Save As and save the file as Dolly camera view.pz3.
Resetting a Camera
1. Open Poser with the default figure visible.
2. From the Camera Controls, drag the parameter dials and the Camera Controls until nothing is visible in the Document Window.
3. Open the Library and navigate to the Camera Sets folder, and then select a non-orthogonal view and click the Apply Library Preset button.
The camera returns to a view that you can use.
Aim And Attach Cameras
In addition to the many controls, parameters, and properties available for lights and cameras, there are also controls available for making cameras point at specific items and for attaching and parenting cameras to other scene items.
Pointing Cameras at Items
You can aim cameras to point at a specific scene item. This item can be any body part, prop, light, or even another camera. To point a camera at a specific item, first select the camera using the Actor List at the top of the Document Window or the Parameters/Properties palette. Then, choose Object, Point At. The Point At dialog box, shown in Figure 6-19, appears with a hierarchical list of the scene items. Within this dialog box, select the item that you want the camera to point at and click OK.
Even though the Object Parent dialog box is used to select the point at object, the Point At command doesn’t actually parent the object as the Hierarchy Editor shows.
Once the Point At command is used, a Point At parameter appears in the Parameters palette. If you change this value to 0, the camera no longer follows the selected item. Setting the Point At value to 1 makes the camera follow the object exactly. Values between 0 and 1 cause the camera to lag behind the object. This provides an easy way to animate how closely a camera follows an object. To remove the Point At feature, select the item and the Object, Point At menu command again and choose the None button in the Point At dialog box.
Pointing Items at the Camera
In addition to having a camera follow an item, you can also do the opposite and have an item point at the camera. For most body parts, this will cause the object to rotate at askew angles, but for the eyeballs it works quite well. Figure 6-20 shows the eyeballs of the default figure set to point at the main camera. The result is that the figure is looking directly at the camera even if the camera moves.
Attaching Cameras to Items
You can attach cameras to scene items using Object, Change Parent. This menu command also opens the Object Parent dialog box, where you can choose an item to be the camera’s parent. Once attached, the camera moves along with the attached item. Parenting a camera to a body part and moving the figure causes the figure (or body part) to stand still while the scene and background move independently.
Using the Camera Dots
If you want to temporarily remember a specific camera setting for use during the current session, you can use the Camera Dots to place the current camera settings. The Camera Dots are one of the options in the Memory Dots palette, which is opened using the Window, Memory Dots menu. To remember camera settings, select the Camera Dots option from the pop-up menu at the top of the Memory Dots control, as shown in Figure 6-21, or select the Edit, Memorize, Camera menu. Clicking a dot once adds the current camera to the selected dot where you can recall it at any time by clicking the dot that holds the camera settings. Holding down the Alt [Option] key while clicking a Camera Dot clears the dot.
Poser allows a unique set of Camera Dots for every room.
Point a Camera at the Foot
1. Open Poser with the default mannequin visible.
2. Select the Main Camera item from the Actor List at the top of the Document Window.
3. With the Main Camera item selected, choose Object, Point At.
The Point At dialog box opens.
4. Select the Right Foot element in the Point At dialog box and click OK.
5. Select and move the camera about the Document Window.
Notice how the camera stays focused on the foot element as it is moved about the scene, as shown in Figure 6-22.
6. Select File, Save As and save the file as Pointing camera.pz3.
Attach a Camera
1. Open Poser with the default figure visible.
2. From the Actor List at the top of the Document Window, select the Cameras, Main Camera option.
3. With the Main Camera item selected, choose Object, Change Parent.
The Object Parent dialog box opens.
4. Select the Left Hand element in the Change Parent dialog box and click OK.
5. Select and rotate the left arm in the Document Window.
Notice how the camera changes as the left hand moves, as shown in Figure 6-23.
6. Select File, Save As and save the file as Attached camera.pz3.
Change The Background
Adding a background image or movie can often help you as you pose a figure. Imagine loading the movie of a dancer as a background. You could then animate the dance steps by matching the figure to the background movie. You can also render background images to add a nice backdrop to your scene.
Changing the Background Color
Changing the background color is accomplished easily using the color dots found at the bottom of the Document Window. There are color dots for changing the Foreground, Background, Shadow, and Ground colors. Clicking any of these dots opens a pop-up color palette where you can select a new color. You can also use the Display, Background Color, and Foreground Color menu options to change these colors. Both these menus open a color selector where you can choose a color.
Loading a Background Image
You load background images using the File, Import, Background Picture menu command. This makes the Open dialog box appear where you can select the image file to open as a background. The file formats that can be imported include SGI, BMP, EXR, GIF, HDR, JPEG, MAC, PCD, PNG, PSD, TGA, and TIF files.
To render the scene with a transparent background so the image can be composited with other elements, use the PNG file format.
If the Document Window is set at a resolution different than the loaded background image, a warning dialog box appears asking if you want to change the Document Window to match the image resolution. Figure 6-24 shows the Document Window with a background image loaded.
If a background image is loaded, but doesn’t appear, select Display, Show Background Picture (Ctrl+B) to make the background image visible. This menu option can also be used to hide the background image.
Loading a Background Movie
In addition to static images, Poser can also load movie files as a background. Windows systems use a File, Import, AVI Footage menu command and Macintosh systems use a File, Import, QuickTime Footage menu command. Either command makes an Open dialog box appear where you can select the appropriate file to open. Figure 6-25 shows the Document Window with a background movie.
Clearing the Background
To remove the background picture or movie, use the Display, Clear Background Picture or the Display, Clear Background Footage menu commands.
Using a Background Shader
If you open the Material Room, you can select the Background option from the Material List at the top of the Shader Window. This opens the nodes used for the background in the Shader Window, as shown in Figure 6-26. Using these nodes, you can define a shader that is rendered along with the background image or movie. To enable the designated background shader, choose the Display, Use Background Shader Node menu command.
Load a Background Picture
1. Select File, Import, Background Picture.
The Open dialog box appears.
2. Select the Oregon coast.jpg image file and click Open.
A warning dialog box appears stating that the Document Window is different than the image resolution. Click the No button to keep the Document Window the same size. The image appears in the background of the Document Window.
3. Open the Library and apply a walking pose to the character. Then use the Camera Controls to position the figure in the scene so he appears to be walking down the path.
4. Select the Display, Guides, Ground Plane menu to hide the ground plane. Then disable the view shadows using the Shadows toggle at the bottom of the Document Window.
The figure meshes with the background image, as shown in Figure 6-27.
5. Select File, Save As and save the file as Background image.pz3.
Load a Background Movie
1. Open Poser with the default figure visible.
2. Select File, Import, AVI Footage.
The Open dialog box appears.
3. Select and open the Swinging into a wall.avi movie file and click Open.
A warning dialog box appears stating that the width/height ratio is different than the Document Window. Click No to continue. The first frame of the movie appears in the background of the Document Window.
4. Open the Animation Controls and drag the Timeline to frame 10.
Frame 10 of the background video is displayed.
5. Move and rotate the figure to correspond to the background video’s character.
6. Select the Display, Guides, Ground Plane menu to hide the ground plane. Then disable the view shadows using the Shadows toggle at the bottom of the Document Window.
Aligning the figure to the background video frame by frame lets you create realistic motions, as shown in Figure 6-28.
7. Select File, Save As and save the file as Background movie.pz3.
Chapter Summary
This chapter covered two important items used to create a scene other than a posed figure and props[md]cameras and backgrounds. This chapter presented each of the available preset cameras and explained how to control them with the Camera Controls. It also included an in-depth look at the various camera parameters and showed how you could aim cameras with the Point At command and attach cameras with the parenting command. The various background options were also covered, including background colors, images, and movies.
What You Have Learned
In this chapter, you:
• Learned about the different preset cameras and how to access them.
• Used the various Camera Controls to pan and rotate the view.
• Changed the camera shortcut items to use different cameras.
• Used Flyaround mode to quickly see the scene from all angles.
• Positioned and rotated cameras to change the scene view.
• Accessed the display guides that work with cameras, including Ground Plane, Horizon Line, Vanishing Lines, and Focus Distant Guide.
• Discovered the various camera parameters and properties.
• Changed the Focal Length and F-Stop parameters to create a depth of field effect.
• Altered the Shutter Open and Shutter Close parameters to create a motion blur effect.
• Created clipping planes with the Hither and Yon parameters.
• Attached and aimed cameras to and at objects.
• Created a new background with colors, images, materials, and movies.
Key Terms from This Chapter
• Background image. An image that is set to appear behind the scene.
• Camera Dots. An interface control used to remember and recall camera position and properties.
• Clipping plane. A plane positioned parallel to the camera that defines the border beyond which scene objects aren’t visible.
• Depth of field. An optical effect that focuses the view at the focal point and gradually blurs all objects further than the focal point.
• Dolly. A camera motion that moves the view closer or farther from the scene.
• Focal length. The distance from the camera’s center where the image is in focus.
• Flyaround mode. A toggle mode that causes the camera to spin about the central axis of the current scene, animating its view from all angles.
• F-stop. A camera setting that determines the size of the aperture and that affects the intensity of the blurring for a depth of field effect.
• Motion blur. An optical effect that causes objects in motion to appeared blurred as they move through the scene.
• Orthogonal camera. A camera that is positioned at the end of an axis and displays the scene as a 2D plane where all dimensions are accurate. Top, Bottom, Front, Back, Left, and Right are examples of orthogonal cameras.
• Perspective. A optical property that displays depth by having all object edges gradually converge to a point in the distance.
• Posing camera. A camera that stays focused on the scene’s selected figure.
• Shadow camera. A camera that is positioned in the same location as a light.
• Trackball. A ball-like control within the Camera Controls that rotates the scene.
• Vanishing lines. Guide lines that lead from the edges of an object to the perspective converging point.
Kelly L. Murdock has more than 15 years experience in the computer graphics arena, especially in the area of 3D graphics. Included in the experience is a variety of tasks from high-end CAD product design and architectural pre-visualization to virtual reality and games. Kelly is best known for his international best-selling books on graphics including the 3ds max Bible, Illustrator Bible and Naked Maya. He also is the author of Poser 6 Revealed and Poser 7 Revealed as well as Edgeloop Character Modeling for 3D Professionals. Kelly currently works as a freelance designer for Logical Paradox Design, a company that he founded with his brother.
Links:
[1] http://www.courseptr.com/ProdInfo.aspx?isbn=1598639706
