Camera 3D Node

Camera 3D Node

The Camera 3D node generates a virtual camera for viewing the 3D environment. It closely emulates the settings used in real cameras to make matching live-action or 3D-rendered elements as seamless as possible. Adding any cameras to a 3D composite allows you to frame the elements in a composite how you want and animate the camera during a scene to create moving camera shots.

Camera Projection
The Camera 3D node can also be used to perform Camera Projection by projecting a 2D image through the camera into 3D space. Projecting a 2D image can be done as a simple Image Plane aligned with the camera, or as an actual projection, similar to the behavior of the Projector 3D node, with the added advantage of being aligned precisely with the camera. The Image Plane, Projection, and Materials tabs do not appear until you connect a 2D image to the magenta image input on the Camera 3D node in the Node Editor.

Stereoscopic
The Camera node has built-in stereoscopic features. They offer control over eye separation and convergence distance. The camera for the right eye can be replaced using a separate camera node connected to the green left/right stereo camera input. Additionally, the plane of focus control for depth of field rendering is also available here

If you add a camera by dragging the camera icon from the toolbar onto the 3D view, it automatically connects to the Merge 3D you are viewing. Also, the current viewer is set to look through the new camera.

Alternatively, it is possible to copy the current viewer to a camera (or spotlight or any other object) by selecting the Copy PoV To option in the viewer’s contextual menu, under the Camera submenu.

Camera 3D Node Inputs

There are three optional inputs on the Camera 3D node in the Node Editor.

  • SceneInput: The orange input is used to connect a 3D scene or object. When connected, the geometry links to the camera’s field of view. It acts similarly to an image attached to the Image Plane input. If the camera’s Projection tab has projection enabled, the image attached to the orange image input projects on to the geometry.
  • ImageInput: The optional magenta input is used to connect a 2D image. When camera projection is enabled, the image can be used as a texture. Alternatively, when the camera’s image plane controls are used, the parented planar geometry is linked to the camera’s field of view.
  • RightStereoCamera: The green input should be connected to another Camera 3D node when creating 3D stereoscopic effects. It is used to override the internal camera used for the right eye in stereoscopic renders and viewers.

Camera 3D Node Setup

The output of a camera 3D node should be connected to a Merge 3D node. You then view the Merge 3D node and select the camera from the viewer’s right-click menu or by right-clicking over the axis label in the viewer.

Displaying a camera node directly in the viewer shows only an empty scene; there is nothing for the camera to see. To view the scene through the camera, view the Merge 3D node where the camera is connected, or any node downstream of that Merge 3D. Then right-click on the viewer and select Camera > [Camera name] from the contextual menu. Right-clicking on the axis label found in the lower corner of each 3D viewer also displays the Camera submenu.

The aspect of the viewer may be different from the aspect of the camera, so the camera view may not match the actual boundaries of the image rendered by the Renderer 3D node. Guides can be enabled to represent the portion of the view that the camera sees and assist you in framing the shot. Right-click on the viewer and select an option from the Guides > Frame Aspect submenu. The default option uses the format enabled in the Composition > Frame Format preferences. To toggle the guides on or off, select Guides > Show Guides from the viewers’ contextual menu, or use the Command-G (macOS) or Ctrl-G (Windows) keyboard shortcut when the viewer is active.

Camera 3D Node Controls Tab

The Camera3D Inspector includes six tabs along the top. The first tab, called the Controls tab, contains some of the most fundamental camera settings, including the camera’s clipping plains, field of view, focal length, and stereoscopic properties. Some tabs are not displayed until a required connection is made to the Camera 3D node.

  • Projection Type
    The Projection Type menu is used to select between Perspective and Orthographic cameras. Generally, real-world cameras are perspective cameras. An orthographic camera uses parallel orthographic projection, a technique where the view plane is perpendicular to the viewing direction. This produces a parallel camera output that is undistorted by perspective. Orthographic cameras present controls only for the near and far clipping planes, and a control to set the viewing scale.
  • Near/Far Clip
    The clipping planes are used to limit what geometry in a scene is rendered based on an object’s distance from the camera’s focal point. Clipping planes ensure objects that are extremely close to the camera, as well as objects that are too far away to be useful, are excluded from the final rendering.

    The default perspective camera ignores this setting unless the Adaptive Near/Far Clip checkbox located under the Near/Far Clip control is disabled.

    The clip values use units, so a far clipping plane of 20 means that any object more than 20 units from the camera is invisible to the camera. A near clipping plane of 0.1 means that any object closer than 0.1 units is also invisible.
  • Adaptive Near/Far Clip
    When selected, the renderer automatically adjusts the camera’s near/far clipping plane to match the extents of the scene. This setting overrides the values of the Near and Far clip range controls described above. This option is not available for orthographic cameras.
  • Viewing Volume Size
    When the Projection Type is set to Orthographic, the viewing volume size adjustment appears. It determines the size of the box that makes up the camera’s field of view.

    The Z-distance of an orthographic camera from the objects it sees does not affect the scale of those objects, only the viewing size does.
  • Angle of View Type
    Use the Angle of View Type buttons to choose how the camera’s angle of view is measured. Some applications use vertical measurements, some use horizontal, and others use diagonal measurements. Changing the Angle of View type causes the Angle of View control below to recalculate.
  • Angle of View
    Angle of View defines the area of the scene that can be viewed through the camera. Generally, the human eye can see more of a scene than a camera, and various lenses record different degrees of the total image. A large value produces a wider angle of view, and a smaller value produces a narrower, or more tightly focused, angle of view.

    Just as in a real-world camera, the angle of view and focal length controls are directly related. Smaller focal lengths produce a wider angle of view, so changing one control automatically changes the other to match.
  • Focal Length
    In the real world, a lens’ Focal Length is the distance from the center of the lens to the film plane. The shorter the focal length, the closer the focal plane is to the back of the lens. The focal length is measured in millimeters. The angle of view and focal length controls are directly related. Smaller focal lengths produce a wider angle of view, so changing one control automatically changes the other to match.

    The relationship between focal length and angle of view is angle = 2 * arctan[aperture / 2 / focal_length].

    Use the vertical aperture size to get the vertical angle of view and the horizontal aperture size to get the horizontal angle of view.
  • Plane of Focus (For Depth of Field)
    Like a focal point on a real-world camera, this setting defines the distance from the camera to an object. It is used by the OpenGL renderer in the Renderer 3D node to calculate depth of field.
  • Stereo
    The Stereo section includes options for setting up 3D stereoscopic cameras. 3D stereoscopic composites work by capturing two slightly different views, displayed separately to the left and right eyes. The mode menu determines if the current camera is a stereoscopic setup or a mono camera. When set to the default mono setting, the camera views the scene as a traditional 2D film camera. Three other options in the mode menu determine the method used for 3D stereoscopic cameras.
    • Toe In
      In a toe-in setup, both cameras are rotating in on a single focal point. Though the result is stereoscopic, the vertical parallax introduced by this method can cause discomfort by the audience. Toe-in stereoscopic works for convergence around the center of the images but exhibits keystoning, or image separation, to the left and right edges. This setup is can be used when the focus point and the convergence point need to be the same. It is also used in cases where it is the only way to match a liveaction camera rig.
    • Off Axis
      Regarded as the correct way to create stereo pairs, this is the default method in Fusion. Off Axis introduces no vertical parallax, thus creating stereo images with less eye strain. Sometimes called a skewed-frustum setup, this is akin to a lens shift in the real world. Instead of rotating the two cameras inward as in a toe-in setup, Off Axis shifts the lenses inward.
    • Parallel
      The cameras are shifted parallel to each other. Since this is a purely parallel shift, there is no Convergence Distance control that limits your control over placing objects in front of or behind the screen. However, Parallel introduces no vertical parallax, thus creating less strain on the eyes.
    • Rig Attached To
      This drop-down menu allows you to control which camera is used to transform the stereoscopic setup. Based on this menu, transform controls appear in the viewer either on the right camera, left camera, or between the two cameras. The ability to switch the transform controls through rigging can assist in matching the animation path to a camera crane or other live-action camera motion. The Center option places the transform controls between the two cameras and moves each evenly as the separation and convergence are adjusted. Left puts the transform controls on the left camera, and the right camera moves as the separation and convergence are adjusted. Right puts the transform controls on the right camera, and the left camera moves as adjustments are made to separation and convergence.
    • Eye Separation
      Eye Separation defines the distance between both stereo cameras. Setting Eye Separation to a value larger than 0 shows controls for each camera in the viewer when this node is selected. Note that there is no Convergence Distance control in Parallel mode
    • Convergence Distance
      This control sets the stereoscopic convergence distance, defined as a point located along the Z-axis of the camera that determines where both left- and right-eye cameras converge. The Convergence Distance controls are only available when setting the Mode menu to Toe-In or Off Axis.
  • Film Back
    • Film Gate
      The size of the film gate represents the dimensions of the aperture. Instead of setting the aperture’s width and height, you can choose it using the list of preset camera types in the Film Gate menu. Selecting one of the options automatically sets the aperture width and aperture height to match.
    • Aperture Width/Height
      The Aperture Width and Height sliders control the dimensions of the camera’s aperture or the portion of the camera that lets light in on a real-world camera. In video and film cameras, the aperture is the mask opening that defines the area of each frame exposed. The Aperture control uses inches as its unit of measurement.
    • Resolution Gate Fit
      Determines how the film gate is fitted within the resolution gate. This only has an effect when the aspect of the film gate is not the same aspect as the output image.
      • Inside: The image source defined by the film gate is scaled uniformly until one of its dimensions (X or Y) fits the inside dimensions of the resolution gate mask. Depending on the relative dimensions of image source and mask background, either the image source’s width or height may be cropped to fit the dimension of the mask.
      • Width: The image source defined by the film gate is scaled uniformly until its width (X) fits the width of the resolution gate mask. Depending on the relative dimensions of image source and mask, the image source’s Y-dimension might not fit the mask’s Y-dimension, resulting in either cropping of the image source in Y or the image source not covering the mask’s height entirely.
      • Height: The image source defined by the film gate is scaled uniformly until its height (Y) fits the height of the resolution gate mask. Depending on the relative dimensions of image source and mask, the image source’s X-dimension might not fit the mask’s X-dimension, resulting in either cropping of the image source in X or the image source not covering the mask’s width entirely.
      • Outside: The image source defined by the film gate is scaled uniformly until one of its dimensions (X or Y) fits the outside dimensions of the resolution gate mask. Depending on the relative dimensions of image source and mask, either the image source’s width or height may be cropped or not fit the dimension of the mask.
      • Stretch: The image source defined by the film gate is stretched in X and Y to accommodate the full dimensions of the generated resolution gate mask. This might lead to visible distortions of the image source.
  • Control Visibility
    This section allows you to selectively activate the onscreen controls that are displayed along with the camera.
    • Show View Controls: Displays or hides all camera onscreen controls in the viewers.
    • Frustum: Displays the actual viewing cone of the camera.
    • View Vector: Displays a white line inside the viewing cone, which can be used to determine the shift when in Parallel mode.
    • Near Clip: The Near clipping plane. This plane can be subdivided for better visibility.
    • Far Clip: The Far clipping plane. This plane can be subdivided for better visibility.
    • Focal Plane: The plane based on the Plane of Focus slider explained in the Controls tab above. This plane can be subdivided for better visibility.
    • Convergence Distance: The point of convergence when using Stereo mode. This plane can be subdivided for better visibility.
  • Import Camera
    The Import Camera button displays a dialog to import a camera from another application.

    It supports the following file types:
*LightWave Scene.lws
*Max Scene.ase
*Maya Ascii Scene.ma
*dotXSI.xsi

Camera 3D Node Image Tab

When a 2D image is connected to the magenta image input on the Camera3D node, an Image tab is created at the top of the inspector. The connected image is always oriented so it fills the camera’s field of view.

Except for the controls listed below, the options in this tab are identical to those commonly found in other 3D nodes. For more detail on visibility, lighting, matte, blend mode, normals/tangents, and Object ID, see The Common Controls.

  • Enable Image Plane
    Use this checkbox to enable or disable the usage of the Image Plane.
  • Fill Method
    This menu configures how to scale the image plane if the camera has a different aspect ratio.
    • Inside: The image plane is scaled uniformly until one of its dimensions (X or Y) fits the inside dimensions of the resolution gate mask. Depending on the relative dimensions of image source and mask background, either the image source’s width or height may be cropped to fit the dimensions of the mask.
    • Width: The image plane is scaled uniformly until its width (X) fits the width of the mask. Depending on the relative dimensions of image source and the resolution gate mask, the image source’s Y-dimension might not fit the mask’s Y-dimension, resulting in either cropping of the image source in Y or the image source not covering the mask’s height entirely.
    • Height: The image plane is scaled uniformly until its height (Y) fits the height of the mask. Depending on the relative dimensions of image source and the resolution gate mask, the image source’s X-dimension might not fit the mask’s X-dimension, resulting in either cropping of the image source in X or the image source not covering the mask’s width entirely.
    • Outside: The image plane is scaled uniformly until one of its dimensions (X or Y) fits the outside dimensions of the resolution gate mask. Depending on the relative dimensions of image source and mask, either the image source’s width or height may be cropped or not fit the respective dimension of the mask.
  • Depth: The Depth slider controls the image plane’s distance from the camera.

Camera 3D Node Materials Tab

The options presented in the Materials tab are identical to those commonly found in other 3D nodes. For more detail on Diffuse, Specular, Transmittance, and Martial ID controls, see the Common Controls HERE

Camera 3D Node Projection Tab

When a 2D image is connected to the camera node, a fourth projection tab is displayed at the top of the Inspector. Using this Projection tab, it is possible to project the image into the scene. A projection is different from an image plane in that the projection falls onto the geometry in the scene exactly as if there were a physical projector present in the scene. The image is projected as light, which means the Renderer 3D node must be set to enable lighting for the projection to be visible.

  • Enable Camera Projection
    Select this checkbox to enable projection of the 2D image connected to the magenta input on the Camera node.
  • Projection Fit Method
    This menu can be used to select the method used to match the aspect of the projected image to the camera’s field of view.
  • Projection Mode
    • Light: Defines the projection as a spotlight.
    • Ambient Light: Defines the projection as an ambient light.
    • Texture: Allows a projection that can be relighted using other lights. Using this setting requires a Catcher node connected to the applicable inputs of the specific material.

Camera 3D Node Transform and Settings Tabs

The options presented in the Transform and Settings tabs are commonly found in other 3D nodes, see the Common Controls HERE

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