User Manual

Table Of Contents
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.
NOTE: A smaller range between the near and far clipping planes allows greater
accuracy in all depth calculations. If a scene begins to render strange artifacts on
distant objects, try increasing the distance for the Near Clip plane.
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].
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