The camera options control the way the scene geometry is projected onto the image, therefore changing how the render looks. These attributes override the following:
UI Path: ||Render Settings window|| > Overrides tab > Camera rollout  |
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This page provides information on the Camera overrides rollout in the Render Settings.
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The cameras in V-Ray generally define the rays that are cast into the scene, which essentially is how the scene is then projected onto the viewing screen. V-Ray supports several camera types described below with sample renders in the next section.
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The parameters in this rollout are ignored if you are rendering using Physical camera Attributes. Exception applies for the Overscan, Geometry samples, Auto Exposure and Auto White Balance. |
Auto Exposure – Automatically determines an appropriate exposure value for the render. This option requires Light Cache in Single frame mode.
Auto White Balance – Automatically determines a suitable white balance value for the image. This option requires Light Cache in Single frame mode.
Auto Corrections Mode – Specifies which camera and/or views to use the automatic exposure and white balance setting. This option is available only if Auto Exposure/Auto white balance are enabled.
All cameras – Applies Auto Exposure and Auto White Balance to all cameras, regardless of their local exposure settings.
Cameras without exposure only – Applies Auto Exposure and Auto White Balance only to cameras with no local exposure settings.
Transfer to selected camera button – This option is available only if Auto Exposure/Auto white balance are enabled. It lets you transfer the calculations to a selected camera as an ISO correction, keeping the options affecting Depth of Field and Motion Blur unchanged (e.g. shutter speed, f-number).
Camera Type – Types of cameras available in V-Ray. You may set your scene camera to be overridden by selecting one of the following: ( For more information, see the Camera Types example or the Camera Types Explained example below)
Standard – Allows for the current scene camera to be used (usually a pinhole camera).
Spherical – A camera with a spherically shaped lens.
Cylindrical (point) – This camera casts all rays from the center of a cylinder. In the vertical direction, the camera acts as a pinhole camera, and in the horizontal direction, the camera acts as a spherical camera.
Cylindrical (ortho) – This camera casts all rays from the center of a cylinder. In the vertical direction, the camera acts as an orthographic view, and in the horizontal direction, the camera acts as a spherical camera.
Box – Six standard cameras placed on the sides of a box. This type of camera is excellent for generation of environment maps for cube mapping and generates a vertical cross format image.
Fish eye – This special type of camera captures the scene as if it is a pinhole camera pointed at a 100% reflective sphere that reflects the scene back into the camera's shutter, as with using a light probe in HDRI photography. You can use the Dist and FOV settings to control which part of the sphere is captured by the camera. Note that the virtual reflective sphere has always a radius of 1.0.
Warped spherical (old-style) – A spherical camera with slightly different mapping formula than the Spherical camera.
Orthogonal – An orthographic camera enabling flat, non-perspective views.
Pinhole – Overrides the scene camera to force it to be a pinhole camera.
Spherical panorama – Spherical camera with independent horizontal and vertical FOV selection that is useful for generating lat-long images for spherical VR use.
Cube6x1 – A variant of the Box camera with the cube sides arranged in a single row. Unlike the Box camera's output, Cube6x1 does not produce an empty space in the output image and is quite useful in generating cubic VR output.
When rendering with V-Ray GPU engine, the supported Camera Types are Standard, Orthogonal, Spherical panorama and Cube 6x1. |
Overscan mode – The ability to render an extra region beyond the specified image resolution.
None – Does not expand the image resolution area.
Equal margin on all sides – Renders an equal overscan area around the image as specified by the Overscan values.
Horizontal and vertical margins – Renders an overscan area along the top/bottom and sides of the image, as defined by the Oversan values which are expanded to two values by this setting. The first value defines the left/right edges overscan area and the second value defines the top/bottom areas of ovescan in the render.
Left, right, top and bottom margins – Renders four user-defined overscan areas around the image. Overscan values are expanded to four independent values, ordered left, right, top, and bottom.
Overscan values – The numerical amount used for the Overscan mode setting.
Overscan units – Specifies the kind of units to be used by the Overscan values setting.
Override FOV – Overrides Maya's camera FOV (field-of-view) angle. Some V-Ray camera types can take FOV ranges from 0 to 360 degrees, whereas the cameras in Maya are limited to 180 degrees.
FOV – The FOV (field-of-view) value to override the Maya camera's own FOV setting. This parameter appears only when Override FOV checkbox is enabled.
Depth of Field – Toggles on or off additional parameters to control depth of field. See Depth of Field Parameters below.
Motion blur – Toggles on or off additional parameters to control motion blur. See Motion Blur Parameters below.
Height – Specifies the height of a Cylindrical (ortho) camera. This setting is available only when the Camera type is set to Cylindrical (ortho).
Auto-fit – Controls the auto-fit option of the Fish-eye camera. When enabled, V-Ray calculates the Dist value automatically so that the rendered image fits horizontally with the image's dimensions.
Dist – Applies only to the Fish eye camera. The Fish eye camera is simulated as a Standard camera pointed to an absolutely reflective sphere (with a radius of 1.0) that reflects the scene into the camera's shutter. The Dist value controls how far the camera is from the sphere's center (which is how much of the sphere will be captured by the camera). This setting has no effect when the Auto-fit option is enabled.
Curve – Controls the degree of warping for a Fish eye camera. A value of 1.0 corresponds to a real world fish-eye camera. Lower values increase warping, while higher values reduce warping. Technically, this value controls the angle at which rays are reflected by the virtual sphere of the camera.
Vertical FOV – Specifies the field-of-view angle in a vertical direction.
Ignore image planes – Enables/disables the rendering of all camera image planes in the scene. This option does not affect free image planes.
The images below show the difference between the different camera types used in rendering:
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This example shows how the rays for different camera types are generated. The red arcs in the diagrams correspond to the FOV angles.
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These parameters, which appear when the Depth of Field option is enabled, control the depth of field effect when rendering with a standard Maya camera. The parameters are ignored if you render with Physical camera Attributes.
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These parameters, which appear when the Motion Blur option is enabled, set values for calculations of the Motion Blur effect. For more information, see the Motion Blur example below.
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This example demonstrates how motion blur works.
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The following scene consists of three-frame animation of a moving cube. The cube's position on each frame:
Frame 0: Left side
Frame 1: Near box
Frame 2: Right side
The following images show frame 1 rendered with different duration values:
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This example demonstrates the effect of the interval center parameter. The scene is a moving sphere. Here are three sequential frames without motion blur:
Here is the middle frame, rendered with motion blur and three different values for the interval center; the motion blur duration is one frame.
Interval center = 0.0; the middle of the motion blur interval matches the sphere position at the second frame
Interval center = 0.5; the middle of the interval is halfway between the second and the third frame
Interval center = 1.0; the middle of the interval matches the sphere position at the third frame
Interval center = 4; the middle of the interval matches the sphere position at the sixth frame
Interval center = 8; the middle of the interval matches the sphere position at the twelfth frame
The following images demonstrate the Geometry samples parameter using the scene from the Duration example. In all the following renderings, the Duration (frames) parameter is set to 2. All other parameters are the same as for the previous images. The higher the value for Geometry samples, the more accurate the estimated object motion. However, excessive increase of this value will result in long rendering times.
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The number of geometry samples can be controlled on a per-object basis on the Object Properties dialog. This is useful if you need a lot of samples for some objects in the scene (for example, the wheels of a moving car) while other objects can do with fewer samples (such as the car body). Using more samples only where needed saves memory and speeds rendering.
Spherical
