V-Ray Physical Camera
The V-Ray Physical Camera is a lens shader that can be assigned to every standard Softimage camera. It can also be created by going to Get>Primitive>Camera> V-Ray Physical Camera
The VRayPhysicalCamera allows you to use real-world parameters to set up the virtual CG camera (e.g. f-number, lens focal length etc). It also makes it easier to use light sources with real-world illumination (e.g. VRayLight with physical units, or VRaySun and VRaySky).
Type - determines the type of the camera. This mostly has an effect on the motion blur effect produced by the camera:
Still camera - simulates a still photo camera with a regular shutter.
Movie camera - simulates a motion-picture camera with a circular shutter.
Video camera - simulates a shutter-less video camera with a CCD matrix.
Film gate(mm) - specifies the horizontal size of the film gate in millimeters. Note that this setting takes into account the system units configuration to produce the correct result.
Get FOV from camera - when enabled the field of view of the physical camera will be controlled through the field of view angle parameter of the standard Softimage camera to which the lens shader is assigned.
FOV - a value for the Field of View of the camera
Zoom factor - specifies a zoom factor. Values greater than 1.0 zoom into the image; values smaller than 1.0 zoom out. This is similar to a blow-up rendering of the image.
F-number - determines the width of the camera aperture.
Distortion amount - specifies the distortion coefficient for the camera lens. A value of 0.0 means no distortion; positive values produce "barrel" distortion, while negative values produce "pillow" distortion.
Distortion type - determines what formula is used to calculate the distortion for the camera
Quadratic - this is the default distortion type. It uses a simplified formula that is easier to calculate than the Cubic method.
Cubic - this is the distortion type used in some camera tracking programs like SynthEyes, Boujou etc. If you plan on using one of these programs, you should use the Cubic distortion type.
Lens file - an external .lens file is used to determine the distortion for the camera
Texture - a displacement map from Nuke can be used to determine the camera distortion
Distortion map - load the texture that is going to be used to determine the camera distortion. This is only available when the Distortion type is set to Texture.
Lens file - load a file that is going to be used to calculate the camera distortion. This is only available when the Distortion type is set to Lens file.
Vertical shift - allows the simulation of shift lenses for 2-point perspective.
Specify focus - this allows you to specify a focus distance different from the camera target distance.
Focus distance - sets the focus distance of the camera.
Exposure - when this option is on, the f-number, Shutter speed and Film Speed (ISO) settings will affect the image brightness.
Enable Vignetting - when this option is on, the optical vignetting effect of real-world cameras is simulated.
Vignetting - specifies the amount of the vignetting effect, where 0.0 is no vignetting and 1.0 is normal vignetting.
White balance - allows additional modification of the image output. Objects in the scene that have the specified color will appear white in the image. Note that only the color hue is taken into consideration; the brightness of the color is ignored.
Shutter speed - the shutter speed, in inverse seconds, for the still photographic camera. For example, shutter speed of 1/30 s corresponds to a value of 30 for this parameter.
Shutter angle - shutter angle (in degrees) for the cinematic camera.
Shutter offset - shutter offset (in degrees) for the cinematic camera.
Latency - CCD matrix latency, in seconds, for the video camera.
Film speed (ISO) - determines the film power (i.e. sensitivity). Smaller values make the image darker, while larger values make it brighter.
Blades enable - defines the shape of the camera aperture. When this option is off, perfectly circular aperture is simulated. When on, a polygonal aperture is simulated. This option has effect when depth-of field is enabled.
Blades num - specifies the number of blades of the polygonal aperture.
Rotation (deg) - defines the rotation of the blades.
Center bias - defines a bias shape for the bokeh effects. Positive values make the outer edge of the bokeh effects brighter; negative values make the center of the effect brighter.
Anisotropy - allows stretching of the bokeh effect horizontally or vertically to simulate anamorphic lenses.
Depth-of-field - turns on depth of field sampling.
Subdivisions - determines the number of samples (rays) for calculating depth of field and/or motion blur.
Enable motion blur sampling - turns on motion blur sampling.
Note: Focal length and distance to camera's interest are respectively available in Projection plane tab and Primitive tab of Softimage camera property page.
- There are three types of FoV (field of view): horizontal, vertical and diagonal. Horizontal FoV depends on the film gate size, focal length, focus distance and zoom factor. In addition to those four parameters, the vertical and diagonal FoV depend on the image aspect ratio.