This page provides information on the Physical camera attributes.


Overview


The V-Ray Physical Camera uses real-world camera settings such as f-stop, focal length, and shutter speed to set up the virtual CG camera. It also makes it easier to use light sources with real-world illumination, such as V-Ray Lights with physical units or V-Ray Sun and Sky.


UI Path: V-Ray menu > Cameras > Physical Camera

UI Path: V-Ray menu > Cameras > Physical Camera


UI Path: V-Ray Toolbar > Physical Camera


General


Camera Type – Specifies the camera type. This mostly has an effect on the motion blur effect produced by the camera.

Still cam – Simulates a still photo camera with a regular shutter.
Movie cam – Simulates a motion-picture camera with a circular shutter.
Video cam – Simulates a shutterless video camera with a CCD matrix.



Sensor and Lens


Specify Field of View – When enabled, sets the field of view directly without having to set up the Film Gate (mm) and Focal Length (mm).

Field of View – Specifies the field of view in degrees.

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. Vertical film gate size is calculated by accounting image aspect ratio (vertical film size = horizontal film size / aspect ratio). 

Focal Length (mm) – Specifies the equivalent focal length of the camera lens. This setting takes into account the system units configuration to produce the correct result.

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. See the Zoom Factor example for more information.





Example: Exposure, Field of View and Focus Distance


The Focus Distance of the Cinema 4D physical camera affects the exposure of the image and the field of view for the camera, especially if the Focus Distance is close to the camera. This is an effect that can be observed with real-world cameras as demonstrated in the images below.

The set up is a white board with a small black rectangle and a camera in front of it. Notice how changing the Focus Distance produces images with different brightness, even though the illumination and all other camera parameters are the same in both cases. Also notice the change in the Field of View.


The camera is focused on the white board; the grey color is approximately RGB 104, 104, 104.

The camera is focused at infinity; the grey color is approximately RGB 135, 135, 135.

Side view of the camera focused on the white board.

Side view of the camera focused at infinity.


Aperture


Film Speed (ISO) – Determines the film power (i.e. sensitivity). Smaller values make the image darker, while larger values make it brighter. See the Film Speed (ISO) example for more information. This option is not available for V-Ray GPU.

F-Number – Determines the width of the camera aperture and, indirectly, exposure. If the Exposure option is set to Physical Exposure or Exposure Value, changing the F-number affects the image brightness. See the F-Number example below for more information.

Shutter Speed (s^-1) – Specifies the shutter speed, in inverse seconds, for the Still Camera Type. For example, shutter speed of 1/30 s corresponds to a value of 30 for this parameter. See the Shutter Speed example for more information.

Shutter Angle Specifies the shutter angle (in degrees) for the Movie Camera Type.

Shutter Offset – Specifies the shutter offset (in degrees) for the Movie Camera Type.

Latency (s) – Specifies the CCD matrix latency (in seconds) when the Camera Type is set to Video. This option is not available for V-Ray GPU.





Aperture F-number vs Shutter Speed vs ISO
Cheat Sheet


The main options that control the brightness of a V-Ray Physical camera are Aperture F-number, Shutter Speed and ISO. They affect each other and you need to balance them according to your scene. Keep in mind that these settings do not correspond to those of a real-life camera. They apply only to the V-Ray Physical camera.

  • F-number determines the size of the opening in the camera lens. What the number refers to is the ratio between the aperture's focal length and the actual diameter of the aperture. A smaller F-number means a larger aperture. The larger the Aperture, the brighter the scene becomes but that also introduces more Depth of field.

  • Shutter Speed determines how long the lens stays open when taking the photo. The numbers refer to fractions of a second. The slower the Shutter Speed, the brighter the scene becomes but that also introduces Motion Blur.

  • ISO determines the camera's sensitivity to light in the scene. Lowering the ISO means that more light is needed to achieve good lighting. Increasing the ISO means that less light is needed to achieve good lighting. A day scene, lit with a V-Ray Sun, for instance, looks best when captured with around 100 ISO.





Color and Exposure


Exposure – Specifies how the F-number, Shutter Speed (s^-1), and Film Speed (ISO) settings affect the image brightness. 

No Exposure – Shutter Speed (s^-1)F-Number and Film Speed (ISO) settings do not affect the image brightness;
Physical Exposure – Image brightness is controlled by the Shutter speed (s^-1)F-Number and Film Speed (ISO);
Exposure Value (EV) – Uses the Exposure Value to control image brightness. Grays out the ISO parameter and uses the Shutter speed (s^-1) and F-number values only for Motion Blur and Depth of field, respectively.

Exposure Value – Controls the exposure value when the Exposure Value (EV) option is selected.

Vignetting – When enabled, simulates the optical vignetting effect of real-world cameras. The strength of the vignetting effect can be specified, where 0.0 is no vignetting and 1.0 is normal vignetting. See the Vignetting example below for more information.

White Balance – Allows additional modification of the image output. Objects in the scene that have the specified color appear white in the image. Note that only the color hue is taken into consideration; the brightness of the color is ignored. See the White Balance example for more information.



Tilt and Shift


Vertical Tilt – Vertical tilt that allows the simulation of tilt lenses for 2-point perspective. See the Vertical Tilt example for more information.

Horizontal Tilt – Horizontal tilt that allows the simulation of tilt lenses for 2-point perspective. Changing these parameters is similar to applying a camera correction modifier. See the Horizontal Tilt example for more information.

Vertical Shift – Vertically offsets the camera field of view as a fraction of the current view. For example, a value of 0.5 offsets the camera by half of the current image height in an upwards direction. See the Vertical Shift example for more information.

Horizontal Shift – Horizontally offsets the camera field of view as a fraction of the current view. For example, a value of 0.5 offsets the camera by half of the current image width to the left. See the Horizontal Shift example for more information.



Depth of Field


Enabled – Enables the depth of field effect. Note that depth of field depends on the F-Number parameter. See the Depth of Field example for more information.



Bokeh Effects


Aperture Shape – Defines the shape of the camera aperture. When disabled, a perfectly circular aperture is simulated. When enabled, a polygonal aperture is simulated, with the specified number of blades.

Blades Number – Specifies the number of blades of the aperture.

Rotation – Rotates the blades (value in degrees).

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. If you want the ratio of height to width of the bokeh to be k:1,  then the value for Anisotropy should be √(1/k)-1For example, for anamorphic bokeh, which is 2.39:1, the Anisotropy value should be -0.353. 

Optical Vignetting – Controls the strength of the optical vignetting, also known as and cat's eye vignetting. This effect is due to the fact that the shape of the bokeh highlights resembles the shape of the aperture. As the distance to the optical axis increases, the bokeh highlights are progressively narrowed and begin to resemble the shape of a cat's eye. The larger the distance from the image center, the narrower the cat's eye becomes. Optical vignetting tends to be stronger in wide angle lenses and large aperture lenses, but the effect can be noticed with most photographic lenses.

Optical vignetting is currently very slow to calculate; it may introduce noise in the image that is difficult to clean.

Bitmap Aperture

Enabled – Enables the use of an image (specified in the field below) to control the aperture shape, as well as any dirt or scratches that may affect the bokeh. White signifies transparent areas and black signifies opaque areas.

File – Specifies the image file.

Bitmap Resolution – Specifies the sampling texture resolution when calculating the bokeh effects.

Affect Exposure – When enabled, the bokeh effects affect the overall exposure of the image.



Motion Blur


Enabled – Enables motion blur. Note that motion blur depends on how fast the objects are moving, as well as the camera's Shutter Speed. See the Motion Blur example for more information.

Mode – Specifies whether the rolling shutter effect is enabled and the direction of the shutter.

Disabled
Top to bottom
Bottom to top
Left to right
Right to left

Duration (s^-1) – The time for the shutter to pass through the image in 1/seconds.



Distortion


Type – Specifies how the distortion is determined.

Quadratic – The default distortion type. It uses a simplified formula that is easier to calculate than the Cubic method. 
Cubic
 – Used in some camera tracking programs like SynthEyes, Boujou, etc. If you plan on using one of these programs, this distortion type should be used. 
Lens File
 – Uses a .lens file generated with the V-Ray Lens Analysis tool and specified in the Lens File field. 
Texture
 – Uses a texture file generated in a third party application (i.e. Nuke) and specified in the Distortion Texture field.

Amount – Specifies the distortion coefficient for the camera lens when the Distortion Type is set to either Quadratic or Cubic. A value of 0.0 means no distortion; positive values produce "barrel" distortion, while negative values produce "pillow" distortion. See the Distortion example below for more information.

Distortion Texture –  When the Distortion Type is set to Texture, this slot specifies the color that determines the distortion, or the map that contains the distortion data. This option is not available for V-Ray GPU.

Lens File – When the Distortion Type is set to Lens File, this slot specifies the lens file, containing the distortion data. 


 


Auto Exposure


Auto Exposure and Auto White Balance are only calculated during Production Rendering.

Auto Exposure – When enabled, automatically calculates an appropriate exposure value for the render. This option requires Light Cache in Single frame mode. This can be set in the GI tab of the Render Settings. 

Disabled – Auto Exposure is not applied.
Center-weighted Average – Calculates the exposure by evaluating the light in the center of the frame and its surroundings, ignoring the corners.
Histogram – Calculates a histogram of the image, which allows very bright or very dark areas of the scene to be excluded from the exposure calculations, creating a more balanced result.

Auto White Balance – Automatically determines a suitable white balance value for the image. This option requires Light Cache in Single frame mode. This can be set in the GI tab of the Render Settings.

Transfer – This option, for both the Auto Exposure and the Auto White Balance, becomes available after the calculations are complete. When activated, this option transfers the automatically calculated values for either Film Speed (ISO) or White Balance, respectively, onto the camera's options.


Overrides


These options override the values entered in the Camera Overrides tab of the Render Settings for the current camera.

Override Global Camera Settings – Enables the per-camera override options. The rollout is grayed out if this option is disabled.

Camera Type – Types of cameras available in V-Ray. Depending on the camera type, different options become available in the rollout. You may set the current camera to be overridden by selecting one of the following:

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 Distance 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.

Height – Specifies the height of a Cylindrical (ortho) camera. 

Auto-fit Controls the auto-fit option of the Fish Eye camera. When enabled, V-Ray calculates the Distance value automatically so that the rendered image fits horizontally with the image's dimensions.

Distance – Determines the focal distance of the Fish Eye camera. We recommend using the Auto-fit option for a fast, realistic look.

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.

Override FOVOverrides the Cinema 4D'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 Cinema 4D are limited to 180 degrees.

FOV – Determines the new field of view for the current camera.


Stereo


Enabled Specifies the format in which the Stereoscopic renders are output. See the example below for visual illustration of the options.

Disabled – Disables stereoscopic rendering.
Enabled, Side-by-Side
– Arranges the rendered images for each eye side by side. 
Enabled, Top-Bottom
 – Arranges the rendered images for each eye one on top of another.

Eye DistanceSpecifies the eye distance for which the stereoscopic image is rendered. 

Interocular MethodSpecifies how the two virtual cameras are placed in relation to the real camera in the scene. 

Center – Both virtual cameras are shifted in opposite directions at a distance equal to half of the eye distance.
Keep Left View – The virtual cameras are shifted to the left so that the right camera takes the position of the original camera. The left camera is shifted to the left at a distance equal to the eye distance. 
Keep Right View  – The virtual cameras are shifted to the right so that the left camera takes the position of the original camera. The right camera is shifted to the right at a distance equal to the eye distance. 

Specify FocusWhen enabled, allows a point of focus to be defined.

Focus DistanceDefines the point of focus.

Focus Method Specifies the focus method for the two views. Possible values are: 

Parallel – Both cameras have their focus points directly in front of them. 
Rotate  – Achieves the stereoscopic effect by rotating the left and right views, so that their focus points coincide at the distance from the eyes. That is where the lines of sight for each eye converge (known as fusion distance). 
Shift – The orientation of both views remains the same, but each eye's view is sheared along the Z axis so that the two frustums converge at the fusion distance.

View – Specifies which of the stereoscopic views are rendered. 

Both Views – Both views are rendered side by side. 
Left View – Only the left view is rendered. 
Right View – Only the right view is rendered.

The following options are used when rendering a panoramic view with stereoscopy (for example a Spherical camera with FOV=360 degrees). These options help avoid artifacts when the camera looks upward and downward. This is achieved by gradually decreasing the eye distance and thus the stereoscopic effect. The eye distance value is kept the same until the viewing angle reaches the angles specified, after which the eye distance is gradually decreased until it reaches a value of 0 when looking directly downwards or upwards.

Top Merge Angle – Specifies the viewing angle from the horizontal plane at which the pole merging effect starts. The horizontal plane is considered to be at 0.

Bottom Merge Angle – Specifies the viewing angle from the horizontal plane at which the pole merging effect ends. The horizontal plane is considered to be at 0.


C4d2024_62001_PhysicalCamera_Stereo

Examples



Example: Zoom Factor


This parameter determines the zooming (in and out) of the final image. It doesn't move the camera forward nor backwards.

 The following constant settings are used for some parameters:  Exposure is set to Physical Exposure, Shutter Speed is 250, F-Number is 4.0, Film Speed (ISO) is 100, Vignetting is 1.0, and White Balance is set to white.


Zoom Factor = 0.5

Zoom Factor = 1

Zoom Factor = 2

Move the slider to see the other images.





Example: Film Speed (ISO)


The Film Speed (ISO) parameter determines the sensitivity of the film and consequently the brightness of the image. If the ISO value is high (film is more sensitive to light), the image is brighter. Lower ISO values mean that the film is less sensitive and produces a darker image.

The images in this example show the effect of changing the Film Speed (ISO). The following constant settings are used for some parameters: Exposure is set to Physical Exposure, Shutter Speed is 125, F-Number is 4.0, Vignetting is 1.0, and White Balance is white.


Film Speed (ISO) = 50

Film Speed (ISO) = 100

Film Speed (ISO) = 200

Move the slider to see the other images.





Example: F-Number


The F-Number parameter controls the aperture size of the virtual camera. Lowering the F-Number value increases the aperture size and so makes the image brighter since more light enters the camera. In reverse, increasing the F-Number makes the image darker, as the aperture is closed. This parameter also determines the amount of the Depth of Field (DOF) effect.

The images in this example show the effect of changing the F-Number. The following constant settings are used for some parameters: Exposure is set to Physical Exposure, Shutter Speed is 125, ISO is 100, Vignetting is 1.0, and White Balance is white.


F-Number = 2.8

F-Number = 4

F-Number = 5.6

Move the slider to see the other images.





Example: Shutter Speed


The Shutter Speed (s^-1) parameter determines the exposure time for the virtual camera. The longer this time is (small shutter speed values), the brighter the image is. In reverse - if the exposure time is shorter (high shutter speed value), the image gets darker. This parameter also affects the motion blur effect.

The images in this example show the effect of changing the Shutter Speed (s^-1). The following constant settings are used for some parameters: Exposure is set to Physical Exposure, F-Number is 4.0, ISO is 100, Vignetting is 1.0, and White Balance is white.


Shutter Speed (s^-1) = 60

Shutter Speed (s^-1) = 125

Shutter Speed (s^-1) = 250

Move the slider to see the other images.





Example: Vignetting


This parameter control the optical vignetting effect of real-world cameras. Exposure is set to Physical Exposure, F-Number is 8, Shutter Speed is 60, ISO is 100, Depth of Field is enabled and White Balance is white.


0.0
3.5

Move the slider to see the other images.





Example: White Balance


Using the White Balance color allows additional modification of the image output. Objects in the scene that have the specified color appear white in the image, e.g. for daylight scenes this should be peach color to compensate for the color of the sun light etc.

The images in this example show the effect of changing the White Balance. The following constant settings are used for some parameters: Exposure is set to Physical Exposure, F-Number is 8, Shutter Speed is 60, ISO is 100, Depth of Field is enabled.


White Balance = 255, 255, 255 /white/

White Balance = 179, 208, 255 /warm/

White Balance = 255, 192, 127 /cold/

Move the slider to see the other images.





Example: Vertical Tilt


Using this parameter, you can achieve a 2-point perspective. The following constant settings are used for some parameters: Exposure is set to Physical Exposure, F-Number is 4, Shutter Speed is 125, ISO is 100, White Balance is white.


Vertical Tilt = 0.3

Vertical Tilt = 0

Vertical Tilt = -0.3

Move the slider to see the other images.





Example: Horizontal Tilt


Using this parameter, you can achieve a 2-point perspective. The following constant settings are used for some parameters: Exposure is set to Physical Exposure, F-Number is 4, Shutter Speed is 125, ISO is 100, White Balance is white.


Horizontal Tilt = 0.3

Horizontal Tilt = 0

Horizontal Tilt = -0.3

Move the slider to see the other images.





Example: Vertical Shift


Using this parameter, you can offset the camera Field of View. For the images in this example, the following constant settings are used for some parameters: Exposure is set to Physical Exposure, F-Number is 4, Shutter Speed is 125, ISO is 100, White Balance is white.


Vertical Shift = 0.15

Vertical Shift = 0

Vertical Shift = -0.15

Move the slider to see the other images.





Example: Horizontal Shift


Using this parameter, you can offset the camera Field of View. For the images in this example, the following constant settings are used for some parameters: Exposure is set to Physical Exposure, F-Number is 4, Shutter Speed is 125, ISO is 100, White Balance is white.


Horizontal Shift = 0.15

Horizontal Shift = 0

Horizontal Shift = -0.15

Move the slider to see the other images.





Example: Depth of Field


To enable the DoF effect you need to turn on the Depth of Field option of the physical camera. The effect is most strongly seen when the camera is close to an object, for example when doing a macro photo. For a strong DoF effect, the camera aperture must be open wide (i.e. small F-Number value). That may lead to a very burnt and bright image, so to preserve the same illuminosity over the whole image, the shutter speed must be shortened. And last but not least, the Focus Distance of the Cinema 4D camera determines which part of the scene is actually on focus. To get the focus near, you would need a small value and inverse - a higher value for far focus.

For the images in this example, the following constant settings are used for some parameters: Exposure is set to Physical Exposure, F-Number is 2.8, Shutter Speed is 250, ISO is 100, Vignetting is 0.0, and White Balance is white.


  Depth of Field is off

 Depth of Field is on, Focus distance is 250

 Depth of Field is on, Focus distance is 400

Move the slider to see the other images.





Example: Motion Blur


To enable the motion blur effect, you need to enable the Motion Blur option of the physical camera. The amount of motion blur is determined by the speed of the moving object itself, as well as the Shutter Speed setting of the camera. Long shutter speeds produce more motion blur, as the movement of the object is tracked over a longer time. In reverse, short shutter speeds produce less motion blur.

For the images in this example, the following constant settings are used for some parameters: Exposure is set to Physical Exposure, Vignetting is 1.0, Depth of Field is on and White Balance is white.


Motion Blur is off

Motion Blur is on, ISO = 100 , F-Number = 5.6, Shutter Speed = 30

Motion Blur is on, ISO = 50 , F-Number = 5.6, Shutter Speed = 15

Move the slider to see the other images.





Example: Distortion


The difference between the Cubic and Quadratic types of distortion is slightly visible. The Cubic type should be used in some camera tracking programs like SynthEyes, Boujou, etc. For the images in this example, the following constant settings are used for some parameters: Exposure is set to Physical Exposure, F-Number is 4, Shutter Speed is 125, ISO is 100, White Balance is white.


Distortion Amount = -1, Distortion Type = Quadratic

Distortion Amount = 1, Distortion Type = Quadratic

Distortion Amount = 0

Distortion Amount = -1, Distortion Type = Cubic

Distortion Amount = 1, Distortion Type = Cubic

Move the slider to see the other images.





Example: Stereo Camera


Enabled, Side-by-side






Enabled, Top-to-bottom