How to use VRayPhysicalCamera

This tutorial show you the example function of vrayphysical cam.

Example 1: exposure control - f-number (f-stop)

This 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 DOF effect, see Example 9.

Exposure is on, Shutter speed is 60.0, ISO is 200, Vignetting is on, White balance is white. 

f-number is 8.0	f-number is 6.0	f-number is 4.0

Example 2: exposure control - Shutter speed

This parameter determines the exposure time for the virtual camera. The longer this time is (small Shutter speedvalue), the brighter the image would be. In reverese - if the exposure time is shorter (high Shutter speed value), the image would get darker. This parameter also affects the motion blur effect, see Example 10.

Exposure is on, f-number is 8.0, ISO is 200, Vignetting is on, White balance is white.

Shutter speed is 60.0	Shutter speed is 30.0	Shutter speed is 125.0

Example 3: Exposure control: film speed (ISO )

This parameter determines the sensitivity of the film and so the brightness of the image. If the film speed (ISO) is high (film is more sensitive to the light), the image is brighter. Lower ISO values mean that the film is less sensitive and produces a darker image.

Exposure is on, Shutter Speed is 60.0, f-number is 8.0, Vignetting is on, White balance is white.

ISO is 400	ISO is 800	ISO is 1600

Example 4: Zoom factor

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

Exposure is on, f-number is 8.0, Shutter speed is 60.0, ISO is 200.0, Vignetting is on, White balance iswhite

Zoom factor is 1.0	Zoom factor is 2.0	Zoom factor is 0.5

Example 5: Vertical shift (Camera Correction)

Using this parameter you can archive the so called "2 point perspective". To have that done automatically, use the Guess vertical shift button.

vertical shift: Guess (2 point)	vertical shift: -0.5	vertical shift: 0.5

Example 6: Distortion

The difference between the two types of distortion is slightly visible. The Cubic type should be used in some camera tracking programs like SynthEyes, Boujou etc.

Distortion is 1.0, Distortion type is Quadratic	Distortion is -1.0, Distortion type is Quadratic
Distortion is 1.0, Distortion type is Cubic	Distortion is -1.0, Distortion type is Cubic

Example 7: Vignetting

This parameter controls the simulating the optical vignetting effect of real-world cameras.

Vignetting is 0.0 (vignetting is disabled)	Vignetting is 1.0

Example 8: White balance

Using the white balance color allows additional modification of the image output. Objects in the scene that have the specified color will 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.

Exposure is on, f-number is 8.0, Shutter speed is 200.0, ISO is 200.0, Vignetting is on

White balance is white (255,255,255)	White balance is blueish (145,65,255)	White balance is peach (20,55,245)

Example 9: Depth Of Field (DOF)

To enable the DOF effect you need to turn on the Depth-of-field option in the Sampling rollout of the physical camera. The effect is most strongly seen when the camera is close to some object, like 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 shortened. And at last but not at least the focus distance determines which part of the scene will be actually on focus. To get the focus near, you would need a small value and reverse - higher value for far focus. 

Exposure is on, f-number is 1.0, Shutter speed is 4000.0, ISO is 200.0, Vignetting is on

DOF is off	DOF is on, Focus distance is 400	DOF is on, Focus distance is 4000

Example 10: Motion Blur (MB)

To enable the motion blur effect you need to turn on the Motion blur checkbox in the Sampling rollout of the physical camera. The amount of the 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 will produce more motion blur, as the movement of the object is tracked over a longer in time. In reverse, short shutter speeds will produce less motion blur effect. Keep in mind that to preserve the same illuminosity over the whole image, the f-number value has to be corrected as well.

Note that in the example the far object is moving quicker than the near one, which cases the difference in the motion blur effects.

Exposure is on, ISO is 200.0, Vignetting is on

Motion blur is off	Motion blur is on, f-number is 16.0, Shutter speed is 30.0	Motion blur is on, f-number is 8.0, Shutter speed is 125.0