Additional Features of the Physical Renderer
Open the following Project before starting with this section:
Of course the Physical Camera can also be used to create animations, which brings an additional type of blur into play: Motion Blur. Whenever an object moves quickly through a scene it blurs to a certain degree, depending on its velocity and the degree to which the rotating shutter affects incoming light. The rotating shutter is a disc with an opening. The disc rotates and allows light to hit the film at regular intervals. The f-stop speed for an animation will correspond to a photo camera’ f-stop speed for still images. This effect must also be enabled in the Edit Render Settings menu (the sample quality has a major influence on render time so experiement with different settings).
Enable the Camera’s Movie Camera option. Now Shutter Angle, Shutter Offset and Shutter Efficiency can be defined instead of Shutter Speed (s). Shutter Efficiency in particular can be viewed as an equivalent of the Shutter Speed (s) setting. The greater the value, the more light that will fall onto the film and the stronger the motion blur effect will be.
For this Project, simply enabling Motion Blur and Movie Camera is enough to achieve the desired result. Because this effect is designed for animations and the Viewport can only display the current state when the Project is rendered, you have to select the
This effect lets you simulate lens distortion for your Camera. Reload the file from the beginning of this section, set the F-Stop value to 8 so the image does not render to brightly and set Lens Distortion - Quadratic to 20%.
The effect will be calculated differently, depending on whether you set your value to Quadratic or Cubic. These settings offer very similar results and it’s up to you which of these settings you use.
Use the Vignetting Intensity value to darken your image circularly towards the image edge. To do so, remove any Lens Distortion and set Vignetting Intensity to 80%.
The second vignetting option, Vignetting Offset, lets you move the Vignetting Intensity outward, which will cause the darkening to be reduced somewhat. Set the value to 50% and see what happens.
This effect simulates a color offset to the image’s edge. The refraction in the camera lens will create a blurred image edge. Hence, you must enable the Depth of Field in the Edit Render Settings menu again. You should also set the Vignetting values back to 0% so the effect can be seen and does not appear too dark.
Set CA to 75% and define a fitting F-Stop and Shutter Speed (s) so the color offset can be seen in the blurred foreground. Values of 4 and 0.004, respectively, should produce a good result.
In order to make the effect more apparent, set Sampling Quality to
This effect also takes place in blurred regions of a rendered image. A shape can be defined for the F-Stop’s lens effects. In order to make the effect visible, set Chromatic Aberration to 0 and you can define the number of edges via the Blades value or a shader via the Shader option. Below are a few examples with Blades set to 6 and 3, respectively as well as with a Galaxy shader.