Camera Effects

Introduction

The Krakatoa renderer provides two camera effects - Motion Blur (temporal blurring along the motion vector), and Depth Of Field (spatial blurring based on camera parameters).

Motion Blur

  • The native Krakatoa Motion Blur effect uses the Position and Velocity data of the loaded particles to interpolate a user-defined number of samples within a specified Shutter interval with either equal spacing or using jittering along the path. The resulting passes are then composited together to produce the final image.
  • The illumination of the particles is currently performed only once, at the center of the Shutter interval.
  • The Shutter interval is defined in degrees and defaults to 180.0, but can be set to extreme values beyond 360.0 to produce exaggerated Motion Blur effects.
  • A Bias value can be used to shift the Shutter Interval’s timing. The default value is 0.0 (no bias), with the Shutter interval centered at the frame.
  • By default, the motion of the camera will be taken into account when blurring the particles.
  • An option to ignore the camera motion lets you perform only particle motion blur.

Depth Of Field

  • The Krakatoa Depth Of Field effect calculates the disk area a single particle would occupy based on the current camera settings and then draws this particle multiple times (depending on the settings dozens or even hundreds of times) at random positions within that area.
  • This means that if Krakatoa had to render one million particles and the Depth Of Field settings require each particle to be drawn on the average 10 times (some more, some less, depending on their distance to the camera), the renderer would have to draw 10 million particles.
  • Thus, while drawing points is relatively inexpensive, using Depth of Field with high quality settings or extreme lens settings could cause significantly longer render times.
  • The quality of the Depth of Field effect depends mainly on the Depth of Field Sample Rate value found in the Main Controls rollout. This value scales the amount of samples used per particle. The default value of 0.1 is very low quality but usually adequate for testing. A value of 1.0 is relatively high quality and can take a bit longer to calculate. Values close to 0.0 like 0.001 will jitter the actual particles around without doing coverage of the area and could be used for very quick previews.