General Focal Effects in the 3D World
Two settings provide a nice, general scene blur when using Focus: Scene Blur and Radial Blur.
Both blur the scene but in very different ways.
Although these two methods of blur are used much less frequently than the Focal Node option (more on that coming up), they can be used for a number of situations.
Scene Blur applies a general blur to the entire rendered image unless it is used with a mask.
A mask enables you to specify where the rendered image will be blurred by using the gray scale values of an image.
Darker areas are treated as transparent; lighter areas are opaque.
When using Scene Blur, the only settings that work in the Focus interface are the Focal Loss settings, as well as the Lock and Affect Alpha check boxes.
Scene Blur, like any other blurring method, offsets all of the pixels in your rendered image the distance specified in the Focal Loss settings.
Because sometimes you might want to blur a background while keeping your foreground sharp, this is a useful and quick option.
Radial Blur creates a blur from the center of the image outward.
This is where the hot spot/falloff thinking pays off.
With Radial Blur, you need to use both the Focal Range and Focal Limit settings.
With only a little difference between both Focal Range and Focal Limit, you see a noticeable "edge" between focused and blurred.
For best results, use a larger difference.
Set the Focal Range to approximately 10 and the Focal Limit to approximately 100 to 130.
This produces a nice soft-corner blur that is good for dream sequences or Abyss-like effects.
Furthermore, animating these two values can be an eye-focusing experience.
With proper Focal Range and Focal Limit settings, you can get nice, "soft" corners on your renderings.
Both Radial and Scene Blur happen in 2D space, and do not rely on the Z-Buffer to produce their result.
This means that Focal Range and Focal Limit are 2D parameters.
When used with the Focal Node setting, they become 3D parameters.
The blurring effect tends to look a little more realistic if you unlock Horiz.
and Vert.
Focal Loss and adjust the entries to something nearer to the aspect ratio of the rendered image size.
Rounding off to a Width:Height ratio of 2:1 is a good starting point.
Both blur the scene but in very different ways.
Although these two methods of blur are used much less frequently than the Focal Node option (more on that coming up), they can be used for a number of situations.
Scene Blur applies a general blur to the entire rendered image unless it is used with a mask.
A mask enables you to specify where the rendered image will be blurred by using the gray scale values of an image.
Darker areas are treated as transparent; lighter areas are opaque.
When using Scene Blur, the only settings that work in the Focus interface are the Focal Loss settings, as well as the Lock and Affect Alpha check boxes.
Scene Blur, like any other blurring method, offsets all of the pixels in your rendered image the distance specified in the Focal Loss settings.
Because sometimes you might want to blur a background while keeping your foreground sharp, this is a useful and quick option.
Radial Blur creates a blur from the center of the image outward.
This is where the hot spot/falloff thinking pays off.
With Radial Blur, you need to use both the Focal Range and Focal Limit settings.
With only a little difference between both Focal Range and Focal Limit, you see a noticeable "edge" between focused and blurred.
For best results, use a larger difference.
Set the Focal Range to approximately 10 and the Focal Limit to approximately 100 to 130.
This produces a nice soft-corner blur that is good for dream sequences or Abyss-like effects.
Furthermore, animating these two values can be an eye-focusing experience.
With proper Focal Range and Focal Limit settings, you can get nice, "soft" corners on your renderings.
Both Radial and Scene Blur happen in 2D space, and do not rely on the Z-Buffer to produce their result.
This means that Focal Range and Focal Limit are 2D parameters.
When used with the Focal Node setting, they become 3D parameters.
The blurring effect tends to look a little more realistic if you unlock Horiz.
and Vert.
Focal Loss and adjust the entries to something nearer to the aspect ratio of the rendered image size.
Rounding off to a Width:Height ratio of 2:1 is a good starting point.
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