TABLE OF CONTENTS
Inputs
Input
The input image, this can include any number of channels and layers - if true Z defocus is required one of the channels should contain the Z depth information.
Kernel
An optional input image that represents the shape of the defocus kernel. Although any image can be used it is most effective when reference stills have been created for the lens in question. This is usually achieved by rolling a few frames of a pin light shining directly into the lens in question.
Camera
An optional Nuke 3d camera that is used to override the focal plane, aperture etc. of the Bokeh node.
Deep Input
An optional Deep Data input, this can be just deep opacity values or full RGBA data. Although you’ve attached a deep input the plug-in still requires a main input, if you have just deep data it’s recommended that you use a DeepToImage and use the output of that.
Mattes
An optional input that can be used to control various parameters with an image matte.
Parameters
Bokeh Channels
Used to select the desired channels/layers to apply the defocus effect too.
Depth Channel
Used to select the desired Z channel, by default this is depth but any can be used.
Output Type
Varying output types:
- Defocused Image - the defocused image
- Lens Bloom - just the lens bloom, lens blooming has to be on
- Focal Distance Visualization - preview the actual focus distance and in/out of focus areas
- Filter Shape - a preview of the shape used for the kernel
- Focus Matte - mattes for the in/out of focus areas
Focus Region Output
Used to limit the rendered output to all, front or back focus.
Multiplier, Front Multiplier, Back Multiplier
Used to control the scale of the defocus effect, multiplier is ignored when real world lens has been selected but both front and back are utilized.
Depth Style
Depth values are stored in a variety of ways, this lets you select how Bokeh interporates z values of the input image ( this is not relevant for deep inputs ).
- Real - real world values, leave them as they are
- 1/z - inverted values, Bokeh will use the reciprocal
Focal Plane
The plane in focus.
Focus Region Size
Only available when real world lens is turned off, this expands the region in focus.
Focus Region Falloff
Controls how the effect falls off over the depth.
Defocus Matte Channel
An optional matte channel ( supplied via the Mattes input ) to modulate the defocus amount
Normalize Visualization
Used to normalize the output values when Visualize Depth is used
Integrate Deep Front and Back Separately
In some cases artifacts can arise from integrating all the slices together, this will separate the front and back focus areas and integrate them separate to help avoid these.
Lens Tab
Real World Lens Simulation
Turning on Real World Lens Simulation gives you control over the focal length, f-stop and other parameters required to match physical lens characteristics.
Focal Length
Focal length of the lens.
Aperture
Aperture or f-stop of the lens.
World Scale
The scale of the world units, you should set this to the scale provided by CG renders - Maya generally defaults to cm.
World Scale Multiplier
This is used as a multiplier on top of the world scale, as an example - if your scene units are based on 10cms then you can set the World Scale to centimeters and this parameter to 10.
Film Format
Presents used to set the desired filmback, this will set the correct aperture width and height for the selected format. Custom can be used to enter your own values.
Aperture Width and Height
Automatically set by the Film Format selected above, it’s possible to override via Custom if a desired format isn’t available.
Optical Artifacts Tab
Bloom
Will cause bright values in the input image ( defined by the bloom threshold ) to create a brighter lens bloom.
Curvature
Used to define how much lens curvature there is, this will modulate the Bloom based on where in the lens the light is entering the lens.
Bloom Threshold
Determines how bright the input must before before blooming is applied, by default this is 0.7 which means any input values above that will cause a blooming effect.
Bloom Matte Channel
An optional matte channel ( supplied via the Mattes input ) to modulate the level of lens Bloom.
Spherical Aberration
Control the spherical aberration of the lens.
Chromic Aberration
Introduce chromic aberration artifact into the defocused image.
Chromic Aberration Offset
Used to adjust the refraction offset of each colour for the chromic abberation.
Chromic Aberration Matte Channel
An optional matte channel ( supplied via the Mattes input ) to modulate the level of Chromic Aberration
Kernel Tab
Kernel Type
- Input - use the supplied input image as the kernel
- Aperture Blades - render a kernel that mimics the blades of an aperture
- Circular - render a circular/disc shaped kernel
Maximum Kernel Size
The maximum size a kernel is allowed to be, this can be used to optimize renders if need be at the expense of clamping the defocus effect. It’s rare that you would actually need this.
Aspect Ratio
Provides the means of controlling the aspect ratio of the Bokeh, this is useful for matching anamorphic effects
Softness
How soft the generated kernel will be.
Sides
The number of actual aperture blades, or “sides” of the shape.
Rotation
Rotation of the polygonal kernel.
Corrective Slices Tab
Corrective Slices
Artifacts are common in post processing effects that rely on depth due to the difference in fidelity and filtering between the Z depth and RGB images generated by most rendering applications. One of these artifacts is how a final image is composited due to varying depth values - as you can see in the image provided below it appears that the second sphere eats into the first.
Bokeh provides a means of correcting this by managing how the images depth values are composited - the volume that is sliced is defined by the focal plane and the focus region size.
By adjusting the Corrective Slices value it’s possible to remove most signs of the artifacts.
Be aware that due to the nature of this corrective stage the over all Bokeh level may need to be increased to return to the desired effect.
Override Near/Far
If selected the parameter below can be used to define the exact volume to be sliced vs. inferring it from the focal plane and region size.