TABLE OF CONTENTS

• Inputs
• Parameters
• Lens Tab
• Optical Artifacts Tab
• Kernel Tab
• Corrective Slices Tab

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.