14.11.2023 – Filtering and Planar Tracking

Week 7 – Filtering and Planar Tracking

Filtering

Nodes that involve pixel movement come equipped with Filtering options. Image filtering algorithms play a crucial role in defining how pixel values transform and process within the images. (It’s recommended to scale up by a maximum of 15%; exceeding this may result in blurriness.)

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Concatenation

Maintain the node order when connecting nodes, avoiding the insertion of a Grade node between Transform (or any pixel-moving) nodes, as it can disrupt concatenation. If motion blur is enabled, typically activate it at the final node to prevent interference with concatenation.

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Bounding Box

When utilizing the Merge node, the “set bbox to” knob becomes essential. Inputs outside the bounding box can affect project performance, especially during rendering. Set the bounding box using the “set bbox to” knob to keep your script efficient when merging or moving elements.

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Shuffle Node

The Shuffle node creates new channels for output and reads various layers from both internal inputs and multi-channel EXR renders, featuring multiple layers and channels per image. It allows for channel switching and removal.

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Roto and Format

When creating a Roto node, it defaults to the project’s format. When connected to another input, it adapts to the size of the connected input.

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Planar Tracker

Primarily suitable for shots with perspective shifts but not spatial movement. If an object partially blocks the view, add another planar tracker layer beside the “set a key” button, focusing on the blocked area. Ensure the Roto for the blocking object is above the layer you intend to track.

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Export Tracker

• Cornerpin (Absolute)/(Relative):
  • Absolute: Based on the format of the connected node; it shrinks the source image.
  • Relative: Based on the mask’s format for masked shots.
• Baked: An independent node not linked to the original tracker node; changes to the original tracker have no effect.

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Defocus

Use the Defocus node when you want to create a defocused effect, avoiding the Blur node for a more organic result.

ZDefocus node can also be applied using the Depth channel (note: it’s resource-intensive, so use cautiously to avoid crashes).

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Animation Tip:

• In the Curve Editor, select a keyframe and press ‘H’ to ease the curve.

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25.11.2023 added

When incorporating 3D models into Nuke, it’s advisable to use the USD format instead of FBX or 3DS, as older formats are prone to crashes.

• Convolve node: Allows blurring using shapes, including roto and text.
• Bokeh node (only in NukeX): Applies blur with accurate data from the camera.