Working with ASC-CDL and 3D-LUT

figure 1: The LiveGrade Grading Panel

figure 1: CDL and LUT grading panel

The CDL Grading Mode offers ASC-CDL controls for the use in a wide range of workflows. CDL Grade can be used with Rec.709 signals. To be used with other signals LiveGrade allows to import 3D LUTs of choose from 3D LUT Presets e.g. for custom log-to-video conversions.

In order to support workflows that apply CDL in log gamma as well as in video gamma, the order of LUT and CDL filters can be changed when using the CDL Advanced grading mode.

The color controls for the CDL and LUT grading mode consist of:

  • ASC-CDL controls node:
    • RGB Shadows, Mid-tones and Highlights color wheels

 

figure 2: ASC-CDL controls

figure 2: ASC-CDL controls

ASC-CDL files can be directly loaded and saved to/from the CDL node (supported format: *.cdl).  Click the gear button on the left side of the CDL node and select if you want to load or save a CDL.

Please be aware that the ASC-CDL specification always includes a saturation value. When one saturation node is present CDLs will be loaded and saved from/to the present saturation node. When multiple CDL and saturation nodes are present you will be pointed choose the saturation node you want to load the saturation to (indicators A,B,C etc.).

  • Import of 3D LUT node: The grading mode “CDL Grade” can import 3D LUTs and CDL files and can export ASC-CDL files.
    • 3D LUT Import options with averaged curve displays for each channel

 

figure 4: 3D LUT node

figure 3: 3D LUT node

  • Saturation slider node
figure : Saturation node

figure 4: Saturation node

Linked Looks

You may have noticed that on the right side of each node in the grading panel a chain symbol appeared. It indicates the synchronization state of the node:

  • Blue chain button: Node is synced between linked slot (indicated with a red frame)
  • Grey chain button: Node is unsynced between linked slots and therefore controlled independently (indicated with a grey frame) 

It’s possible to switch the linked state of a node by clicking on the chain buttons. For more detailed information about the node synchronization, please check the article Linked Looks in LiveGrade Pro.

 

Use cases

Some example use cases for camera/workflow setups:

Use case A: CDL support for Rec.709 camera

  • Setup: Input for LiveGrade – Rec.709 signal from camera.
  • Filtering: ASC-CDL is applied on SDI-signal  in video gamma.
  • Workflow: Export of ASC-CDL XML files for exchange with dailies system or post.

Use case B: Predefined look with 3D LUT

  • Setup: Input for LiveGrade – Signal from camera, 3D LUT with predefined LUT loaded in 3D LUT panel from colorist / post.
  • Filtering: Look refinement with ASC-CDL controls.
  • Workflow: Export of refined 3D LUT file for exchange with dailies system or post.

Use Case C: Creating a custom tone mapping 1D LUT

  • Setup: Input for LiveGrade – Signal from camera
  • Filtering: Creating a 1D LUT with the curve editor.
  • Workflow: Export as 3D LUT

Use case D: Alexa Log-C with CDL support (log – or video-workflow)

  • Setup: Input for LiveGrade: Log-C signal from ARRI Alexa; load ARRI Log-C to Rec.709 LUT in LUT panel of CDL Grade mode. Always use the “EE” variants of 3D LUTs from the ARRI LUT Creator.
  • Filtering: Depending on the order of filter panels the ASC-CDL is applied on SDI-signal  either in Log-C or in video gamma.
  • Workflow: Export of ASC-CDL XML files or combined 3D LUT for exchange with dailies system or post.

Use case E: Sony S-Log with CDL support (log – or video-workflow)

  • Setup: Input for LiveGrade – SLog signal from Sony camera (e.g. PMW-F5/F55); load Sony SLog to Rec.709 LUT in LUT panel of CDL Grade mode.
  • Filtering: Depending on the order of filter panels the ASC-CDL is applied on SDI-signal  either in SLog or in video gamma.
  • Workflow: Export of ASC-CDL XML files or combined 3D LUT for exchange with dailies system or post.

For more information about  grading modes of LiveGrade, please see “Grading Modes in LiveGrade”.

 

Please note: The documentation is currently in transition from LiveGrade Pro version 3 to version 4 and may not be up to date yet.