Nuke Import

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Exporting from Autoshot #

The initial step is the usual step of syncing takes from Jetset to the user’s local machine and selecting a take to process. This is the same as is covered in the Blender and Unreal Autoshot tutorials.

Setup and Script Export #

In Autoshot:

Under Run Values/Program, choose ‘Others’
Set the Clip In and Clip Out frames to specify which frames you want to extract.
Make sure to select the Scene Locator that was used in the take to have the 3D tracked camera and scene scan mesh show up in the correct position in Nuke’s 3D coordinate space.
Set the camera manufacturer and color space of the source clip. All Autoshot EXR files are automatically converted to ACEScg.
You can specify an AI matte processor if you want mask shapes for the human figures in the footage.
Next, hit Save and Run.

Autoshot will then run the EXR file extraction and write out a python file into the /nuke directory under the created sequence directory.

To find this directory, click the ‘Open’ button next to the selected take in the Take dropdown selector. This will open a File Explorer to the correct directory.

To run this script in Nuke, go to File ->Run Script and navigate to the /nuke directory above, then choose the generated .py file.

The script will generate a node group. Nuke Non-Commercial and Nuke Indie are limited to 10 nodes per Python script run, but the essential nodes are all there:

EXR loader for the camera footage EXRs in ACEScg format
EXR loader for the Undistort STMap generated by Jetset Cine’s lens calibration
A loader for the 8 bit grey scale AI Mattes (if generated)
STMap node to undistort the camera footage
An Axis node with the position and orientation of the chosen Scene Locator
A ReadGeo node to read the scanned mesh in, and a Wireframe node to set it to wireframe.
A Camera node with the animated track associated with the camera frames
A Scanline Render node to see the combined 2D/3D join
A Write node pre-configured to write to the /compEXR and /compJPG directories for saved EXR and JPG proxy renders

Verifying Project and Footage Color #

Double clicking the camera original footage node will bring up the Loader panel, where you can confirm that the footage is being correctly interpreted as ACEScg:

Hit L on the keyboard to play through the footage and verify the tracking match:

The automatic Jetset Cine track is not a sub-pixel track, but it’s workable for many shots that don’t have a lot of ground contact.

For shots with ground contact, in our next tutorial we’ll work through a method in Nuke to refine our camera solve without losing our 3D spatial coordinates.