38.1 Camera Tracker in Nuke

This guide will walk you through the basic setup of the Camera Tracker in NukeX



Preparing Footage

If your footage is a video file such as MP4, it’s recommended to convert to image sequence first

Image sequences are reliable, the conversion is fast

Write JPEG Sequence

Copy the name of the source footage and add .####.jpg

Set the JPEG quality to 1

Unless you’re dealing with a grainy low-light shot, JPEG is ok for tracking


Project Settings

Edit menu > Project Settings or Hotkey S

Before we start, confirm your Project Settings

Size and range follow your footage, frame rate your global project settings


Camera Tracker

Add the Camera Tracker node

NukeX required

Tracker Setup

Range: Global is the range of Project Settings
Use Custom if you don’t want to track the entire range

More frames will take longer but often give better results because we get more information

Lens Distortion: Set to Unknown Lens and tick Undistort Input

Film Back Preset: This is important to set correctly. Google Image Sensor Size of your camera, a smartphone camera is just a few millimeters

I shot on Canon 5D MarkIII

Refining Settings

Open the Settings tab

Tick Preview Features

Number of Features: I pushed them up

Detection Threshold: If too many features are in clouds or other areas making little sense, bring the value up and monitor


Hit Track to start tracking, this may take a while

Track Result

Our result shows enough long tracks

If you expected more or different features, first re-visit the Number of Features and Detection Threshold and track again

Or you could also add UserTracks


Next, hit Solve to start the camera solving

Solve Result

The result shows the track trails indicating length and quality

green (good)
orange (maybe)
red (rejected)

Solve Result Detail

Detail information of individual tracks by hovering over one

Error Value

Error under 1 is great

Between 1 and 2, I will continue and test closely

Over 2, not good, definitely visit Improving Solve section further below


Export Scene+

Tick Link output, Select Scene+ and Create the scene

3D Scene

We get a basic setup with the 3 nodes every Nuke 3D scene needs: Scene, ScanlineRender and Camera

In addition, we also get: PointCloud and LensDistortion

Camera and LensDistortion are linked to CameraTracker node

Navigate the Scene

Connect the Scene node to the Viewer, should automatically switch to 3D view, else use TAB key to toggle or View Selection drop-down

If you’re lost, select Camera, hit hotkey F in viewer

Most important hotkeys are:

MMB (or Alt+LMB): Translate Viewer perspective
Wheel (or Alt+MMB): Zoom Viewer perspective
Ctrl+LMB (or Alt+RMB): Rotate Viewer perspective

List of all Nuke Hotkeys > 3D Viewer

Improving Solve

Adjusting AutoTracks can improve the overall Solve Error value. Based on track length or error values, you can specify which tracks contribute and which should be rejected

Min Length

Open AutoTracks tab

Check your current Solve Error

Select pair track len – min and Min Length

Use Min Length slider to cut off values, while monitoring result

Monitor Result

While moving the Min Length slider to cut-off values, the rejected tracks turn red

Max Track Error

Select pair error – rms and Max Track Error

Use Max Track Error slider to cut off values

Again, monitor which tracks turn red and will be rejected

Max Error

Select pair error – max and Max Error

Use Max Error slider to cut off values

Monitor which tracks turn red

Monitor Result

A lot of tracks turned red, do we need any of these urgently? Did we cut-off too many?

Shuffle through the clip and double-check that enough green tracks are left at all times

Delete Rejected

To trash all red tracks for good, use both Delete Unsolved and Delete Rejected

Monitor Result

The immediate effect: All red tracks are gone

Solve Error Value

Check the Solve Error value: Down to 1.22

Hopefully, this helped to improve your track