Outside-in tracking is a Tracking term in filmmaking. In virtual production, the nuances of this term take on special meaning. Here, we break down the definition to give you a starting point.
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Outside-in tracking is a method of camera and object tracking used in virtual production that requires cameras or sensors to be mounted around the perimeter of a volume. This type of tracking is necessary for accurate recording, analysis, and replication of movement within the volume space. Outside-in tracking is often seen in animation, visual effects, motion capture, and 3D scanning applications as it allows for more precise data regarding an object’s movements.
The process of outside-in tracking involves the use of multiple cameras or sensors surrounding the target area. The cameras are synced together to track the movements of both the camera itself and any objects placed inside the designated space. The information gathered by these cameras then goes through software which reads and interprets the data before it can be utilized.
VFX supervisors, animators, and other creative professionals involved with virtual production projects are usually responsible for implementing outside-in tracking techniques into their workflows. It’s important that they understand how this kind of tracking works and its various benefits. With good outside-in tracking, accurate positions and velocities can be measured over time, allowing users to replicate and analyze movement more accurately. Additionally, when using an array of cameras, more sophisticated lighting models and texture detail can be produced compared to using only one camera.
To ensure successful results from outside-in tracking in a virtual production workflow, there are some best practices one should follow. First off, it's important to remember that accuracy relies heavily on correctly calibrating all cameras being used in the system. As such, it's also essential to ensure that each sensor has enough physical distance from the other so that there won't be interference between them. Lastly, ensuring adequate light levels in the environment will help prevent shadows cast onto the tracked objects from blocking out vital information needed for measurement.
Overall, outside-in tracking is a handy tool in virtual production due to its ability to measure and record accurate position data of both cameras and objects. When utilized properly, this method enables users to create more detailed visuals while ensuring accuracy is not sacrificed.