This way you are giving the tracker only the static geometry of your scene to track and it is much more likely to give you a good track.īut alas, even if all goes well with the tracking, there are yet more problems that you might encounter! No Depth Information from a Tripod Pan Solve Then pre-compose the layer including the masks and apply the 3D Camera Tracker to the resulting layer. To avoid this happening, you have to first mask out any large moving foreground elements to remove them from your footage. The 3D Camera Tracker will pick up my movement and think it’s tracking the movement of a static element in your scene, a feature. Here is a screenshot of my fireworks tutorial: If you have a scene with a large moving foreground element, it can easily invalidate your tracking data. That way the 3D Camera Tracker will not track the movement of any moving objects in your scene thinking that they are fixed features. You will get the best results when you have no moving objects at all in your scene. Moving Foreground ElementsĮven if you footage is nice and crisp and there is no fast camera movement, elements in the foreground can interfere with its operation. I ended up tracking the first half and the second half of my building destruction video separately because I could not track the middle part where the camera’s movement was too fast. In this situation your only option is to re-shoot the scene or work around it. If it manages to analyse the footage and produce a cloud of 2D track points it might still fail to solve the camera if there are not enough 2D track points to infer the 3D camera movement from. If your footage includes very fast camera movement with blurry frames and undefined shapes, the 3D Camera Tracker will simply not be able to follow the movement of any features and therefore fail to analyse your footage. Even if an accidental feature was found, the camera’s movement is so fast that the feature jumps around the screen, making it impossible for the 3D Camera Tracker to follow its movement. Notice that the individual frames of the footage are extremely blurry and there are no features, no distinguishable shapes for the tracker to lock on to. Have a look at the following image sequence, taken from my After Effects building destruction tutorial.ĭuring the explosion, the cameraman dives for cover behind the concrete barrier and the camera’s movement is all over the place. There are 2 likely reasons for why that is happening! The Camera Movement is too fast You import a piece of footage, throw the 3D Camera Tracker onto the clip and then you get the following error message: One of the most common problems that people encounter is that the 3D Camera Tracker ‘just does not work’.
Now that we understand the basics of how the 3D Camera Tracker works, let’s look at the most common scenarios of why it might fail!
On the right side the size of the solved 3D track points represents how far they are from the camera. In the screenshot below you can see that the 2D track points are all the same size as they have no 3D position. It will try to infer the 3D position of these track points based on how they move as a group and then derive the movement of the camera from this data. Using this cloud of 2D track points, the 3D Camera Tracker then tries to ‘solve the camera’. This generates a cloud of 2 dimensional track points on your footage. The tracker will try to find as many features as possible in your footage and track their movement from frame to frame. Moving objects like people and cars are not features and tend to interfere with the 3D camera Tracker. A feature is a clearly distinguishable visual shape in your clip that represents a fixed location in space. The 3D Camera Tracker works by analysing your footage frame by frame and detecting features that it can track. How the 3D Camera Tracker Worksīefore we look into why the 3D camera tracker does not work, we first need to understand how it does work.
#ADOBE AFTER EFFECTS TUTORIAL HOW TO#
I have a full tutorial on how to use the 3D Camera Tracker in Adobe After Effects as a part of my 3D Integration VFX tutorial series.Īs great as the 3D Camera Tracker is, there are a number of common problems that people encounter when trying to track their footage and this tutorial will explain what is going wrong and how you can fix it. Assuming the tracking data is spot on, you can then place other visual elements in the 3D space of your scene and they will follow the movement of the camera correctly.
The 3D Camera Tracker in Adobe After Effects is a powerful tool that lets you analyse your footage and extract information about the movement of the real life camera used to film the scene.
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