Advanced Tracking

Tracking is a very basic yet advanced effect and edit style within After Effects, that with knowledge, can be very easy to perform, but can visually look incredible, if done correctly.

First of all, make sure that the 'tracker' tab is activated, so that you can see it on the right of your screen. Next up, import the footage in which you would like to track. The best footage for tracking is anything with clear 3D visuals, and with directional movement, such as a man walking through an alleyway, or a skateboarder riding in a skateboard park. To start the tracking, within the tracker window, select track camera. This will begin analyzing the footage, and track certain points on the clip, once it is done analyzing, there should be coloured hit markers on the footage, as well as a 3D camera tracker tab on the left of the screen.

Once the footage has been analyzed, the next step is to choose an area where you want to place an object. As you hover over the coloured hit marker tracker points, a red 'target' should appear, that uses the tracked points, and connects them, so you can get a preview of what the object will look like once you have created it. Choose a position and right click on the target, and choose create solid and camera. This should now insert a coloured solid onto the position of the red target.

The next step is pre-compose the new solid layer and camera that you have created. Right click on the track solid and choose pre-compose. This will allow us to edit the contents of the solid. Choose the name for the pre-composition, and edit the contents of the track solid to your hearts content.

The below image is what I have changed the tracked solid to;

Open up the main composition again, and you will see that the tracked solid is no longer just a colour, but it is whatever contents you have within the new pre-composition. If you play the video, this pre-composition will stay on the area that has been tracked. You can alter the position of this tracked pre-composition, by changing the x, y and z rotation of the pre-composition, as well as the scale and positioning. Below I will put a video on what this can look like;

There is also an easy method to mask tracked footage. This can be used, in situations where you want a subject to be in front of a tracked pre-composition at all times, such as a person walking down an alleyway, and there is a pre-comped poster on the wall, unless you track the person walking, and make them a new layer above the initial layer, the poster will be in front of them. To begin masking, make sure the footage has been tracked. Next, click the Roto-brush tool, which is found next to the puppet pin tool. With the Roto-brush tool equipped, double click the video you want to mask from and make an outline around the desired subject.

Once the outline is made, the subject should look like this;

After this stage click back into the video, and control left arrow slowly, making sure that the Roto-brush is staying in tact throughout the movement. When you are happy with the state of the Roto-brushing, select freeze, which will analyse the Roto-brush, and will give you the finished article of the cut out subject. You can then place the subject over the tracked footage with the pre-comped posters, and the subject will now be in front of the posters.

Tracking is a very cool trick that all movie makers and music video producers should know about. I will definitely give it a good try in the near future.