When a molecular system moves through a trajectory, the region you want to study can drift out of view. You can pause and reposition the camera, but that interrupts the visual story and makes it harder to follow the motion continuously. In SAMSON, the Follow atoms animation can keep the camera centered on a selected group of atoms as the system moves.
What the animation follows
Follow atoms uses the atoms selected when the animation is created. As those atoms move, the camera target follows their geometric center. The camera position moves with the target, keeping the vector between the camera and its target constant. In practical terms, the view tracks the selected region while preserving its relative camera distance and orientation.
This is useful when you want to watch a moving part of a larger system—for example, a region whose trajectory would otherwise carry it away from the center of the view. Rather than manually panning along with the motion, you define the group of atoms to follow and let the animation carry the view with it.
Set up a useful follow shot
- Select the atoms first. Choose the atoms whose motion should anchor the camera. The animation follows the selection made when it is created, so make sure the selected group represents the region you actually want to keep in view.
- Set the starting view. Orient the camera and choose a comfortable distance before adding the animation. The current camera position is used at the start frame, so the initial view is part of the setup.
- Choose the start frame. In the Animator’s Track view, select the frame where the follow effect should begin.
- Add Follow atoms. In the Animator’s Animation panel, double-click the Follow atoms effect.
- Set the end frame. Choose how long the camera should follow the selected atoms. You can move the animation’s start and end frames later if the timing needs adjustment.
Taking a moment to compose the starting view is worthwhile: the camera tracks the selected atoms, but it does not choose a new angle for you. Begin with a view that makes the motion easy to interpret.
Adjusting the view and camera behavior
You can adjust camera positions with the animation controllers. The target, however, remains at the geometric center of the specified atoms. This distinction is helpful when refining the framing: you can change the camera position while keeping the selected group as the point the animation tracks.
By default, camera animations apply to the active camera. If you need to change this, inspect the animation and modify Apply to active camera. The Keep camera upwards option controls behavior that can depend on whether the grid is on or off; inspect the animation to change that setting.
When to use it
Use Follow atoms when the key task is keeping a selected region in view as it moves. If you are deciding between camera behaviors, SAMSON also provides a Look at atoms animation. Choosing the effect that matches your intended camera motion can make a trajectory easier to watch and explain.
For the full procedure and animation properties, see the Follow atoms documentation.
Note: SAMSON and all SAMSON Extensions are free for non-commercial use. Get SAMSON.