When visualizing molecular trajectories or complex conformational changes, it’s often necessary to focus on a specific part of the system that changes position over time. However, manually adjusting the camera to keep that part in view during a dynamic simulation can be tedious and imprecise.
This is where the Follow atoms animation in SAMSON can save a lot of effort. It allows you to lock your camera onto selected atoms so that their motion naturally drives the movement of the camera — no manual adjustment needed.
Why this helps
Imagine you’re observing a ligand entering a binding pocket across a molecular dynamics trajectory. If the ligand drifts across the simulation box, you either lose sight of it or spend time dragging the view manually. Rather than constantly re-centering your camera, the Follow atoms animation will keep your view aligned with the moving ligand (or other atoms of interest). This keeps your focus on what matters and ensures smooth, consistent visualization.
How it works
When the Follow atoms animation is applied in SAMSON’s Animator, the camera’s position and its target are updated across frames to follow the geometric center of the selected atoms. This keeps a constant distance and orientation between the camera and the moving system part.
Here’s a basic workflow to use it:
- Select the atoms you want the camera to follow (e.g., a ligand, functional group, or flexible domain).
- Set your preferred point of view (rotate, zoom, etc.).
- Choose the start frame in the Animator’s Track view.
- Insert the Follow atoms effect from the Animation panel by double-clicking it.
- Define the end frame for the animation to control its duration.
SAMSON keeps the camera’s relative orientation fixed, so the visual perspective remains stable while atoms move. This way, you retain your original view intent (e.g., front, side, diagonal) even as the atoms change position during the simulation.
Tips and adjustments
If you’re not satisfied with the automatic camera path, you can fine-tune it. The start and end frames can be dragged on the timeline to adjust the animation’s timing. Additionally, the camera position can be edited without disrupting the following behavior — the camera target remains on the group’s geometric center.
Advanced users can also toggle whether the camera stays upright depending on whether SAMSON’s grid is enabled, using the Keep camera upwards option in the Inspector. This can help avoid disorienting tilts during the animation.
Use cases
Follow atoms is useful for a variety of scenarios:
- Tracking mobile species in molecular dynamics simulations.
- Visualizing conformational shifts in moving protein domains.
- Focus animations for presentations and educational videos.
If your goal is to guide the viewer’s attention or create polished animations, this feature simplifies the process.
To learn more technical details and explore links to other camera-related animations (like Look at atoms), visit the full documentation: https://documentation.samson-connect.net/users/latest/animations/follow-atoms/
SAMSON and all SAMSON Extensions are free for non-commercial use. You can download SAMSON at https://www.samson-connect.net