When analyzing molecular structures or simulating systems over time, researchers often encounter the challenge of maintaining focus on a specific region of interest while the rest of the system evolves. Maybe you’re observing a binding site, an active center, or atoms within a critical motif, and everything around keeps moving—but your camera floats away or reorients unpredictably.
In integrative modeling with SAMSON, there’s a subtle but powerful feature that helps solve this issue: the “Look at atoms” animation. When applied, this animation keeps the camera looking at selected atoms as they move during a simulation, without changing the camera’s overall position. It’s a practical way to “anchor your gaze” while preserving context.
Why this helps
Imagine analyzing the trajectory of a ligand moving into a binding pocket. Normally, you might need to manually readjust your camera, zoom back in, or reorient the view each time the molecule drifts. This gets tedious, and more importantly, it can interrupt your ability to spot subtle interactions or spatial relationships.
With the Look at atoms animation, you can select the atoms you’re most interested in and instruct SAMSON to ensure the center of the view always stays locked on their geometric center. This helps you maintain perspective during playback and prevents you from “losing” the functional group you care about in a dynamic system.
How it works
- Select the atoms you want the camera to stay locked on. This could be a few atoms forming a residue, a metal coordination site, or any group relevant to your analysis.
- Set the current camera orientation as you would like it to look throughout the animation. This is important, as SAMSON keeps the camera position fixed and only adjusts its target point.
- Open SAMSON’s Animator (you’ll find it in the top toolbar or under Presenting > Animator), choose a starting frame, and insert the Look at atoms effect from the Animation panel by double-clicking it.
- The camera will now rotate its target to follow the selected atoms, while keeping your framing unchanged.
- Set your ending frame to define the animation duration. You can always adjust the start and end frames later.
Fine-tuning and control
If needed, you can inspect the animation to modify two key properties:
- Apply to active camera: Lets you choose which camera the animation should apply to, useful if you use multiple camera setups.
- Keep camera upwards: When checked, this makes the animation respect the current grid orientation. It helps if you want the camera to behave predictably based on whether the scene’s virtual ground plane (grid) is active or not.
You can also combine “Look at atoms” with other camera effects, such as zooming or transitioning between different viewpoints. The tool is unobtrusive, yet ensures stable and clear focus during complex structural animations.
Example
Here’s an example of the animation in action. The camera remains fixed in position but continuously looks at a group of atoms as their position changes:
To learn more about the Look at atoms animation, visit the official documentation: https://documentation.samson-connect.net/users/latest/animations/look-at-atoms/
SAMSON and all SAMSON Extensions are free for non-commercial use. You can get SAMSON at https://www.samson-connect.net.