Choose a lens in millimetres, apply editable shot motion, guide a camera along a path, and model against an edit-only reference.
Where: Open a Scene 3D editor → camera inspector / scene assistant / reference backdrop controls.
Key ideas
- Lens is a view of the existing camera: Lens and Focal length controls translate millimetres into the camera’s stored field of view. They do not create a second independent camera parameter that can drift away from FOV. Changing either view updates the same camera.
- Presets author real keyframes: The shot library resolves relative movement against the current camera or object pose and writes editable keys into the cinematic timeline. Camera presets require a camera target; object presets require a scene node. The target is validated before motion is applied.
- Reference is not rendered content: The reference backdrop is an edit-only modeling aid with image, opacity, fit, and visibility controls. It is hidden in cinematic mode, renders, and exports. The Flowgen AI reference socket supplies assistant context; it is not automatically a visible scene plane or environment light.
Steps
- Open the actual scene and inspect the existing cameras, nodes, and animation before asking for another move. The scene reader now includes live keyframes so later edits can avoid stacking conflicting motion.
- Select the camera and choose a Lens preset—14, 24, 35, 50, 85, or 135 mm—or enter a Focal length. Inspect the framing in the camera view.
- Ask the scene assistant for a named move. Through MCP, select the Scene3D host element in the document, then call apply_motion_preset with the preset id and real cameraId or nodeId. The bridge pins the host scene; do not pass the Flowgen node id as a scene-internal target.
- Set durationSec, startSec, and amount when the natural preset timing or distance needs adjustment. Keep mode=replace unless you intentionally want to merge into existing keys.
- For a rail move, create a guide path and bind the camera or its aim using the camera-path operations exposed by edit_scene. Do not substitute a swept tube: a rail is a non-surface path, not visible geometry.
- Add a Reference image in the backdrop controls, adjust Opacity and Fit, and use Show to hide it when comparing the modeled scene without assistance.
- Play and scrub the cinematic timeline, inspect the resulting keyframes, then check a render/export to confirm the edit-only backdrop is absent.
Camera and object preset reference
- Camera moves: dollyIn, dollyOut, orbit, turntable, arcShot, craneUp, craneDown, dollyZoom, handheldDrift, whipPan, pullBackReveal.
- Object moves: riseAndSettle, floatBob, objectSpin, popIn, spinReveal.
- amount=1 uses the authored movement; smaller values make it subtler and larger values extend it.
- replace clears only the channels the preset drives before writing; merge is an explicit choice to retain existing keys.
- keyframe_scene supports per-key easing and also defaults to replacement. Constant-speed loops should remain linear so their seam does not stutter.
Reference backdrop controls
- Reference selects the image; remaining controls appear after a source is set.
- Opacity changes how strongly the guide shows during editing.
- Fit selects the supported image framing mode.
- Show toggles Visible while editing versus Hidden.
- An edit-only backdrop is not a render background, HDRI, or output texture.
Flowgen and MCP access
Use open_node_editor for the scene node, then enumerate document tools. Select the Scene3D host element or use the sole scene; an ambiguous selection is refused. Begin inspect_scene with section=index, then section=animation before changing keyed motion. apply_motion_preset uses real camera/node IDs from that scene. Keep the editor open while operating it and close_node_editor to save. Deselecting the Flowgen node no longer implicitly exits its 3D session or kills the assistant.
Troubleshooting
A preset reports the wrong target kind.
Use cameraId for a camera move and nodeId for an object move. Read the current scene rather than inventing identifiers.
The camera path renders as a tube.
Create a guide path, not a swept mesh. Camera-rail operations depend on a path guide.
The reference image is missing from export.
That is intentional. Add actual scene background/geometry if the image must appear in the final output.