Quick answer: A one-frame “wrong angle” at a Sequencer cut almost always comes from a camera whose transform is not keyframed at the cut time, or a possessable vs spawnable mismatch that forces Sequencer to display the camera’s default pose for one tick. Keyframe transforms on every cut, commit to spawnable-or-possessable for each camera, and inspect the Camera Cut track for overlapping sections.

You are editing a cinematic and everything looks fine in the Sequencer preview. You render a movie or hit PIE, and on one cut — always the same one — the camera briefly shows a completely wrong angle for a single frame before snapping to the intended view. It feels like a bug in the engine, but it is almost always a content issue with a very specific cause.

How Sequencer Picks a Camera

Sequencer uses two independent mechanisms. The Camera Cuts track chooses which camera renders at each time. A Cine Camera track (or a plain Camera track) animates the properties of a specific camera actor. The two tracks must be consistent with each other: if the Camera Cuts track selects CineCamera_B at frame 240, then frame 240 must also have valid transform keyframes on CineCamera_B’s animation track.

When the transform is missing, Sequencer falls back to whatever pose the camera actor has in the level. For a possessable camera, that is wherever the artist left it in the viewport. For a spawnable camera, that is the default transform baked into the spawnable template — usually 0,0,0. Either way, you get a one-frame flash before the next keyframe takes effect.

Keyframe the Transform at Each Cut

Open your sequence and find the first cut that misbehaves. Select the target camera in the Outliner (or in the Sequencer binding list), scrub to the frame where the cut occurs, and press S to add a full transform keyframe. Do this at the cut frame itself, not one frame before or after. Sequencer evaluates the cut at the exact integer frame; a keyframe at 239 or 241 leaves frame 240 interpolating from whatever came before it.

You can automate this for a whole sequence with a brief Python script:

# fix_camera_cuts.py - add transform keys at every Camera Cut section start
import unreal

sequence = unreal.EditorAssetLibrary.load_asset(
    "/Game/Cinematics/LS_Intro.LS_Intro")
tracks = sequence.get_master_tracks()

for track in tracks:
    if not isinstance(track,
            unreal.MovieSceneCameraCutTrack):
        continue
    for section in track.get_sections():
        cut_time = section.get_start_frame()
        binding = section.get_camera_binding_id()
        # Add a transform key on the bound camera at cut_time
        print(f"Cut at frame {cut_time} -> binding {binding}")

Extend the script to add keys via movie_scene_3d_transform_track, or simply use this output to walk the timeline manually. Either way, every cut-frame gets an authoritative pose.

Spawnable vs Possessable

This is the bug most people never spot. A possessable camera is one that exists in the level and is referenced by the sequence. A spawnable camera is instantiated by the sequence itself at runtime. If you create a camera with the +Camera button in Sequencer, it is usually spawnable. If you drag a camera from the Outliner into Sequencer, it is usually possessable.

When you have both kinds in the same sequence and they share a Cine Camera track (for example, because you duplicated a binding), the evaluator may briefly render the wrong instance at the cut boundary. To diagnose, right-click each camera in the Sequencer binding list and read the tooltip. Spawnables have a lightning-bolt icon; possessables do not. Pick one model and stick to it across a single sequence. To convert a spawnable to a possessable (or vice versa), right-click the binding and choose Convert Selected Spawnable to Possessable.

Camera Cut Track Sections

Open the Camera Cuts track at the top of the sequence. Sections should be contiguous — the end of one cut is the start of the next. Gaps (even one frame) produce a moment where no camera is selected and the engine falls back to the previous viewport camera, which can briefly show the world from the editor camera’s perspective. Overlaps (two sections both claiming the same frame) create a race where the evaluator may pick either camera.

Scrub along the Camera Cuts track and look at the section edges. Right-click any suspicious edge and choose Snap To Frame. Then widen the track panel vertically so any stacked sections become visible — accidental duplicates are easy to miss if they visually overlap.

Camera Lock and Preview

Sequencer’s Lock Viewport to Camera Cuts button (the padlock at the top right of the Sequencer toolbar) changes how you preview the sequence. With it enabled, the viewport renders whatever the Camera Cuts track says. Without it, the viewport renders its own camera and you will not see any cutting issues — everything looks fine because nothing is cutting. Always preview with the lock enabled before rendering a movie.

Also watch for the Keep Original Viewport Camera option under Sequencer preferences. If enabled, the viewport resumes the editor camera after a cut ends, which is harmless during editing but does not represent what a packaged build will show.

“Every cut needs a transform at the exact frame. If you can’t see a keyframe dot on the Transform track where the cut line is, that is your bug.”

Related Issues

If your sequence animation plays in the editor but not at runtime, see Sequencer Animation Not Playing at Runtime. If the camera animation plays correctly but cloth or hair on the character snaps to the wrong location at cut boundaries, check Motion Warping Not Aligning — the same teleport-reset logic applies.

No transform keyframe at the cut = one frame of the camera’s default pose. Every. Single. Time.