From 1e6be1295d9c87f73141b3de190973c14f1bf762 Mon Sep 17 00:00:00 2001
From: young <young@youngs-MacBook-Air.local>
Date: Mon, 31 Aug 2026 13:17:55 +1000
Subject: [PATCH] Make motion blur streakier and simplify its controls

---
 src/components/video-editor/SettingsPanel.tsx | 148 ------------------
 src/components/video-editor/VideoEditor.tsx   |  12 --
 src/components/video-editor/audio.test.ts     |   4 +-
 .../video-editor/cursorMotionPresets.ts       |  10 +-
 .../video-editor/projectPersistence.ts        |   6 +-
 .../videoPlayback/cursorRenderer.ts           |   2 +-
 .../videoPlayback/zoomTransform.test.ts       |  45 +++++-
 .../videoPlayback/zoomTransform.ts            |  29 ++--
 8 files changed, 69 insertions(+), 187 deletions(-)

diff --git a/src/components/video-editor/SettingsPanel.tsx b/src/components/video-editor/SettingsPanel.tsx
index 81c934d5..5146aa1d 100644
--- a/src/components/video-editor/SettingsPanel.tsx
+++ b/src/components/video-editor/SettingsPanel.tsx
@@ -22,10 +22,6 @@ import { Switch } from "@/components/ui/switch";
 import { ToggleGroup, ToggleGroupItem } from "@/components/ui/toggle-group";
 import { useTheme } from "@/contexts/ThemeContext";
 import { getAssetPath, getRenderableVideoUrl, getWallpaperThumbnailUrl } from "@/lib/assetPath";
-import {
-	TEMPORAL_MOTION_BLUR_DEFAULT_SAMPLE_COUNT,
-	TEMPORAL_MOTION_BLUR_DEFAULT_SHUTTER_FRACTION,
-} from "@/lib/exporter/temporalMotionBlur";
 import { cn } from "@/lib/utils";
 import type { BuiltInWallpaper } from "@/lib/wallpapers";
 import {
@@ -64,7 +60,6 @@ import type {
 	WebcamPositionPreset,
 	ZoomDepth,
 	ZoomMode,
-	ZoomMotionBlurTuning,
 	ZoomTransitionEasing,
 } from "./types";
 import {
@@ -78,7 +73,6 @@ import {
 	DEFAULT_CURSOR_CLICK_EFFECT_DURATION_MS,
 	DEFAULT_CURSOR_CLICK_EFFECT_OPACITY,
 	DEFAULT_CURSOR_CLICK_EFFECT_SCALE,
-	DEFAULT_CURSOR_MOTION_BLUR,
 	DEFAULT_CURSOR_SIZE,
 	DEFAULT_CURSOR_STYLE,
 	DEFAULT_CURSOR_SWAY,
@@ -92,7 +86,6 @@ import {
 	DEFAULT_WEBCAM_SHADOW,
 	DEFAULT_WEBCAM_SIZE,
 	DEFAULT_ZOOM_IN_DURATION_MS,
-	DEFAULT_ZOOM_MOTION_BLUR_TUNING,
 	DEFAULT_ZOOM_OUT_DURATION_MS,
 } from "./types";
 import { fromCursorSwaySliderValue, toCursorSwaySliderValue } from "./videoPlayback/cursorSway";
@@ -548,14 +541,6 @@ interface SettingsPanelProps {
 	onShadowChange?: (intensity: number) => void;
 	backgroundBlur?: number;
 	onBackgroundBlurChange?: (amount: number) => void;
-	zoomMotionBlurTuning?: ZoomMotionBlurTuning;
-	onZoomMotionBlurTuningChange?: (tuning: ZoomMotionBlurTuning) => void;
-	zoomTemporalMotionBlur?: number;
-	onZoomTemporalMotionBlurChange?: (amount: number) => void;
-	zoomMotionBlurSampleCount?: number | null;
-	onZoomMotionBlurSampleCountChange?: (count: number | null) => void;
-	zoomMotionBlurShutterFraction?: number | null;
-	onZoomMotionBlurShutterFractionChange?: (fraction: number | null) => void;
 	connectZooms?: boolean;
 	onConnectZoomsChange?: (enabled: boolean) => void;
 	autoApplyFreshRecordingAutoZooms?: boolean;
@@ -600,8 +585,6 @@ interface SettingsPanelProps {
 	onCameraSpringMassMultiplierChange?: (multiplier: number) => void;
 	zoomClassicMode?: boolean;
 	onZoomClassicModeChange?: (enabled: boolean) => void;
-	cursorMotionBlur?: number;
-	onCursorMotionBlurChange?: (amount: number) => void;
 	cursorClickEffect?: CursorClickEffectStyle;
 	onCursorClickEffectChange?: (effect: CursorClickEffectStyle) => void;
 	cursorClickEffectColor?: string;
@@ -1009,8 +992,6 @@ export function SettingsPanel({
 	onShadowChange,
 	backgroundBlur = 0,
 	onBackgroundBlurChange,
-	zoomMotionBlurTuning = DEFAULT_ZOOM_MOTION_BLUR_TUNING,
-	onZoomMotionBlurTuningChange,
 	connectZooms = true,
 	onConnectZoomsChange,
 	autoApplyFreshRecordingAutoZooms = true,
@@ -1043,8 +1024,6 @@ export function SettingsPanel({
 	onCameraSpringMassMultiplierChange,
 	zoomClassicMode = false,
 	onZoomClassicModeChange,
-	cursorMotionBlur = DEFAULT_CURSOR_MOTION_BLUR,
-	onCursorMotionBlurChange,
 	cursorClickEffect = DEFAULT_CURSOR_CLICK_EFFECT,
 	onCursorClickEffectChange,
 	cursorClickEffectColor = DEFAULT_CURSOR_CLICK_EFFECT_COLOR,
@@ -1546,7 +1525,6 @@ export function SettingsPanel({
 	};
 
 	const resetZoomSection = () => {
-		onZoomMotionBlurTuningChange?.(initialEditorPreferences.zoomMotionBlurTuning);
 		onCameraSpringStiffnessMultiplierChange?.(
 			initialEditorPreferences.cameraSpringStiffnessMultiplier,
 		);
@@ -1572,7 +1550,6 @@ export function SettingsPanel({
 			initialEditorPreferences.cursorSpringDampingMultiplier,
 		);
 		onCursorSpringMassMultiplierChange?.(initialEditorPreferences.cursorSpringMassMultiplier);
-		onCursorMotionBlurChange?.(initialEditorPreferences.cursorMotionBlur);
 		onCursorClickEffectChange?.(initialEditorPreferences.cursorClickEffect);
 		onCursorClickEffectColorChange?.(initialEditorPreferences.cursorClickEffectColor);
 		onCursorClickEffectScaleChange?.(initialEditorPreferences.cursorClickEffectScale);
@@ -1593,7 +1570,6 @@ export function SettingsPanel({
 				cursorSpringStiffnessMultiplier,
 				cursorSpringDampingMultiplier,
 				cursorSpringMassMultiplier,
-				cursorMotionBlur,
 				cursorClickBounce,
 				cursorClickBounceDuration,
 			}) ?? "focused"
@@ -1601,7 +1577,6 @@ export function SettingsPanel({
 	}, [
 		cursorClickBounce,
 		cursorClickBounceDuration,
-		cursorMotionBlur,
 		cursorSize,
 		cursorSmoothing,
 		cursorSpringDampingMultiplier,
@@ -1620,7 +1595,6 @@ export function SettingsPanel({
 		onCursorSpringStiffnessMultiplierChange?.(preset.cursorSpringStiffnessMultiplier);
 		onCursorSpringDampingMultiplierChange?.(preset.cursorSpringDampingMultiplier);
 		onCursorSpringMassMultiplierChange?.(preset.cursorSpringMassMultiplier);
-		onCursorMotionBlurChange?.(preset.cursorMotionBlur);
 		onCursorClickBounceChange?.(preset.cursorClickBounce);
 		onCursorClickBounceDurationChange?.(preset.cursorClickBounceDuration);
 	};
@@ -2719,104 +2693,6 @@ export function SettingsPanel({
 							</div>
 						</div>
 
-						<div className="space-y-1.5 rounded-lg border border-foreground/10 bg-background/60 px-3 py-3">
-							<div>
-								<div className="text-[11px] font-medium text-foreground">
-									{tSettings("effects.motionBlurDebug", "Motion Blur Debug")}
-								</div>
-								<div className="mt-0.5 text-[10px] text-muted-foreground">
-									{tSettings(
-										"effects.motionBlurDebugHint",
-										"Development-only tuning for the split move-vs-zoom blur path. Pan controls drive the streak filter, and zoom controls drive the focus-centered zoom filter.",
-									)}
-								</div>
-							</div>
-							<SliderControl
-								label={tSettings("effects.motionBlurPanThreshold", "Pan threshold")}
-								value={zoomMotionBlurTuning.panVelocityThreshold}
-								defaultValue={
-									initialEditorPreferences.zoomMotionBlurTuning
-										.panVelocityThreshold
-								}
-								min={0}
-								max={240}
-								step={1}
-								onChange={(value) =>
-									onZoomMotionBlurTuningChange?.({
-										...zoomMotionBlurTuning,
-										panVelocityThreshold: value,
-									})
-								}
-								formatValue={(value) => `${Math.round(value)} px/s`}
-								parseInput={(text) =>
-									parseFloat(text.replace(/px\/s$/i, "").trim())
-								}
-							/>
-							<SliderControl
-								label={tSettings("effects.motionBlurPanStrength", "Pan max blur")}
-								value={zoomMotionBlurTuning.maxDirectionalBlurPx}
-								defaultValue={
-									initialEditorPreferences.zoomMotionBlurTuning
-										.maxDirectionalBlurPx
-								}
-								min={0}
-								max={96}
-								step={0.1}
-								onChange={(value) =>
-									onZoomMotionBlurTuningChange?.({
-										...zoomMotionBlurTuning,
-										maxDirectionalBlurPx: value,
-									})
-								}
-								formatValue={(value) => `${value.toFixed(1)} px`}
-								parseInput={(text) => parseFloat(text.replace(/px$/i, "").trim())}
-							/>
-							<SliderControl
-								label={tSettings(
-									"effects.motionBlurZoomThreshold",
-									"Zoom threshold",
-								)}
-								value={zoomMotionBlurTuning.zoomVelocityThreshold}
-								defaultValue={
-									initialEditorPreferences.zoomMotionBlurTuning
-										.zoomVelocityThreshold
-								}
-								min={0}
-								max={0.4}
-								step={0.005}
-								onChange={(value) =>
-									onZoomMotionBlurTuningChange?.({
-										...zoomMotionBlurTuning,
-										zoomVelocityThreshold: value,
-									})
-								}
-								formatValue={(value) => value.toFixed(3)}
-								parseInput={(text) => parseFloat(text)}
-							/>
-							<SliderControl
-								label={tSettings(
-									"effects.motionBlurZoomStrength",
-									"Zoom blur strength",
-								)}
-								value={zoomMotionBlurTuning.maxRadialBlurStrength}
-								defaultValue={
-									initialEditorPreferences.zoomMotionBlurTuning
-										.maxRadialBlurStrength
-								}
-								min={0}
-								max={1.5}
-								step={0.005}
-								onChange={(value) =>
-									onZoomMotionBlurTuningChange?.({
-										...zoomMotionBlurTuning,
-										maxRadialBlurStrength: value,
-									})
-								}
-								formatValue={(value) => value.toFixed(3)}
-								parseInput={(text) => parseFloat(text)}
-							/>
-						</div>
-
 						<div className="space-y-1.5 rounded-lg border border-foreground/10 bg-background/60 px-3 py-3">
 							<div>
 								<div className="text-[11px] font-medium text-foreground">
@@ -3061,19 +2937,6 @@ export function SettingsPanel({
 						)}
 					</div>
 				)}
-				{showDevMotionControls ? (
-					<div className="rounded-lg border border-foreground/10 bg-foreground/[0.03] px-3 py-2">
-						<div className="text-[10px] text-muted-foreground">
-							{tSettings(
-								"effects.exportBlurMovedToDev",
-								"Export blur tuning is available in Settings > Dev.",
-							)}
-						</div>
-						<div className="mt-1 text-[12px] font-medium text-foreground">
-							{`${TEMPORAL_MOTION_BLUR_DEFAULT_SAMPLE_COUNT} samples · ${Math.round(TEMPORAL_MOTION_BLUR_DEFAULT_SHUTTER_FRACTION * 100)}% shutter`}
-						</div>
-					</div>
-				) : null}
 				{selectedZoomId && (
 					<Button
 						onClick={() => {
@@ -3412,17 +3275,6 @@ export function SettingsPanel({
 								formatValue={(v) => `${v.toFixed(2)}×`}
 								parseInput={(text) => parseFloat(text.replace(/×$/, ""))}
 							/>
-							<SliderControl
-								label={tSettings("effects.cursorMotionBlur")}
-								value={cursorMotionBlur}
-								defaultValue={DEFAULT_CURSOR_MOTION_BLUR}
-								min={0}
-								max={2}
-								step={0.05}
-								onChange={(v) => onCursorMotionBlurChange?.(v)}
-								formatValue={(v) => `${v.toFixed(2)}×`}
-								parseInput={(text) => parseFloat(text.replace(/×$/, ""))}
-							/>
 							<CursorClickEffectCards
 								title={tSettings(
 									"effects.cursorClickEffects.title",
diff --git a/src/components/video-editor/VideoEditor.tsx b/src/components/video-editor/VideoEditor.tsx
index ad38cb4a..f8e0dea5 100644
--- a/src/components/video-editor/VideoEditor.tsx
+++ b/src/components/video-editor/VideoEditor.tsx
@@ -6372,16 +6372,6 @@ export default function VideoEditor() {
 								onShadowChange={setShadowIntensity}
 								backgroundBlur={backgroundBlur}
 								onBackgroundBlurChange={setBackgroundBlur}
-								zoomMotionBlurTuning={zoomMotionBlurTuning}
-								onZoomMotionBlurTuningChange={setZoomMotionBlurTuning}
-								zoomTemporalMotionBlur={zoomTemporalMotionBlur}
-								onZoomTemporalMotionBlurChange={setZoomTemporalMotionBlur}
-								zoomMotionBlurSampleCount={zoomMotionBlurSampleCount}
-								onZoomMotionBlurSampleCountChange={setZoomMotionBlurSampleCount}
-								zoomMotionBlurShutterFraction={zoomMotionBlurShutterFraction}
-								onZoomMotionBlurShutterFractionChange={
-									setZoomMotionBlurShutterFraction
-								}
 								autoApplyFreshRecordingAutoZooms={autoApplyFreshRecordingAutoZooms}
 								onAutoApplyFreshRecordingAutoZoomsChange={
 									setAutoApplyFreshRecordingAutoZooms
@@ -6436,8 +6426,6 @@ export default function VideoEditor() {
 								onCameraSpringMassMultiplierChange={setCameraSpringMassMultiplier}
 								zoomClassicMode={zoomClassicMode}
 								onZoomClassicModeChange={setZoomClassicMode}
-								cursorMotionBlur={cursorMotionBlur}
-								onCursorMotionBlurChange={setCursorMotionBlur}
 								cursorClickEffect={cursorClickEffect}
 								cursorClickEffectColor={cursorClickEffectColor}
 								onCursorClickEffectChange={setCursorClickEffect}
diff --git a/src/components/video-editor/audio.test.ts b/src/components/video-editor/audio.test.ts
index bd138d00..86ec67aa 100644
--- a/src/components/video-editor/audio.test.ts
+++ b/src/components/video-editor/audio.test.ts
@@ -1,6 +1,7 @@
 import * as fc from "fast-check";
 import { describe, expect, it } from "vitest";
 import { CURSOR_MOTION_PRESETS } from "./cursorMotionPresets";
+import { DEFAULT_CURSOR_MOTION_BLUR } from "./types";
 import {
 	fromFileUrl,
 	normalizeProjectEditor,
@@ -253,7 +254,6 @@ describe("Motion preset normalization", () => {
 			cursorSpringStiffnessMultiplier: smooth.cursorSpringStiffnessMultiplier,
 			cursorSpringDampingMultiplier: smooth.cursorSpringDampingMultiplier,
 			cursorSpringMassMultiplier: smooth.cursorSpringMassMultiplier,
-			cursorMotionBlur: smooth.cursorMotionBlur,
 			cursorClickBounce: smooth.cursorClickBounce,
 			cursorClickBounceDuration: smooth.cursorClickBounceDuration,
 		} as any);
@@ -288,7 +288,7 @@ describe("Motion preset normalization", () => {
 		);
 		expect(result.cursorSpringDampingMultiplier).toBe(focused.cursorSpringDampingMultiplier);
 		expect(result.cursorSpringMassMultiplier).toBe(focused.cursorSpringMassMultiplier);
-		expect(result.cursorMotionBlur).toBe(focused.cursorMotionBlur);
+		expect(result.cursorMotionBlur).toBe(DEFAULT_CURSOR_MOTION_BLUR);
 		expect(result.cursorClickBounce).toBe(focused.cursorClickBounce);
 		expect(result.cursorClickBounceDuration).toBe(focused.cursorClickBounceDuration);
 	});
diff --git a/src/components/video-editor/cursorMotionPresets.ts b/src/components/video-editor/cursorMotionPresets.ts
index 04e9745d..22f2dc67 100644
--- a/src/components/video-editor/cursorMotionPresets.ts
+++ b/src/components/video-editor/cursorMotionPresets.ts
@@ -1,8 +1,4 @@
-import {
-	DEFAULT_CURSOR_MOTION_BLUR,
-	DEFAULT_ZOOM_IN_DURATION_MS,
-	DEFAULT_ZOOM_OUT_DURATION_MS,
-} from "./types";
+import { DEFAULT_ZOOM_IN_DURATION_MS, DEFAULT_ZOOM_OUT_DURATION_MS } from "./types";
 
 export type CursorMotionPresetId = "focused" | "smooth";
 
@@ -17,7 +13,6 @@ export interface CursorMotionPreset {
 	cursorSpringStiffnessMultiplier: number;
 	cursorSpringDampingMultiplier: number;
 	cursorSpringMassMultiplier: number;
-	cursorMotionBlur: number;
 	cursorClickBounce: number;
 	cursorClickBounceDuration: number;
 }
@@ -30,7 +25,6 @@ export interface CursorMotionPresetSelectionInput {
 	cursorSpringStiffnessMultiplier: number;
 	cursorSpringDampingMultiplier: number;
 	cursorSpringMassMultiplier: number;
-	cursorMotionBlur: number;
 	cursorClickBounce: number;
 	cursorClickBounceDuration: number;
 }
@@ -39,7 +33,6 @@ const SHARED_CURSOR_PRESET_VALUES = {
 	cursorSize: 2.5,
 	cursorSmoothing: 0.67,
 	cursorSpringMassMultiplier: 1.29,
-	cursorMotionBlur: DEFAULT_CURSOR_MOTION_BLUR,
 	cursorClickBounce: 3.5,
 	cursorClickBounceDuration: 350,
 } as const;
@@ -80,7 +73,6 @@ export function getMatchingCursorMotionPresetId(
 			preset.cursorSpringStiffnessMultiplier === values.cursorSpringStiffnessMultiplier &&
 			preset.cursorSpringDampingMultiplier === values.cursorSpringDampingMultiplier &&
 			preset.cursorSpringMassMultiplier === values.cursorSpringMassMultiplier &&
-			preset.cursorMotionBlur === values.cursorMotionBlur &&
 			preset.cursorClickBounce === values.cursorClickBounce &&
 			preset.cursorClickBounceDuration === values.cursorClickBounceDuration
 		) {
diff --git a/src/components/video-editor/projectPersistence.ts b/src/components/video-editor/projectPersistence.ts
index 93c0c5a1..93292297 100644
--- a/src/components/video-editor/projectPersistence.ts
+++ b/src/components/video-editor/projectPersistence.ts
@@ -46,6 +46,7 @@ import {
 	DEFAULT_CURSOR_CLICK_EFFECT_DURATION_MS,
 	DEFAULT_CURSOR_CLICK_EFFECT_OPACITY,
 	DEFAULT_CURSOR_CLICK_EFFECT_SCALE,
+	DEFAULT_CURSOR_MOTION_BLUR,
 	DEFAULT_CURSOR_STYLE,
 	DEFAULT_CURSOR_SWAY,
 	DEFAULT_FIGURE_DATA,
@@ -851,9 +852,6 @@ export function normalizeProjectEditor(editor: Partial<ProjectEditorState>): Pro
 		cursorSpringMassMultiplier: isFiniteNumber(editor.cursorSpringMassMultiplier)
 			? clamp(editor.cursorSpringMassMultiplier, 0.25, 3)
 			: DEFAULT_MOTION_PRESET.cursorSpringMassMultiplier,
-		cursorMotionBlur: isFiniteNumber((editor as Partial<ProjectEditorState>).cursorMotionBlur)
-			? clamp((editor as Partial<ProjectEditorState>).cursorMotionBlur as number, 0, 2)
-			: DEFAULT_MOTION_PRESET.cursorMotionBlur,
 		cursorClickBounce: isFiniteNumber((editor as Partial<ProjectEditorState>).cursorClickBounce)
 			? clamp((editor as Partial<ProjectEditorState>).cursorClickBounce as number, 0, 5)
 			: DEFAULT_MOTION_PRESET.cursorClickBounce,
@@ -942,7 +940,7 @@ export function normalizeProjectEditor(editor: Partial<ProjectEditorState>): Pro
 		zoomSmoothness: DEFAULT_ZOOM_SMOOTHNESS,
 		zoomClassicMode:
 			typeof editor.zoomClassicMode === "boolean" ? editor.zoomClassicMode : false,
-		cursorMotionBlur: normalizedMotionPreset.cursorMotionBlur,
+		cursorMotionBlur: DEFAULT_CURSOR_MOTION_BLUR,
 		cursorClickBounce: normalizedMotionPreset.cursorClickBounce,
 		cursorClickBounceDuration: normalizedMotionPreset.cursorClickBounceDuration,
 		cursorSway: isFiniteNumber((editor as Partial<ProjectEditorState>).cursorSway)
diff --git a/src/components/video-editor/videoPlayback/cursorRenderer.ts b/src/components/video-editor/videoPlayback/cursorRenderer.ts
index 16538285..def88661 100644
--- a/src/components/video-editor/videoPlayback/cursorRenderer.ts
+++ b/src/components/video-editor/videoPlayback/cursorRenderer.ts
@@ -114,7 +114,7 @@ export interface CursorRenderConfig {
 const MIN_CURSOR_VIEWPORT_SCALE = 0;
 // Keep the cursor visually responsive while sharing the camera's frame-rate
 // normalization, kernel, and directional offset formula.
-const CURSOR_DIRECTIONAL_BLUR_STRENGTH = 3.2;
+const CURSOR_DIRECTIONAL_BLUR_STRENGTH = 2;
 const CURSOR_TIME_DISCONTINUITY_MS = 100;
 const CURSOR_SWAY_SMOOTHING_MULTIPLIER = 0.7;
 const CURSOR_SWAY_SMOOTHING_OFFSET = 0.18;
diff --git a/src/components/video-editor/videoPlayback/zoomTransform.test.ts b/src/components/video-editor/videoPlayback/zoomTransform.test.ts
index faf5f6e1..79333ec9 100644
--- a/src/components/video-editor/videoPlayback/zoomTransform.test.ts
+++ b/src/components/video-editor/videoPlayback/zoomTransform.test.ts
@@ -132,10 +132,53 @@ describe("applyZoomTransform motion blur routing", () => {
 			frameTimeMs: 1016,
 		});
 
-		expect(Math.abs(zoomBlurFilter.strength)).toBeGreaterThan(0);
+		expect(zoomBlurFilter.strength).toBeGreaterThan(0);
 		expect(Math.hypot(motionBlurFilter.velocity.x, motionBlurFilter.velocity.y)).toBe(0);
 		expect(zoomBlurFilter.center.x).toBeCloseTo(stageSize.width / 2, 0);
 		expect(zoomBlurFilter.center.y).toBeCloseTo(stageSize.height / 2, 0);
 		expect(zoomBlurFilter.radius).toBe(-1);
 	});
+
+	it("keeps a zoom on the radial path even when its center moves farther than its size", () => {
+		const motionBlurState = createMotionBlurState();
+		const motionBlurFilter = {
+			velocity: { x: 0, y: 0 },
+			kernelSize: 5,
+			offset: 0,
+		};
+		const zoomBlurFilter = {
+			strength: 0,
+			center: { x: 0, y: 0 },
+			innerRadius: 0,
+			radius: -1,
+		};
+		const sharedParams = {
+			cameraContainer: createStubContainer() as never,
+			zoomBlurFilter: zoomBlurFilter as never,
+			motionBlurFilter: motionBlurFilter as never,
+			stageSize: { width: 1280, height: 720 },
+			baseMask: { x: 80, y: 60, width: 1120, height: 600 },
+			zoomScale: 1,
+			focusX: 0.5,
+			focusY: 0.5,
+			isPlaying: true,
+			motionBlurAmount: 1,
+			motionBlurState,
+		};
+
+		applyZoomTransform({
+			...sharedParams,
+			transformOverride: { scale: 1, x: 0, y: 0 },
+			frameTimeMs: 1000,
+		});
+		applyZoomTransform({
+			...sharedParams,
+			transformOverride: { scale: 1.01, x: 120, y: 0 },
+			frameTimeMs: 1016,
+		});
+
+		expect(zoomBlurFilter.strength).toBeGreaterThan(0);
+		expect(Math.hypot(motionBlurFilter.velocity.x, motionBlurFilter.velocity.y)).toBe(0);
+		expect(zoomBlurFilter.innerRadius).toBe(0);
+	});
 });
diff --git a/src/components/video-editor/videoPlayback/zoomTransform.ts b/src/components/video-editor/videoPlayback/zoomTransform.ts
index 26ff84a5..55ace06a 100644
--- a/src/components/video-editor/videoPlayback/zoomTransform.ts
+++ b/src/components/video-editor/videoPlayback/zoomTransform.ts
@@ -6,6 +6,10 @@ import { DEFAULT_ZOOM_MOTION_BLUR_TUNING, type ZoomMotionBlurTuning } from "../t
 const MIN_DIRECTIONAL_BLUR_MAGNITUDE = 0.01;
 const DIRECTIONAL_BLUR_KERNEL_SIZE = 13;
 const DIRECTIONAL_BLUR_OFFSET_DIVISOR = 32;
+const SPATIAL_PAN_SHUTTER_MULTIPLIER = 4;
+// Spatial equivalent of a longer exposure. This extends the one-pass zoom
+// trail without multiplying scene renders like temporal accumulation does.
+const SPATIAL_ZOOM_SHUTTER_MULTIPLIER = 4;
 
 export interface DirectionalMotionBlur {
 	velocity: { x: number; y: number };
@@ -285,6 +289,7 @@ function resolveZoomBlurStrength(
 	return (
 		motionBlurAmount *
 		fpsScale *
+		SPATIAL_ZOOM_SHUTTER_MULTIPLIER *
 		(motionBlurTuning.maxRadialBlurStrength /
 			DEFAULT_ZOOM_MOTION_BLUR_TUNING.maxRadialBlurStrength)
 	);
@@ -305,6 +310,9 @@ function computeSizeDelta(previousQuad: TransformQuad, currentQuad: TransformQua
 }
 
 function computeZoomStrength(previousQuad: TransformQuad, currentQuad: TransformQuad) {
+	// Keep the spatial approximation sampling inward. Sampling outward during
+	// expansion can leave the filter's captured texture and produce transparent
+	// or black frames; true directionality requires temporal/overscanned input.
 	return Math.abs(1 - currentQuad.diagonal / Math.max(0.0001, previousQuad.diagonal));
 }
 
@@ -325,22 +333,22 @@ function classifyMotionMode(
 				Math.max(0.0001, currentQuad.diagonal) / Math.max(0.0001, previousQuad.diagonal),
 			),
 		) / Math.max(0.0001, deltaSeconds);
-	const moveActive = moveVelocity >= motionBlurTuning.panVelocityThreshold;
-	const zoomActive = zoomVelocity >= motionBlurTuning.zoomVelocityThreshold;
+	const moveActive = moveDistance > 0.001 && moveVelocity > motionBlurTuning.panVelocityThreshold;
+	const zoomActive =
+		zoomDistance > 0.001 && zoomVelocity > motionBlurTuning.zoomVelocityThreshold;
 
 	if (!moveActive && !zoomActive) {
 		return null;
 	}
 
-	if (moveActive && !zoomActive) {
-		return "move";
-	}
-
-	if (zoomActive && !moveActive) {
+	// Any meaningful scale change is a zoom. The inferred zoom center already
+	// accounts for the translation caused by an off-center zoom, so routing it
+	// through pan blur would turn a straight radial zoom into a directional smear.
+	if (zoomActive) {
 		return "zoom";
 	}
 
-	return zoomDistance > moveDistance ? "zoom" : "move";
+	return "move";
 }
 
 function createZeroPoint(): Point2D {
@@ -373,8 +381,9 @@ function analyzeCameraStep({
 		moveDelta,
 		motionBlurAmount,
 		deltaSeconds,
-		motionBlurTuning.maxDirectionalBlurPx /
-			DEFAULT_ZOOM_MOTION_BLUR_TUNING.maxDirectionalBlurPx,
+		SPATIAL_PAN_SHUTTER_MULTIPLIER *
+			(motionBlurTuning.maxDirectionalBlurPx /
+				DEFAULT_ZOOM_MOTION_BLUR_TUNING.maxDirectionalBlurPx),
 	);
 
 	return {