Domain: Humanities and Social Sciences — Linguistics
Target concept: Windscreen used to reduce microphone movement caused by wind during outdoor use

Video generation prompt: Outdoors in a gentle breeze, with a wind indicator such as nearby grass or a hanging fabric ribbon visibly swaying to mark the wind, two identically configured microphones are mounted side by side and face the same direction as gusts pass through: one microphone is left fully exposed, the other is enclosed in a thick foam windscreen. Each microphone feeds its own visible audio level meter (an analog VU needle or digital waveform display) placed in frame beside its stand, showing the incoming signal in real time.

Evaluation guide:
(i) Target concept: Aerodynamic damping of airborne pressure fluctuations via porous medium.
Minimum mechanism: Wind must generate measurable air velocity gradients across microphone grilles; foam must be sufficiently thick and porous to decouple incident turbulence from diaphragm motion; exposed microphone must lack any flow-diffusing barrier.
(ii)Storyline: [Frame 0–2] Static baseline: microphones fixed, wind indicator motionless, both grilles still. → [Frame 3–5] Wind onset: wind indicator begins directional motion (e.g., grass leans left), exposed grille initiates high-frequency vibration, windscreen foam begins surface micro-jiggle. → [Frame 6–8] Peak gust: wind indicator motion intensifies uniformly, exposed grille shows visible concave/convex deformation, windscreen-enclosed grille remains geometrically stable, foam exhibits full compression-release cycle. → [Frame 9–10] Gust decay: wind indicator motion attenuates smoothly, exposed grille vibration damps rapidly, foam returns to neutral volume; all elements maintain fixed spatial relationships and optical continuity. Perspective: fixed frontal view, eye-level, shallow depth of field focusing on grille plane; no obstructions; full visibility of both grilles and foam envelope.

Manual:
Experimental Procedure
1. Mount two identical microphones side-by-side on fixed stands outdoors.
2. Leave left microphone fully exposed; fit right microphone with thick, opaque foam windscreen covering entire grille.
3. Orient both microphones identically, facing into gentle breeze.
4. Record 10 seconds as wind gusts pass through scene.
Observation of Experimental Phenomena
Exposed microphone grille visibly vibrates/distorts during wind; windscreen-enclosed microphone grille remains still and undistorted; foam surface shows subtle compression-release motion; background wind indicators (e.g., grass, leaves) move synchronously.
Summary of Experimental Principles
Foam windscreens reduce wind-induced microphone diaphragm movement by dissipating turbulent airflow energy via viscous drag and flow diffusion across porous structure — preventing low-frequency rumble and handling noise.

Prompt Grounding rubric:
level_1: No microphones visible; or only one microphone present; or windscreen absent from both microphones; or microphones not mounted side-by-side; or no outdoor setting (e.g., indoor, studio, black background); or no visible wind effect (e.g., no moving foliage, no fabric flutter, no hair movement, no dust motion)
level_2: Two microphones present and side-by-side, but at least one of the following is missing: (a) one microphone has a thick foam windscreen visibly enclosing its grille, (b) the other microphone is fully exposed with no windscreen, (c) both microphones face same direction, (d) outdoor setting with at least one visual wind indicator (e.g., swaying grass, fluttering cloth, moving leaves)
level_3: Two identically shaped and sized microphones mounted rigidly side-by-side in outdoor setting; one microphone fully exposed (no covering on grille); the other microphone completely enclosed by a thick, opaque foam windscreen covering entire grille area; both microphones oriented identically (grilles parallel, facing same direction); at least one unambiguous wind indicator present and active (e.g., continuous leaf motion, fabric ripple, or hair displacement)
level_4: All conditions for score 3 met, AND wind indicator shows synchronous, continuous motion across the frame (no isolated or delayed motion), AND spatial relationship preserved throughout: microphones remain fixed in position relative to each other and to background; AND windscreen appears voluminous and texturally distinct (matte, porous, non-reflective foam), not thin mesh, fabric, or fur
level_5: All conditions for score 4 met, AND exposed microphone grille is fully visible and unobstructed (no partial occlusion by windscreen, hand, or debris), AND windscreen completely envelops the microphone body up to but not beyond the base of the grille (no overhang covering mic body or stand), AND both microphones share identical mounting hardware (same clip, same stand height, same angle), AND wind indicator motion is globally consistent (e.g., all grass blades sway left-to-right together, no contradictory local motion)

Scientific and Causal Correctness rubric:
level_1: No causal contrast shown; e.g., both microphones appear identical in behavior; or windscreen is shown on both or neither; or wind indicator is static while wind is claimed; or exposed microphone shows no physical response to wind while wind indicator moves
level_2: Wind indicator moves, but microphones show no differential response: both exhibit identical vibration, grille distortion, or cable shake; or windscreen appears rigid and immobile while exposed microphone vibrates, violating foam’s damping function; or windscreen is translucent/transparent and fails to obscure grille texture
level_3: Exposed microphone grille visibly vibrates or distorts during wind indicator motion; windscreen-enclosed microphone grille shows no visible vibration or distortion; windscreen maintains structural integrity (no collapse, flapping, or detachment) while wind indicator is active
level_4: All conditions for score 3 met, AND windscreen surface exhibits fine-textured, high-amplitude micro-motion (subtle jiggling or compression-release) synchronized with wind indicator pulses, confirming dynamic energy absorption; AND exposed microphone grille shows sharp, high-frequency oscillation (visible edge blur or rapid shimmer) absent in windscreen-enclosed unit
level_5: All conditions for score 4 met, AND no spurious motion appears on windscreen-enclosed microphone beyond its foam surface (e.g., zero grille shimmer, zero stand wobble, zero cable sway), AND exposed microphone shows unambiguous, localized grille deformation (concave/convex bending) coinciding temporally with peak wind indicator motion, confirming direct aerodynamic loading

Spatiotemporal Consistency rubric:
level_1: A severe break in continuity: a microphone or its stand teleports or vanishes between frames, the wind indicator appears or disappears abruptly, lighting jumps discontinuously (e.g., full sun to deep shadow within a single frame) with no transition, the camera cuts or spins with no motion blur, or a level meter appears or disappears without a hand visibly placing or removing it.
level_2: A moderate break: the two microphones visibly shift apart or together with no hand moving them, the wind indicator's motion starts or stops abruptly with no ramp-up or ramp-down, the foam windscreen changes size or shape mid-clip (e.g., swells then shrinks) with no gust to explain it, or the camera drifts sideways while background objects fail to shift with matching parallax.
level_3: A minor but noticeable inconsistency: the microphones' alignment wavers slightly from frame to frame (the grille centers drift by roughly 10% or less of their spacing) without ever fully separating; the wind indicator briefly freezes for a moment then resumes the same direction and speed; the foam windscreen shows a brief, unnatural glint inconsistent with a matte surface but never changes shape.
level_4: Beyond level 3's minor allowances: no frame shows the two microphone grille planes out of alignment with each other, the wind indicator's motion runs continuously in one consistent direction without reversing or freezing, and the foam windscreen's size and matte appearance stay constant throughout with no flattening, stretching, or turning see-through.
level_5: Beyond level 4: the whole clip reads as one continuous take; the wind indicator's swaying and any small meter-needle movement are smooth with no visible strobing or juddering, motion blur is proportional to speed (blurred on the moving wind indicator and, during gusts, on the exposed microphone's wind-vibrating grille; sharp on the windscreen-enclosed microphone, both stands, and the rest of each microphone body), and depth ordering stays correct throughout, with nearer objects such as foreground grass consistently occluding the microphones behind them and nothing appearing to float free of the ground or the stand it is attached to.