Motion Blur / Panning Shutter Speed Estimator implementation

Binding contract

This record describes what an executable surface must bind and validate. It does not claim that a public calculator, package, or production route is deployed.

Record owner

Guth Instruments

Lifecycle

verified-with-binding-errata

Evidence ID

t5-097

Effect

Computation or source lookup only

Input and validation requirements

The specification's formula requires pixel pitch, but pixel pitch is absent from the listed inputs. It also promises a shutter-speed range without defining range bounds or any formula branches. Zero distance and zero desired blur additionally produce undefined or non-finite shutter-speed results that require validation handling.

Required corrections

[
  {
    "vector": 1,
    "field": "maximum_shutter_time_s / hz",
    "wrong": "0.0025 / 400",
    "correct": "0.00025 / 4000",
    "cause": "10× slip; her own v2/v4 use the same formula correctly"
  }
]

Inspectable interface fixture

The sample below is evidence for interface and validation tests, not a production implementation.

{
  "inputs": {
    "subject_speed_m_per_s": 10,
    "distance_m": 50,
    "focal_length_m": 0.2,
    "pixel_pitch_m": 0.000005,
    "desired_blur_px": 2
  },
  "expected_outputs": {
    "maximum_shutter_time_s": 0.0025,
    "equivalent_shutter_speed_hz": 400
  },
  "working": "angularVelocity = 10 / 50 = 0.2 rad/s.\\nshutterTime = desiredBlur × pixelPitch / (angularVelocity × focalLength)\\n= 2 × 0.000005 / (0.2 × 0.2)\\n= 0.000010 / 0.04\\n= 0.0025 s.\\nEquivalent shutter rate = 1 / 0.0025 = 400 Hz, conventionally 1/400 s."
}

Other records

Sources and evidence

These pointers bind the page to evidence. They do not grant authority or collapse verification into deployment.

• VERIFIED_LEDGER.json
• evidence-tranche5/tranche5-results.json
• tranche errata record