Sensor-physics baselines & citations
The numbers behind the readings
When Auriginal shows a plain-language reading on a verification page — “location pinned to ~2.6 m,” “gravity 9.8 m/s²,” “magnetic field 30 µT” — it is comparing a signed sensor value against a real-world baseline. Every baseline traces to a government agency, an international standard, peer-reviewed research, or an official Apple specification. They are listed here so any reading can be checked against its source.
1. Earth's magnetic field magnitude Hard
~25–80 µT as a real phone reads it. Earth's core field is ~25–65 µT at the surface (up to ~70 µT near the poles, ~25 µT near the magnetic equator); local steel, vehicles and electronics add tens of µT, so genuine outdoor and everyday readings commonly run to ~80 µT. Readings in that band are treated as normal; outside it is flagged unusual.
Earth is a giant weak magnet; a real phone reads roughly 25–80 µT once nearby metal and location nudge the core 25–65 µT field — a fingerprint of a real place.
The core 25–65 µT surface range is established fact; the ~80 µT upper is that range plus qualitative local distortion (“tens of µT” from nearby metal), not a fixed constant.
Sources: USGS FS-236-95 NOAA/NCEI World Magnetic Model NCEI Geomagnetism FAQ
2. Standard atmospheric pressure & pressure–altitude Hard
Sea-level standard = 1013.25 hPa (29.92 inHg) at 15 °C. Pressure falls ~12 hPa per 100 m near sea level.
Air pushes down at a known standard pressure at sea level and thins out predictably as you climb; a barometer that tracks altitude the way physics says is behaving like a real one.
The International Standard Atmosphere is a formal standard; the sea-level value is exact by definition. Weather varies ±~30 hPa day to day (normal).
Sources: ICAO Doc 7488 / ISO 2533 (International Standard Atmosphere) · NOAA National Weather Service glossary (1013.25 hPa sea-level standard)
3. Illuminance (lux) for common scenes Soft Hard (office)
Direct sun ~32,000–100,000 lux; full daylight ~10,000–25,000; overcast ~1,000–2,000; sunrise/sunset ~400 down to ~1–10; typical office 300–500 lux (design standard); clear full-moon night ~0.25–1.
Sunlight is thousands of times brighter than a lit room, which is thousands of times brighter than moonlight — a photo's brightness should match the scene it claims to show.
The office figure is a genuine standard (Hard). Outdoor values are nominal ranges (Soft — daylight varies with sun angle, cloud, and season); CIE standardizes sky distribution, not absolute lux.
Sources: IES recommended illuminance & EN 12464-1 (office 300–500 lux); CIE Standard Overcast Sky and Clear Sky
4. Civilian GPS horizontal accuracy Spec
Signal-in-space worst case ≤7.8 m at 95% (U.S. government guarantee); typical modern smartphone ~4.9 m radius under open sky (estimate); high-quality receivers ≤2.168 m. Degrades near buildings and trees.
A phone GPS pins you to within about a car-length under open sky — enough to place a photo, but it can't fake a location without the physics lining up.
≤7.8 m is an official commitment; the ~4.9 m smartphone figure is gps.gov's stated typical device performance (estimate).
5. Selfie / arm's-length capture distance Soft
~25–50 cm from the face (bent arm ~30 cm, extended ~50 cm); anthropometric arm reach caps ~70 cm. Explicitly an estimate.
You physically can't hold a phone more than about half a meter from your own face — a genuine selfie's depth falls in a narrow, arm-length band.
Apple's 25–50 cm (published for Face ID) is the best authoritative anchor; ~70 cm is a hard anthropometric ceiling.
Sources: Apple — About Face ID advanced technology U.S. Army / UMTRI ANSUR anthropometry
6. iPhone depth-sensing ranges Spec
TrueDepth (front) effective ~25–50 cm for faces (useful ≤~1 m); LiDAR (rear Pro) maps a room up to ~5 m indoors (approximate).
The front sensor is tuned for a face at arm's length; the rear LiDAR maps a room out to about five meters — both leave a real 3D depth signature a flat photo of a surface can't.
TrueDepth 25–50 cm is official spec. LiDAR “~5 m” is Apple's operational range (condition-dependent); presented as “approximately 5 m.”
Sources: Apple Face ID doc Characterization of the iPhone LiDAR-Based Sensing System (NIH/PMC)
7. Ambient sound levels (dB) Soft
Quiet room ~30–40 dBA; normal indoor / conversation ~50–60 dBA; busy street / traffic ~70–85 dBA. EPA benchmarks: ~45 dBA indoors / ~55 dBA outdoors; >70 dBA sustained risks hearing loss.
A quiet room, a chatty room, and a busy street each sit in a distinct loudness band — a video's soundtrack should match the place it claims to be from.
EPA 45 / 55 / 70 dBA are official reference levels; the room / conversation / traffic numbers are typical illustrative levels (estimate) from government health agencies.
Sources: U.S. EPA 550/9-74-004 CDC/NIOSH noise
8. Human hand tremor / hand-held micro-motion Hard
Physiological tremor has a characteristic ~8–12 Hz neural component (weaker bands ~2–4 Hz, ~20–25 Hz). Added device mass lowers amplitude but not the frequency.
No one can hold a phone perfectly still — a real hand-held shot carries a tiny, unavoidable 8–12 Hz shake a static or synthetic source doesn't.
The 8–12 Hz band is well-established; amplitude varies by person, posture, and mass, so the robust invariant is the frequency band.
Sources: Neuroscience Letters (8–12 Hz component) PubMed 11018494 Smartphone-measured tremor spectrum (NIH/PMC)
9. Typical walking speed Hard
Comfortable adult walking ≈ 1.3–1.4 m/s (~5 km/h); meta-analytic usual pace 1.31 m/s; range ~1.1–1.65 m/s.
People walk at a remarkably consistent ~1.4 m/s — motion in a real walking video should move the world by about that much per second.
Strong peer-reviewed support; quoted as a ~1.3–1.4 m/s central value with normal spread.
Source: Outdoor Walking Speeds of Apparently Healthy Adults — Systematic Review & Meta-analysis (NIH/PMC)
10. iPhone main (wide) camera FOV / focal length Spec
48 MP main, 24 mm-equivalent focal length, ƒ/1.78. 24 mm-equiv ≈ ~84° diagonal / ~74° horizontal / ~53° vertical angle of view (geometrically derived).
The iPhone's main camera sees the world through a fixed 24 mm-equivalent window about 84° wide — a real photo's geometry has to be consistent with that lens.
Focal length, megapixels, and aperture are official specs; FOV in degrees is derived (“approximate, calculated from the 24 mm equivalent”).
11. Standard gravitational acceleration Hard
g₀ = 9.80665 m/s² (standard gravity, exact by definition). Actual surface gravity varies ~9.78 m/s² (equator) to ~9.83 m/s² (poles). A phone at rest reads ~1 g on its accelerometer.
Gravity pulls everything down at a steady, known rate; a phone that's really being held feels that constant ~1 g pull — a basic reality check that it's a physical device in the world.
g₀ is exact by definition; local surface gravity varies ~±0.3% with latitude and altitude (expected, not anomalous).
Source: NIST CODATA — standard acceleration of gravity (9.80665 m/s²)
Every user-facing baseline maps to an entry above. Read the tier explainer for how the grades relate to these readings.