skylight.

UAL794 United

Airbus A319 131 · N827UA · SFO → ?

· 1:35Quality 90side-on

3D replay

Software-steadied: the hops of the camera motor are smoothed out (plane wobble −58%). Download

Trace

Where the aircraft sat in the frame, second by second. Click the chart to jump the video there.

—FOV —az —el —pose —
Lock

Events

Tracking metrics

How well the camera kept the aircraft centred. Tap a metric for what it means and what good looks like.

Lockshare of the pass
90%
First lockfrom target selected
5.4 s
Centring, medianaz / el while locked
0.70° / 0.22°
Centring, 90th pctaz / el while locked
5.93° / 0.69°
Tightest field of viewhorizontal
4.1°
Time to 8°from first lock
3.8 s
Time to tightestfrom first lock
5.7 s
Time at telefield of view ≤ 5.5°
32.2 s
Jitter at teleaz / el, standard deviation
0.84° / 0.26°
Swing at teleaz / el, peak to peak
3.34° / 1.36°
Pan reversalsper 10 s at tele
0.0
Largest pan hopin any 1 s at tele
4.64°
Largest tilt hopin any 1 s at tele
6.79°
Pose error, mediancommand vs camera
4.42°
Largest correctionvision vs prediction
2.41°
Zoom steps
71

Aircraft & route

Flight
UAL794
Registration
N827UA
Type
Airbus A319 131
Airline
United
From
SFO
To
—
Ground speed
268 kt
Altitude at closest
6,825 ft
Vertical rate
+3,712 ft/min
Category
A3
ICAO hex
ab4c9f

Pass geometry

Max elevation
79.6°
Elevation at start → end
19.6° → 20.3°
Azimuth at start → end
359° N → 171° S
Closest-approach azimuth
87° E
Minimum slant range
2.1 km
Heading at closest
174° S
Aspect at closest
side-on (87°)
Turn
straight (7°)
Departure
Yes — climbing out after take-off
Zenith pass
No
Dead-zone wrap
No
Duration
1:35 (94.5 s)
Lock
90%

Build & tuning

The tracker build that flew this pass and the live settings that mattered, so passes can be compared across changes.

Build
2026-10-16i — lock-first on; shadow silhouette sky-masked
Commit
5610684
Node
v22.22.2
Camera
TONGVEO 20x PTZ · 1920×1080 @ 30 fps
Clip
12.9 MB · 95.0 s · offset -1.7 s
pursuit
velocity
maxLeadSec
3
panLatencySec
0.6
tiltLatencySec
0.4
rippleDeg
0.5
rippleTeleDeg
0.25
maxSpeedStepFwps
0.45
speedReachFrac
0.8
lockedSigmaDeg
0.35
sigmaGrowthDps
0.1
aimLeadSec
-0.19
correctionSlewDps
2.5
kp
1
ki
0.6

This clip and poster are © Skylight (Cameron Paczek): free for non-commercial use with credit to skylightceiling.com, not MIT. License