Offline Sight Reduction

1. Trip Info & Assumed Position

Date (local)

Celestial Body

Name

Label / Notes (optional, helps you find this sight later)

Latitude, assumed
(Deg / Min / N-S)

Longitude, assumed
(Deg / Min / E-W)

Timezone Offset (UTC Offset in Hours)

e.g., -4 for EDT, -5 for EST, +0 for UTC

2. Sightings & Corrections

SIGHTINGS

24h Time (HH : MM : SS) | Height (Deg / Min)

Average of Sightings

Local Time: --:--:--

UTC Time: --:--:-- UTC

Hs (Sextant Height): --° --.-'

Sextant Altitude Corrections

Index Error (IE) [Minutes / On-Off Arc]

Dip Correction [Minutes (-)]

H (Apparent Altitude): --° --.-'

Altitude Correction / Refraction [Minutes / (+/-)]

Additional Altitude Correction [Minutes / (+/-)]

Ho (Observed Altitude): --° --.-'

Offline Almanac Cache

Pre-download almanac data (GHA/Dec for the Sun, Moon, planets, and navigational stars) while you have a connection, so auto-fill keeps working offline afterward. Dates below are UTC.

From (UTC)

To (UTC)

No almanac data cached yet.

3. Nautical Almanac Data

SUN

0h UTC, Jun 2 Base (Deg / Min)

1h UTC, Jun 2 Next (Deg / Min)

GHA

Declination (Deg / Min / N-S)

Sight Reduction Results

Interp. GHA

--

Interp. Dec

--

Local Hour Angle (LHA)

--

Calculated Height (Hc)

--

Assumed Position (AP)

--

Intercept

--

Azimuth (Zn)

--

Plot

Azimuth to body Line of Position (LOP)

4. Save & Export

Import Sight from JSON

Saved Sightings (this device)

No sightings saved on this device yet.

Sight Reduction Calculator