DatumLight

DatumLight — Lighthouses of Britain & Ireland

A retro-styled nautical reference for every lighthouse around the coasts of Britain and Ireland. DatumLight renders its data through the warm phosphor glow of a CRT terminal, presenting lighthouse positions, characteristics, and flash patterns in authentic Admiralty chart style.

CHART VIEW
An interactive nautical chart plots every lighthouse as a six-pointed star marker, colour-coded by authority — Commissioners of Irish Lights, Trinity House, Northern Lighthouse Board, and Harbour Authorities. Pan and zoom across the full coastline from Muckle Flugga to the Lizard. Graticule grid lines, cartographic wave marks, and sea area labels complete the chart aesthetic. Tap any marker to see its callout with characteristic notation and flash animation.

LIGHTS LIST
Browse the complete database sorted and filtered by name, authority, county, or range. Each entry shows the lighthouse silhouette with its actual flash pattern playing in real time — phosphor decay and all. Tap through to the full detail view with position in DM/DMS format, sector diagram, range, and signal timing breakdown.

IDENTIFY
Count the flashes. Note the colour. Estimate the period. DatumLight's identification system lets you filter by characteristic type, light colour, flash count, and period to narrow down which light you're observing from shore or sea. Results show live flash animations matched to your filter criteria.

CHART KEY
A comprehensive legend explains every symbol, colour, abbreviation, and notation convention used throughout the app — from characteristic type codes (Fl, Oc, Iso, Q, LFl, Mo) to authority colour assignments and standard Admiralty notation examples.

CONFIGURATION
Switch between green and amber phosphor themes. Both colour palettes are designed for comfortable night viewing with authentic CRT warmth.

FEATURES

Complete lighthouse database for Ireland, England, Wales, Scotland, Channel Islands, and Isle of Man
Live flash pattern animations with phosphor decay simulation
Interactive chart with coastline, graticule, sea fill, and animated wave marks
Authority colour-coding: CIL, Trinity House, NLB, Harbour Authority
Light colour display: White, Red, Green sectors
Full characteristic decoding with signal timing diagrams
Sector diagrams showing light coverage arcs
Position display in Degrees/Minutes and Degrees/Minutes/