Ambient light sensor that can send data to the 🌕 Lunar macOS app for controlling monitor brightness automatically.

Follow these steps to get the add-on installed on your system:

This add-on requires configuration for knowing where to fetch the lux data from:

1. Click on the "Configuration" tab.
2. Type in the entity ID of the lux sensor into the sensor_entity_id field.
3. Click the "SAVE" button.

Add-on configuration:

sensor_entity_id: "sensor.lux"

Set it to the entity_id of the lux sensor you want to use for adapting monitor brightness.

The entity_id of a color temperature sensor (in Kelvin). When set, Lunar can adapt the white point of external monitors to the room's light (True Tone).

The addon announces itself over mDNS as _lunarsensor._tcp, so recent Lunar versions discover it automatically the moment it starts (no configuration needed). For this to work the addon runs with host networking.

Older Lunar versions connect to the addon at homeassistant.local:8899 (since v6.2.4).

If the HomeAssistant instance is available on a different hostname, configure Lunar by running the following commands on your Mac:

defaults write fyi.lunar.Lunar sensorHostname your-homeassistant-hostname
defaults write fyi.lunar.Lunar sensorPort 8899

• Check if one-shot lux reading works

❯ curl homeassistant.local:8899/sensor/ambient_light

{"id":"sensor-ambient_light", "state":"0 lx", "value":0.000000}

• Check if the EventSource is sending lux values every 2 seconds

❯ curl -N homeassistant.local:8899/events

event: state
data: {"id": "sensor-ambient_light", "state": "400.0 lx", "value": 400.0}

event: state
data: {"id": "sensor-ambient_light", "state": "400.0 lx", "value": 400.0}

event: state
data: {"id": "sensor-ambient_light", "state": "400.0 lx", "value": 400.0}

Got questions?

You have several options to get them answered:

• The Lunar Discord Chat Server.
• The Github repository of the addon.
• The Github repository of the app.
• The FAQ section of the app