Allsky
Role
The Allsky module drives a wide-angle (allsky) camera in a continuous loop to document the night. For each frame, it generates a weather data overlay, builds a real-time keogram and stack, then produces a timelapse video at the end of the session. Past sessions are archived and browsable.
Required devices
| Device | Role |
|---|---|
| Camera | Allsky image acquisition |
| GPS | Optional — geographic position for sunrise/sunset time calculation |
| Weather station | Optional — weather data overlaid on images and in the keogram |
Parameters
Acquisition
| Parameter | Description |
|---|---|
| Exposure | Exposure duration in seconds |
| Gain | Camera gain |
| Offset | Camera offset |
| Delay (s) | Interval in seconds between the start of two consecutive acquisitions (must be greater than exposure) |
Schedule
| Parameter | Description |
|---|---|
| Manual | Starts immediately and runs continuously while the Play action is active |
| Fixed time | Acquisition between a start and an end time (daytime or nighttime depending on the order of the times) |
| Sunset | Starts automatically at sunset and stops at sunrise |
For Fixed time and Sunset modes, the next sunrise and sunset times are computed automatically from the configured geographic position (libnova).
Geographic position
The geographic position (latitude, longitude) is required for solar time calculation. It can be entered manually or imported from a connected GPS device.
Auto exposure/gain
| Parameter | Description |
|---|---|
| Enable | Enables automatic adjustment |
| Change exposure or gain | Selects which parameter to adjust |
| Minimum value | Lower bound of the adjustment |
| Maximum value | Upper bound of the adjustment |
| Measure | Statistic used as reference (Mean or Median) |
| Target value | Target value for the statistic |
| Threshold (%) | Not currently used |
The correction coefficient is computed as: new_value = current_value × (target / current_measure).
Archives
| Parameter | Description |
|---|---|
| Keep individual images | If enabled, individual JPEGs for each session are kept in the archive; otherwise only the keogram, stack, and timelapse are retained |
Per-image processing
For each acquired image:
- FITS save of the raw image
- Overlay of date/time and weather data (temperature, humidity, pressure) in colour on the JPEG
- Maximum stack: each pixel retains the maximum value across all images of the session
- Keogram: a 1-pixel-wide vertical strip taken from the centre of each frame is appended to the previous ones to form a time-chart of the night; weather data is represented by coloured dots (red = temperature, green = humidity, blue = pressure)
- SNR log: the signal-to-noise ratio of the image is recorded with a timestamp
Timelapse
At the end of a session (manual stop or end of schedule), the module generates an MP4 H.264 timelapse video at 30 fps from all session JPEGs, using ffmpeg.
Archives
Each completed session is moved to a timestamped archive folder. Archives are browsable directly from the interface, showing for each session:
| Item | Description |
|---|---|
| Date | Timestamped session identifier |
| Keogram | Night time-strip |
| Stack | Maximum-stacked image for the night |
| Timelapse | Night video |
Weather data
If an INDI weather device is configured, the module reads WEATHER_PARAMETERS properties to retrieve temperature, humidity, and pressure. These values are:
- Displayed in real time in the Measures section
- Overlaid on each image
- Plotted in the keogram
- Recorded in a time-series graph
Actions
| Action | Description |
|---|---|
| Play | Starts the acquisition loop according to the active schedule mode |
| Pause | Temporarily suspends acquisitions without closing the session |
| Stop | Stops the session, generates the timelapse, and archives the session |