Remote viewer

The remote viewer is the public face of a caelum camera network: a read-only website that shows every camera publishing to one archive — the latest image from each, and for every camera a browsable history of nights with keograms and frame galleries.

AstroMeters runs one at viewer.caelum.astrometers.eu.

What it shows

• All cameras — one card per camera with its name, latest thumbnail and when it last published. Each camera also gets its own entry in the sidebar, so comparing cameras is one click.
• A camera — its site coordinates, a strip of observation dates (newest selected by default), that night's keogram and a gallery of the day's thumbnails.
• Overlays — the overlay each camera rendered is stacked over its frames, exactly as in the camera's own web UI, and can be toggled off.

Screenshots show the mock backend's synthetic frames, captured in daylight — hence no keogram yet.

How it works

There is no server behind it. The viewer (web/apps/remote-web) is a static single-page app that reads three kinds of JSON file and the images they point to, all produced by the cameras' uploader:

File	Written by	Contents
cameras.json	every camera, merged	the list of cameras, each with its latest thumbnail
<slug>/manifest.json	that camera	site, and the dates it has data for
<slug>/<date>/index.json	that camera	the frames of one observation day

So the viewer can show nothing that is not already public in the archive, and it holds no credentials. It has no write path at all. A camera appears in the viewer as soon as its first upload lands — there is nothing to register.

Publishing a camera

Point the camera's upload at the archive the viewer is served from and give it a slug and a name:

{
  "upload": {
    "enabled": true,
    "remote_host": "archive.example.org",
    "remote_user": "caelum",
    "remote_base_path": "/var/www/allsky-data",
    "camera_slug": "brno-north",
    "camera_name": "Brno North Allsky"
  }
}

camera_slug is the camera's directory in the archive and its address in the viewer (/#/camera/brno-north); camera_name is the label people see. SSH keys, transports and the full layout are in Upload & archive.

Want your camera on viewer.caelum.astrometers.eu? Contact AstroMeters at info@astrometers.eu.

Location is public

Each camera's location ends up in its public manifest.json. If the site is somebody's garden, set location to a rounded coordinate — the sky-state calculation does not need metre precision.

Running your own

The viewer is one build that works wherever its folder is dropped — at a document root or in a subdirectory, with no rebuild and no web server configuration, because it derives the data root from its own URL and keeps its routes in the URL fragment.

cd web
pnpm --filter remote-web build
rsync -az apps/remote-web/dist/ archive.example.org:/var/www/allsky-data/

No --delete: the cameras' data lives in the same tree. The Apache vhost and the upload user are in Deployment.