Settings reference

Settings reference

LunarAtlas keeps settings in three places, each for a different kind of thing.

	Where	What
Your equipment and site	equipment.json	Telescopes, barlows, cameras, observing site. Edit in Settings in the app.
Your viewer edits	IMAGE.atlas.json	Per photo: hidden and moved names, colours, drawings, layer switches.
Export defaults	.env	What export should do when you do not say.

The first two are managed for you by the app. The third is for people who use the command line.

Equipment and observing site

Set in the app: Settings at the bottom of the home page, or the short form at the first close-up. The command line reads exactly the same file. See Close-ups and your equipment.

LUNARATLAS_EQUIPMENT can point at a different file, which is useful for testing.

The old .env keys LUNARATLAS_TELESCOPE, _FOCAL_MM, _EXTENDERS, _CAMERAS, _BINNINGS and _OBSERVER_* are no longer read. If you still have them, LunarAtlas warns you and says where they went.

Export defaults: .env

Create a .env in the repository root. .env.example lists every key with its default, and is generated from the single declaration of each setting, so its documented ranges are the ones actually enforced:

python3 tool_settings.py --example     # regenerate .env.example
python3 tool_settings.py --check       # the value in effect for every setting, with warnings

Export

Key	Default	What it does
LUNARATLAS_FORMAT	tiff	Output format when -o does not decide it. One of tiff, png, jpg.
LUNARATLAS_MAX_SIZE	0	Longest output side in px; 0 means 1:1. Never upscaled. 0–100000.
LUNARATLAS_AROUND_SIZE	3000x2000	View size in source px for --around NAME.
LUNARATLAS_MIN_SIZE	24.0	Smallest crater that gets a name, in output px. 4–400; 16–40 is typical.
LUNARATLAS_FONT	IBM Plex Sans	IBM Plex Sans, Source Sans 3 or Roboto (bundled), or any Google Fonts family.
LUNARATLAS_FONT_SCALE	1.0	Label size factor. 0.3–5; 0.8–1.6 is typical.
LUNARATLAS_NIGHT	dim	Names on the unlit side: hide, dim or show.
LUNARATLAS_LAYERS	area,crater,lettered,relief,landing	Which classes of names, or none.
LUNARATLAS_RIMS	1	Crater outlines in exports.
LUNARATLAS_LETTERED	1	Lettered satellite craters (Copernicus A, …).
LUNARATLAS_LANDING	1	Landing sites.
LUNARATLAS_GRID	1	Lat/lon grid in exports.
LUNARATLAS_DRAWINGS	1	Your viewer drawings and measurements in exports.
LUNARATLAS_INFO	1	Info block: date, optics, scale bar, N/E arrows.
LUNARATLAS_JPEG_QUALITY	92	JPEG quality. 0–100; 85–95 is typical.

Viewer

Key	Default	What it does
LUNARATLAS_VIEW_PORT	8766	First port to try; the next free one is used. 1024–65535.
LUNARATLAS_VIEW_OPEN	1	Open the browser when the viewer starts.

Paths and other environment variables

Variable	What it does
LUNARATLAS_DATA	Use another folder for the downloaded reference data.
LUNARATLAS_EQUIPMENT	Use another equipment file instead of equipment.json.
LUNARATLAS_TOKEN	Set the viewer's access token yourself, for scripts and tests.

Precedence

command-line option  >  environment variable  >  .env  >  built-in default

--help on any command shows the value in effect, not just the built-in default.

On/off settings have both forms on the command line (--rims / --no-rims), so a .env default can always be overridden either way.

Out-of-range values and unknown keys are reported and the default is used — LunarAtlas never silently accepts a setting it does not understand. A .env saved by Windows as UTF-8 with a byte-order mark is read correctly.

The same .env also carries settings for the companion tools (lunar_finish, mosaic_builder, panel_classifier); only the LUNARATLAS_* keys above concern this project. All 52 settings across the tools are declared once, in tool_settings.py.