Dome & Mount Geometry → NINA Settings

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Feature list

• Physical-measurement or direct-entry workflow for calibrating dome/mount geometry
• Live conversion to NINA's exact signed Options → Dome fields, with one-click clipboard copy
• Real-time dome-azimuth and shutter-clearance calculation, ported from NINA's own sync math
• Interactive 3D observatory model — dome, wall, floor, OTA, optical axis, shutter door, aperture footprint
• Dual-saddle support with independent clearance checking for both OTAs
• GEM and Alt/Az/Fork mount support, including meridian-flip pier-side handling (manual or auto)
• Local horizon modeling — flat minimum or full custom profile (.hrz/CSV)
• Automatic pointing constraints: can't point below the horizon or at a non-rising declination
• Full-sky coverage sweep, split by pier side
• Celestial equator and elevated-pole reference lines, both genuinely latitude-aware
• Save/Load complete setup as a portable JSON file; Reset to Defaults

What this tool does

NINA can slave your dome to your telescope, but only if it knows precisely where your mount sits relative to the dome's center. Getting those numbers right by hand is easy to get wrong. This tool converts either a physical measurement or values you already have into the exact signed fields NINA's Options → Dome tab expects, then shows you live whether your shutter will actually clear the OTA at any given pointing.

Getting started

Save Setup / Load Setup exports everything as a JSON file, or restores it. Reset to Defaults reloads with every field back to its starting value. The status banner just below the title tells you at a glance whether the current pointing is valid: green for everything clears, amber for "pointing was adjusted," red for a real problem.

Step 1 — Mount Position

"I'll measure my dome" — plumb-bob the dome's true center and the mount's RA/Dec intersection down to the floor, mark them, then measure heights and the straight-line N/S and E/W distance between the marks (true north, not magnetic).

"I already have my NINA values" — type in the signed values directly.

Step 2 — Dome & Rotator

Dome radius (center to rim), shutter width (straight-line, not arc), rotator precision / Azimuth Tolerance, and wall height (affects 3D preview only, not the NINA math).

Step 3 — Optical Axis Offset

GEM — GEM Axis Length, measured with the mount slewed 90° from the meridian. Alt/Az or Fork — Dec Horizontal Offset. Dual saddle reveals the Lateral Axis Length field and lets you choose which OTA NINA tracks.

Step 4 — Telescope Pointing

Two modes — Hour Angle + Dec, or Point at Alt/Az — with a jog pad (0.1°/1°/5°/15° steps, hold to keep moving). Pier side is manual by default; "Auto-flip at the meridian" resolves it automatically.

Local Horizon

Flat minimum altitude, or a full custom profile loaded from a .hrz file (same format as Stellarium). Shown in the 3D view as a wireframe skyline.

Sky Coverage

Collapsed by default. Sweeps the entire sky for both pier sides side by side.

3D Preview

Drag to orbit, scroll to zoom. The shutter turns red whenever it doesn't clear. Toggle the local horizon and celestial equator from the preview header.

NINA · Options → Dome panel

The final answer — Copy NINA Settings copies all eight values to your clipboard as clean, pasteable text.

Tips

• The status banner is the fastest sanity check — green means done, otherwise it tells you exactly which problem to fix.
• Run Sky Coverage before your first real night out, especially with a dual-saddle setup.
• Save your setup once it's dialed in.
• Wall height only affects the 3D preview, not the NINA math.