An observatory can have several answers to “is it safe?” There might be a weather service, another monitor watching the building, and a network between them and the imaging computer. Combining those answers needs some care: a missing response is different from a fresh response that says unsafe.

NINA Field Kit brings those sources together in N.I.N.A. It also adds a separate tool for the imaging sequence: an autofocus trigger with an absolute HFR limit. The 0.1.0.9 release puts that check in the Advanced Sequencer’s Triggers list.

One safety result, several required sources

Choose Field Kit Alpaca Safety Monitor in N.I.N.A.’s Safety Monitor panel and add the Alpaca sources you want to use. Every enabled source is required: the combined result becomes safe only when all of them meet their policies. Startup is unsafe until fresh readings satisfy the recovery requirements.

Polling happens in the background. Refreshing N.I.N.A.’s display reads the local result without sending another request to each server. Setup exposes the polling interval, retry behavior, age limit for safe readings, and the confirmation needed before returning to safe.

With the defaults, a check gets three attempts and two exhausted checks can be tolerated. A separate 90-second evidence-age limit still runs during retries. Those two tolerated misses do not buy another 90 seconds after the connection fails. A valid unsafe reading withdraws safety immediately by default; returning to safe requires three consecutive safe readings and the configured hold time.

The monitor guide explains the policy and setup. Field Kit reports the result to N.I.N.A.; configure and verify the Advanced Sequencer’s response separately. The plugin does not itself park a mount, close a roof, or stop acquisition.

Put a ceiling on autofocus HFR

The other part of Field Kit is AF above HFR. Add it to an imaging container’s Triggers and enter a positive Maximum HFR. Before the next light exposure, it checks the latest image or completed autofocus HFR. Above the limit, it runs autofocus; at or below it, imaging continues.

If the new autofocus result is unusable or still exceeds the limit, the trigger fails through N.I.N.A.’s sequence failure handling. It does not keep refocusing indefinitely. A connected unsafe safety monitor or an imminent meridian flip defers the focus run.

The check uses the autofocus report’s fitted HFR, rather than a separate verification exposure. Use Star HFR mode and choose a limit appropriate to the rig: the history is session-wide, without filter, target, binning, or age restrictions. The trigger guide covers those details. When upgrading from the older sequence instruction, replace it with the trigger explicitly; saved instructions are not moved automatically.

Installation and diagnostics

Field Kit requires Windows and N.I.N.A. 3.2.0.9001 or newer. Add https://nina-plugins.psf-guard.com/ under Options → General → Plugin Repositories, refresh the available plugins, install Field Kit, and restart N.I.N.A. This release uses the theatr.us registry rather than the default community catalog. Published DLLs are code-signed.

For troubleshooting, the monitor shows evidence age, retries, missed checks, and recent events. Diagnostic exports omit endpoint URLs, credentials, headers, and response bodies, while retaining source labels.

The source is Apache-2.0 licensed. For camera recovery, see ZWOgain; the astronomy software page collects the rest of the tools.