Translation settings

Translation is the only stage in Lumina that calls an external AI API. Detection, OCR, inpainting, and typesetting run fully offline; translation sends only the text segments you choose to the provider you configure.

Configure everything under Settings → Translation.

Providers

Provider	Compatible with	Notes
Custom	Any OpenAI- or Anthropic-compatible API	Bring your own base URL — Ollama, LM Studio, vLLM, OpenRouter, etc. An "Anthropic style" switch is available for Anthropic-compatible endpoints.
OpenRouter	OpenRouter	Uses your OpenRouter key and model
Groq	Groq (GroqCloud)	Uses your Groq key and model
Gemini	Google Gemini	Uses your Gemini API key — see How to get your API key for a free-tier example

Providers load on demand: Lumina only imports the SDK for the provider you actually use, so switching providers — or running local-only models — has no startup cost for the others.

API keys

• Keys are entered once in translation settings and stored in Lumina's local secrets vault, encrypted with your operating system's credential facility (DPAPI on Windows, Keychain on macOS, libsecret on Linux), then persisted to secrets.json in the app's user-data folder.
• If the OS encryption facility is unavailable, Lumina falls back to base64 obfuscation rather than failing.
• Keys are never written to project files (.lmi) and never sent anywhere except directly to the provider you configured, as a request header.

How to get your API key

Each provider issues keys from its own dashboard — the exact steps differ per provider, but the flow is always the same: create a key on the provider's site, then paste it into Settings → Translation.

As an example, here is how to get a Gemini key. We recommend Gemini for getting started because Google AI Studio's free tier offers a large monthly quota at no cost — plenty for casual translation.

Gemini (Google AI Studio)

1. Open https://aistudio.google.com/app/apikey and sign in with a Google account.
2. Click Create API key. If asked to pick a Google Cloud project, choose one or let AI Studio create a new one automatically — either works.
3. Copy the key right away. It starts with AIza... and is only shown once; if you lose it, delete it and create a new one.
4. In Lumina, open Settings → Translation, set Provider to Gemini, paste the key, and pick a model (e.g. the latest Gemini Flash).

The free tier gives you a monthly quota of requests and tokens that resets automatically. Hitting the limit just means waiting for the next reset — or upgrading to a paid tier if you need more.

Target language and style

• Pick the target language for translation; it is stored per project (a non-secret setting embedded in .lmi files).
• A style / instruction field controls how the model translates. Lumina ships a default instruction file (prompts/translate-default.md) that you can load, and you can write your own to enforce terminology, tone, honorifics, or formatting rules.
• When translating, Lumina sends the preceding dialogue as context so names and phrasing stay consistent across bubbles.

Privacy

Only the text of the page you translate is sent to your provider — never the page image, and never any model or project data. Read more in the Privacy Policy and the General FAQ.