Introduction

Know where every photo lives.

Obscura Trace is a macOS app that inventories your photo disks, finds duplicates and helps you consolidate your archives to a new location, without ever destroying anything without your consent.

This guide explains how to use it, screen by screen, with the exact labels you will see. It describes the app as it is today, not as it will be: when a feature does not exist yet, the guide says so.

Current version: 0.1.0, signed and notarized, released on October 4, 2026, downloadable from the Obscura member area: https://profil.obscuraflow.app/. See Installation and first launch.

Who this guide is for

• Photographers who have accumulated external disks, memory card copies and exports, and want to know what they actually own.
• Archivists and picture researchers who must consolidate a collection without losing a single original or a single editing file (XMP).
• No technical skills are needed for chapters 1 to 7. Chapter 8, on the command line, is for advanced users.

The safety promises, in plain terms

Obscura Trace handles irreplaceable archives. It is designed as backup software, not as a mere file utility. In practice:

1. Nothing is deleted without your consent. The analysis and the Centre de revue (Review Center) only read your files and record your decisions in the catalog. In the app, only the Centre de transfert (Transfer Center) can write to a disk, and only after a confirmation screen that you approve.
2. The Trash by default. When you move photos, the originals go to the disk’s Trash, from which you can recover them. The app never empties the Trash. Permanent deletion exists, but it is disabled by default, must be allowed in the Réglages (Settings) and accepted again for each transfer.
3. Copy, then verify, and only then remove. A move is always a copy followed by a verification of the content (SHA-256 fingerprint); the original is removed only once the copy has been verified. A file being copied carries a temporary name (.obscura-part) and never takes its final name before it is verified.
4. Nothing is silently overwritten. If a file with the same name already exists at the destination, the app compares the contents by default; if they differ, the operation is set aside and nothing is overwritten. Replacement happens only if you explicitly asked for it, and the old version goes to the Trash.
5. Everything is logged, before acting. Each operation on a file is written to a journal before it is performed. If the disk is unplugged or the Mac shuts down, the resume knows exactly where it left off. A readable history of operations is shown in the Activité (Activity) screen.
6. 100% local operation. Your photos, your metadata and your catalog never leave your Mac. No analysis engine uses the network. The only possible connection is the check for updates, disabled by default, which only consults the list of published versions.

Contents

Conventions used in this guide

• The labels in quotation marks “…” are those of the app, copied from the source code.
• The screenshots (images/) are taken from the real app, with a demonstration collection, by make screenshots: they are regenerated each time the interface changes. Two placeholders remain marked as comments: the DMG window and the updates menu, which no scenario captures yet.