How to create a lightweight PDF without losing source files

1. Separate the dossier from the source archive

The dossier should be quick to open and read: cover, summary, timeline and optimised evidence copies. Source files should remain unchanged and can be downloaded in a separate ZIP archive.

This prevents irreversible compression of the only copy. The recipient gets a practical PDF, while the person preparing the dossier keeps the original files.

2. Reduce images and split volumes

Photographs and screenshots are usually the heaviest elements. The copy inside the dossier can be resized and compressed as long as all relevant text remains legible. If the result exceeds the target, split it into numbered volumes.

Archiviorum targets 10 MB or less per volume where possible. This is not a universal guarantee: one exceptionally large scan may require a different quality level or split.

• Optimised copies in the dossier
• Unchanged sources in the ZIP
• Numbered volumes where needed
• Final legibility check

3. Keep an integrity fingerprint

A manifest can record the name, size and SHA-256 fingerprint of every source file. The fingerprint does not reveal the file contents; it allows someone to verify later that the bytes have not changed.

Before sending, open every volume, check page orientation and make sure names and numbering match the index. A smaller file should never become ambiguous or unreadable.