Timestamp photos, series, and image collections
Dated proof of prior authorship for photos already taken — €2, no signup, verifiable by anyone. For artistic series, personal archives, or image folders you need to preserve.
Positioning note: this page deals with anchoring already-existing photos — series, archives, collections, image folders. For real-time state-of-evidence capture (property check-in, accident scene, received delivery), the mechanism remains valid but other tools are better suited to live mobile workflows.
The situation
You're a photographer — recognized professional, dedicated amateur, or simply the holder of a series of photos that matter to you. You want to prove, on a specific date, that you held these photos in this form.
A few typical contexts:
- Photographer finalizing a series before publishing on Instagram, Behance, or a portfolio website, who wants proof of prior authorship before first publication.
- Archive author (families, associations, collectors) digitizing an old collection and wanting to timestamp the whole to guarantee its integrity and the date of digitization.
- Online seller (Vinted, eBay, marketplace platforms) taking detailed photos of a valuable item before shipping, to hold proof of its state at departure.
- Individual documenting damages, nuisances, or any event they want to be able to produce later without challenge to the date.
- Journalist, investigator, whistleblower wanting to timestamp a sensitive photo dossier without depending on a third-party platform.
- Visual artist or NFT creator wanting to anchor the original version of a work before any circulation.
The common legal denominator: being able to demonstrate, on an opposable date, that these images were in your possession in this exact form.
The real risk
Most jurisdictions following the Berne Convention protect photographic works from the moment of creation. Under French law (Art. L.112-2, 9° of the CPI), this includes "photographic works and works created using techniques analogous to photography". But this protection is conditional on demonstrating the photograph's originality — proof that the image reflects the free and creative choices of its author.
The Court of Justice of the European Union clarified this in Eva-Maria Painer (CJEU, December 1, 2011, C-145/10). The Court indicated that a photograph is protected if it constitutes "the author's own intellectual creation reflecting their personality and manifesting through free and creative choices" made at different stages:
- Preparatory phase: choice of staging, subject pose, lighting
- Moment of capture: framing, angle, atmosphere, timing
- Post-processing: development techniques, editing
Practical consequence: a purely standardized or constrained photograph (catalog shot, administrative scan, ID photo) may not be protected by copyright for lack of demonstrable originality. A recent ruling by the Tribunal judiciaire de Paris on February 18, 2026 (RG 24/12841) reminded this requirement by dismissing a photographer's claim concerning thousands of catalog photos. But a series marked by an aesthetic stance, a singular visual approach, and personal choices of framing and light will be protectable — provided one can prove it.
This is where proof of prior authorship of the creative process changes everything.
The EXIF question — and why it isn't enough
Digital photo files embed EXIF metadata (Exchangeable Image File Format): date, time, camera model, capture settings, and sometimes GPS location. Many photographers believe these metadata alone constitute proof of prior authorship.
They don't.
The French Court of Appeal of Versailles, in a ruling of May 4, 2006 (RG 05/02498), held that "EXIF data alone does not allow determining whether [the photographer] is the author of the photograph in question". The technical reason: EXIF metadata can be modified with any basic software, with no trace of modification. They constitute an indicator, never a reliable proof on their own.
This is exactly what ETcH solves. By anchoring the SHA-256 hash of the photo file (which intrinsically includes its EXIF), you don't prove that the EXIF is truthful — you prove that this exact file, with these exact EXIF, existed in this state on an opposable and verifiable date. Any subsequent modification of the file — even a single pixel, or a single EXIF field — changes the hash and breaks the proof. Conversely, if a file produced in court has the same hash as the anchored one, its integrity since anchoring is mathematically demonstrated.
What you can anchor
For a photo or photo dossier, what matters often goes beyond the final file:
For photographers (series and works)
- Original RAW files (Canon CR3, Nikon NEF, Sony ARW, Fujifilm RAF, DNG...)
- Developed versions (TIFF, PSD, high-resolution JPEG exports)
- Explored and rejected edit variants
- Contact sheets
- Capture notes, scouting, series concept
- Model releases or image-rights authorizations (signed PDFs)
- Filled IPTC metadata (captions, keywords, copyright)
- Editorial notes (concept, intent, references)
For archives and collections
- High-resolution digitizations of a collection
- Inventories as frozen PDF
- Descriptive notices linked to each image
- Classification and cataloging plans
For other uses
- Photos of items before sale or shipping
- Visual documentation of an event
- Photographic dossier of investigation, reporting, testimony
- Any series of images you want timestamped in a sealed way
Why the bundle changes everything
A single photo proves that you held that shot on a given date. A bundle that brings together the contact sheet, two or three alternative RAWs, the retained version, capture notes, and intent statement demonstrates a photographic approach — exactly what Painer jurisprudence requires to characterize originality.
For archives, the bundle is even more relevant: anchoring 50 or 100 digitized photos in a single anchoring for €2 produces a sealed chronology of the collection, where anchoring them one by one would be both costly and unnecessarily granular.
For €2 — the price of a single anchoring — you can fit up to 50 MB of files in one bundle. High-resolution JPEGs or even a few developed RAWs easily fit within that envelope for a complete series.
A real case
A photographer finalizes a series of forty-five images after a three-week trip. Before publishing the first ones on Instagram and submitting the series to several galleries for exhibition, they gather in one folder: original RAW files of the retained images, final developed JPEG high-resolution versions, the complete contact sheet, their intent note for the series, signed authorizations from a few photographed people.
The set totals 38 MB. They anchor it on ETcH for €2.
Three months later, they discover that one image from the series has been reproduced without consent on an online magazine, artificially backdated to suggest it predated their own publication. The hash of their original file, anchored on Ethereum three months earlier, mathematically proves they held this image on that specific date. The contact sheet and intent note, in the same bundle, additionally demonstrate the photographic approach and aesthetic stance required by Painer jurisprudence for copyright protection.
From there, several remedies exist — most without a lawyer and without court — to stop the unauthorized reuse or seek compensation.
For the European IP angle, the Tribunal judiciaire de Marseille decision of March 20, 2025 (AZ Factory v. Valeria Moda, RG 23/00046) recognized the probative value of blockchain timestamps to establish prior authorship of original creations. The case concerned fashion sketches, but the legal principle applies to any digital work — including photography.
Alternatives to know
For photography, several solutions exist in the market, which are worth mentioning honestly:
Content Credentials / C2PA (initiative led notably by Adobe, Sony, Nikon, Canon, Leica, Microsoft, BBC): cryptographic signature at the moment of capture on compatible bodies, and through edits in Photoshop / Lightroom. The integrated pro-workflow approach.
eIDAS-certified mobile evidence services (CertiPhoto, Certifiles, and similar): mobile app producing evidence with qualified eIDAS timestamp and geolocation at capture time. The real-time certified approach.
France's e-Soleau envelope (INPI): digital file deposit up to 300 MB per envelope, valid 5 years renewable. The administrative French approach.
The approaches don't exclude each other: a photographer might use Content Credentials on their camera body for everyday production, and ETcH to timestamp complete series in bundle form at the moment they consider them finalized.
How to use it
Finalize your selection in the version you want to protect. For RAW files, keep them as-is. For developed versions, export as high-resolution JPEG or TIFF — note: some software modifies metadata on every opening.
Gather the project files you consider relevant to the proof: RAW files, developed versions, contact sheets, capture notes, authorizations, intent note.
Drop them on etchproof.eu SHA-256 fingerprints are computed in your browser — no file ever leaves your machine.
Keep the proof ZIP delivered after anchoring. It contains the PDF certificate, the manifest, the Ethereum transaction, and your original files. This is what holds up in case of dispute — keep at least two copies, in two different locations.
Honest limits
ETcH timestamping proves prior existence, not authorship. To support authorship in a dispute, you'll often need other elements: witness statements, correspondence, evidence of iterative design — which is exactly what bundling enables.
Timestamping does not replace a bailiff's report (or your jurisdiction's equivalent) if the dispute goes to court. But that report can be issued months or years after the anchoring: in the AZ Factory case, the bailiff's report came more than fourteen months after the original anchoring. You pay €2 now — and only the cost of the report (typically a few hundred euros) if a dispute actually arises.