Certificate of authenticity · Verification code DNW5K78WYM · Version 1
HERE AND NOW VI
Tim Berresheim

| Inventory number | TB09/F 115 |
|---|---|
| Year | 2009 |
| Technique | Face-Mount Archival Pigment Print hinter Acrylglas, rückseitig auf Aluminium kaschiert, gerahmt. |
| Dimensions | 150 × 100 cm |
| Edition | unique |
| Issued | 13.11.2026, 08:07 |
Timestamp anchored in Bitcoin, block 975648.
Verification
- …Checksum of the certificate file
- …Artist’s signature
- …Timestamp in Bitcoin
- ·ImageDrop the image file here to compare it with the certificate.
Drop a file here: image, certificate (.json), signature (.sig) or timestamp (.ots). Nothing is uploaded; everything is computed in your browser.
Verification data
- SHA-256 of the certificate file
29225e4ebd3515939bbb86caf048fa60fe0909ccc7f4d727cc02fdd9386d1a81- Signature (Ed25519, Base64)
XVDJnSVXrsIqeA+xw0n3sK/mGjJdLw1riQvWqz7yvRF4JvJlkpoIazGHtiH2hhYQypa4VcV4a/Z0q5KUeePwDA==- Artist’s public key
0a347c3cdcf869a45213eb6eea4e65d4f60adb6d1fe7d9be59eace1f04584708- SHA-256 of the main image
f840518da5b57c9a27fb3f99b28af98103c61d4e4b4d8305259ded148a4fdfa8
How to verify this independently of this page: hash the JSON file with SHA-256; the value must match the checksum above. Verify the signature against that checksum with the public key (Ed25519). Check the .ots file together with the JSON file at opentimestamps.org: this proves since when the checksum has been in the Bitcoin blockchain. The proof depends neither on this address nor on the artist, only on certificate, key and blockchain.