Berlin's Duplicate Image Crisis: The Key Decisions That Will Shape the City's Digital Archives

Berlin's public sector is sitting on a sprawling, largely ungoverned mess of duplicate digital images. Across municipal departments, cultural institutions and the broader Berlin Senate administration, redundant photograph files have accumulated for years inside shared servers, often stored in multiple formats, under conflicting file names, catalogued by different departments using incompatible metadata standards. The problem is not abstract. It costs money, slows down archivists and, in at least one documented case, led the Landesarchiv Berlin to publish the wrong version of a historical photograph in an official publication — a corrected edition had to be issued in the spring of 2025.

The stakes are higher than they might seem. Berlin is in the middle of a multi-year digitisation push. The Kulturprojekte Berlin GmbH, which coordinates digital access to the city's cultural heritage, has been expanding its online platforms, and the Berlin State Library on Potsdamer Straße is processing tens of thousands of image files as part of its ongoing retrospective digitisation programme. If duplicate images are not systematically identified and resolved before those collections go live, errors compound. A misidentified photograph of a 1960s Kreuzberg street scene, replicated a dozen times across different departmental servers, becomes exponentially harder to correct once it has been indexed by external search engines and embedded into third-party educational resources.

The Technical and Political Problem

Deduplication software exists. The Berlin Senate Department for Digital Transformation has been piloting algorithmic tools since at least late 2024, working with the IT service provider ITDZ Berlin, which manages infrastructure for most of the state's digital operations. The technology can flag near-identical images — accounting for minor differences in compression or cropping — with reasonable accuracy. The harder question is what happens after the flag: who has the authority to delete a file, who bears legal responsibility if the wrong version is destroyed, and which metadata standard governs the surviving copy.

That governance gap is the crux of the current debate inside the Senate. Three separate departments — the Senate Chancellery's digitalisation unit, the Senator for Culture, and the Senator for the Interior, which oversees the Landesarchiv — each have a legitimate claim over parts of the affected collections. As of July 2026, there is no single coordinating body with binding authority to resolve those overlaps. A working group established under the 2023 Berlin E-Government Act has met quarterly but has not yet produced enforceable guidelines on image deduplication protocols, according to documents reviewed by The Daily Berlin.

The numbers give a sense of scale. ITDZ Berlin's own infrastructure reports have referenced storage costs for the Senate's collective data estate running into tens of millions of euros annually, though the share attributable specifically to redundant image files has not been broken out publicly. Archivists at the Stadtmuseum Berlin, which holds the city's principal historical photograph collection and operates sites including the Ephraim-Palais in the Nikolaiviertel, have estimated internally that duplicate files account for a significant fraction of their active digital storage load — figures that have circulated in internal working papers but have not been formally published.

What Comes Next

The decisions that now need to be made fall into three broad categories. First, the Senate must settle on a governance structure — most likely assigning a lead agency, with ITDZ Berlin as the technical executor — before the end of the year, ahead of the next budget round in autumn 2026, when departments will be bidding for digitisation funds. Second, a binding metadata standard has to be adopted. The most widely discussed candidate is a Berlin-adapted version of the LIDO XML schema already used by several German federal museums; adopting it would align the city's collections with the Deutsche Digitale Bibliothek, simplifying future data sharing. Third, the Senate needs a retention policy with real teeth — specifying not just how to identify duplicates but what the default action is, who approves exceptions, and how decisions are logged for accountability.

For institutions like the Stadtmuseum and the Zentral- und Landesbibliothek on Breite Straße, the practical consequence of delay is straightforward: more storage costs, more cataloguing errors, and more time spent by underpaid archivists manually reconciling files that software could flag in minutes. The technical solution is available. The political will to use it is what the next six months will test.