Istanbul's Duplicate Image Crisis: The Key Decisions That Will Shape the City's Digital Heritage

Istanbul's cultural memory has a duplication problem. Across the digital archives maintained by the Istanbul Metropolitan Municipality, the SALT Research center in Beyoğlu, and several university libraries along the Bosphorus, conservators have identified tens of thousands of duplicate and near-duplicate image files — scanned photographs, digitized postcards, and architectural survey images — many of which exist in two, three, or even five conflicting versions, with different cropping, colour calibration, and metadata. The question of what to do with them is no longer academic. Budget cycles and a major digitization audit scheduled for completion by September 2026 are forcing a decision.

The stakes are higher than they might appear. Istanbul sits at the intersection of several pressures that make getting this right urgent: the 2023 Kahramanmaraş earthquakes accelerated demand for reliable pre-disaster architectural documentation, the city's tourism economy depends on authoritative heritage imagery, and a lira that has lost roughly half its purchasing power against the euro since 2021 means institutions cannot afford to redo expensive scanning work. Every wasted digitization effort carries a real cost. Choosing the wrong canonical image — or deleting a file that turns out to be the only surviving scan of a demolished structure — is not recoverable.

Where the Problem Is Most Acute

The duplication crisis is concentrated in three overlapping collections. SALT Research, housed in the former Ottoman Bank building on Bankalar Caddesi in Karaköy, holds one of the city's largest open-access photograph databases, with more than 400,000 digitized items. The Istanbul Archaeological Museums, whose administrative offices sit within the Topkapı Palace compound in Sultanahmet, have been running their own parallel digitization program since 2019. And the Atatürk Library in Taksim, which underwent a controversial restoration completed in 2021, holds municipal photographic archives that overlap significantly with both. When staff at any one institution photograph the same original print — sometimes unaware the other has already done so — the city ends up with multiple digital objects representing a single physical artifact, none of them flagged as authoritative.

The problem is compounded by format fragmentation. Some scans were produced at 300 dpi for web display; others were done at 600 dpi for archival preservation. Metadata standards differ: SALT uses Dublin Core, while the municipal system defaults to a locally adapted schema that does not map cleanly onto international library standards. A researcher requesting images of, say, the Galata Tower for a restoration study currently has no reliable way to know which version of a given scan has been reviewed by a conservator and which was uploaded by a volunteer during a 2020 crowdsourcing sprint.

The Decisions That Cannot Wait

Three choices will define how this gets resolved — or doesn't. First, institutions must agree on a single deduplication standard before the September audit closes. The leading proposal, circulated internally among the three major collections, would designate one master record per original physical item and demote all others to derivative status rather than deleting them outright. This preserves the variant scans — which sometimes capture different tonal information — while establishing a clear hierarchy. Second, someone has to fund the crosswalk: the technical labor of mapping metadata between incompatible systems. Estimates from comparable projects in European city archives place this at roughly €80,000 to €120,000 for a collection of Istanbul's scale, a figure that would require either municipal budget approval from the Istanbul Metropolitan Municipality or a grant application to the European Union's Creative Europe program, for which Turkey remains an eligible country despite its suspended accession process.

Third — and most politically charged — is the question of governance. The Istanbul Metropolitan Municipality is controlled by CHP, while the national ministries that oversee the Archaeological Museums and some heritage funding operate under the AKP government. Agreements on shared standards require both sides to cooperate at an institutional level even when the political relationship is strained. Previous joint digitization efforts, including a 2022 initiative linking municipal and ministry collections around the historic peninsula, stalled partly for this reason.

Conservators and archivists following the audit have a narrow window. If the September deadline passes without a governance agreement, the three collections will each proceed independently, locking in incompatibility for another budget cycle — likely until 2028 at the earliest. The images of old Istanbul will still exist. The question is whether anyone will be able to find the right one.