Istanbul's Duplicate Image Problem: The Hidden Numbers Draining City Archives and Tourism Budgets

Tens of thousands of duplicate image files — some estimates from archivists working with Istanbul Metropolitan Municipality put the figure above 80,000 redundant assets — are clogging the digital storage systems used by the city's cultural and tourism bodies, a problem that has quietly compounded costs and delayed public-access projects for at least three years. The scale of the duplication only became measurable after a system audit commissioned in early 2026 began cross-referencing holdings across multiple municipal departments.

The timing matters. Istanbul is midway through a broader digitisation programme tied to its bid to deepen cultural tourism ahead of the projected 20-million-visitor milestone for 2027. Redundant imagery wastes server space, inflates licensing checks, and — critically — means restoration teams sometimes work from degraded copies of heritage photographs rather than the highest-resolution originals. When the Galata Tower's conservation unit needed archival facade images last autumn, staff reportedly spent three working days navigating duplicate folders before locating the master files.

Where the Data Comes From — and What It Shows

The Istanbul Metropolitan Municipality's Department of Cultural Heritage and Museums manages digital repositories covering sites from Sultanahmet to the Byzantine land walls in Topkapı. According to the municipality's published 2025 budget documents, digital infrastructure spending reached 47 million Turkish lira, a figure that includes storage, licensing, and staff time. Archivists who have spoken publicly at professional forums — including a February 2026 panel hosted by the Istanbul Technical University — have flagged that duplicate-image overhead can account for between 15 and 25 percent of raw storage costs in large municipal systems, though no Istanbul-specific audited figure has yet been released.

The İBB's open data portal, which launched a heritage photography section in March 2025, currently lists more than 340,000 image records covering Ottoman-era structures, Bosphorus waterfront changes, and neighbourhood surveys from Beyoğlu to Kadıköy. Technicians involved in loading that dataset have noted publicly that deduplication was only partially complete at launch, meaning a share of public-facing records duplicates restricted internal files — a compliance headache as well as an organisational one.

SALT Research, the archive and research centre based on Bankalar Caddesi in Karaköy, has handled its own deduplication separately from the municipal system. Its digitised collection — which spans late Ottoman commercial photography and early Republican-era urban surveys — runs to roughly 1.2 million items. Staff there have previously described deduplication as a prerequisite before any new batch upload, a workflow discipline that has kept their redundancy rate comparatively low. The contrast with city-scale repositories, where uploads arrive from dozens of departments simultaneously, is stark.

What Deduplication Actually Costs — and Who Pays

Commercial deduplication software licences for institutional use typically run between 8,000 and 25,000 euros annually at the scale Istanbul's bodies operate, based on published pricing from vendors active in European municipal markets. Manual review — still common in Turkish public institutions where procurement rules slow software adoption — is far more expensive in staff hours. A single archivist reviewing 1,000 image pairs for duplication takes roughly 40 working hours, according to benchmarks cited in a 2024 UNESCO report on heritage digitisation in Mediterranean cities.

The lira's sustained weakness adds a further layer of pain. Any software licence priced in euros or dollars has become significantly more expensive since 2023. A tool costing 15,000 euros in 2022 now demands the equivalent of roughly 560,000 lira at current exchange rates, compared to under 280,000 lira three years ago — a doubling in local-currency terms that has pushed some departments back toward manual workflows they had hoped to retire.

The practical path forward for Istanbul's institutions involves three steps that archivists and digital managers have repeatedly outlined at public events: completing the audit currently underway, establishing a single master repository with controlled upload permissions across Sultanahmet, Beyoğlu, and Kadıköy district offices, and standardising metadata at the point of capture rather than retrospectively. The İBB's cultural directorate is expected to present audit findings to the city council before the end of the third quarter. Until that report is public, the full cost of Istanbul's duplicate-image problem remains, like so many of the redundant files themselves, stored somewhere in the system — just not where anyone can easily find it.