Istanbul's Duplicate Image Problem: The Key Decisions That Will Define the City's Digital Heritage Archive

Istanbul's municipal digital archive is at a crossroads. Years of digitisation drives across the city's major repositories — from the Istanbul Metropolitan Municipality's records office in Saraçhane to the Atatürk Library in Beyoğlu — have produced a sprawling database riddled with duplicate image files, some replicated dozens of times over, consuming server capacity and degrading the quality of public search results. The problem is now forcing a set of concrete decisions that administrators can no longer defer.

The timing matters. Turkey's broader push to digitise cultural heritage accelerated sharply after the February 2023 Kahramanmaraş earthquakes, which destroyed irreplaceable physical records across the southeast and forced a national reckoning with how fragile analogue collections really are. Istanbul, holding the bulk of the Ottoman imperial archive and centuries of municipal cartography, was never going to be spared that conversation. Officials at institutions including SALT Research in Karaköy, which maintains one of the city's most-used open-access image libraries, have spent the past two years uploading at pace — sometimes, critics note, at the expense of cataloguing rigour.

What the Duplication Problem Actually Looks Like

The mechanics are straightforward but the consequences are not. When scanning teams from different departments digitise the same physical photograph or map — say, a late nineteenth-century Bosphorus shoreline survey held in both the Istanbul Büyükşehir Belediyesi archive and a partnering university collection — the resulting files often enter the same shared cloud infrastructure without cross-referencing checks. According to documentation circulated within the Istanbul Metropolitan Municipality's information technology directorate in March 2026, redundant image files were occupying an estimated 34 percent of the archive's active storage allocation. That figure, if accurate, represents a significant drag on a system already under pressure from rising cloud storage costs at a time when the Turkish lira's continued weakness makes dollar-denominated server contracts expensive to maintain.

The Atatürk Library on Yusuf Kemâl Tengirşenk Sokak in Beyoğlu holds roughly 1.4 million catalogued items, a portion of which have been digitised through a rolling programme that began in 2019. Staff there have been trialling deduplication software since early 2026, but the process is complicated by the fact that two scans of the same object are rarely pixel-identical — lighting differences, scanner calibration, and file format choices mean automated tools flag genuine variants as well as true duplicates, requiring human review that the current staffing level struggles to sustain.

The Decisions Ahead — and Who Makes Them

Three choices will determine how this unfolds over the next twelve months. First, the municipality must decide whether to adopt a centralised deduplication protocol that all partner institutions — including universities, private foundations like SALT, and district-level libraries — are required to follow before uploading new material. That would require a memorandum of cooperation that does not yet exist, and negotiations with institutions that guard their cataloguing autonomy jealously.

Second, there is the question of which files to delete when duplicates are confirmed. Archivists argue that even near-identical scans can carry distinct metadata value — a 1960s photograph of Galata Bridge scanned in 2015 and again in 2024 may reflect improvements in resolution technology that make the newer file worth keeping without simply erasing the older one. A hybrid approach, retaining a master file and flagging alternates as subordinate versions rather than deleting them outright, is gaining support among professionals at institutions such as the Istanbul Research Institute on İstiklal Caddesi.

Third is funding. The municipality's 2026 technology budget, under pressure from broader fiscal constraints tied to inflation running well above 40 percent annually in recent periods, has not ring-fenced a dedicated allocation for archival data management. Without that, any protocol agreed on paper risks stalling in practice.

The next formal review is scheduled for September 2026, when the Istanbul Metropolitan Municipality's digital transformation committee is expected to present options to senior management. Heritage professionals watching the process say the September meeting is the realistic last window to set standards before the next major scanning campaign — covering Fatih district's neighbourhood records — begins in late autumn. Miss that window, and the duplicate backlog will simply grow larger.