On November 1, 2018, the Municipal Archives announced that the long-awaited project to digitize the 1940 ‘tax’ photograph collection was complete and all of the 720,000 images now are online in the agency’s photo gallery.

It required more than thirty years, many thousands of dollars and hours of labor, plus two cross-country trips. But we think it’s fair to say that the tax photographs have now reached their full potential as one of the most important research resources in the Municipal Archives.

The digitization project is only the latest chapter in the story of the 1940 tax photographs. The Archives accessioned the collection from the Department of Finance in 1980. At that time it consisted of 2,047 strips of 35-mm black-and-white nitrate negative film (36 frames per strip), each stored in its original metal canister. The canisters were transferred from the Municipal Records Center; it is not known how long they had been in storage. Despite the less-than-ideal environment at the Center, the negatives were in relatively good condition, suffering only minor shrinkage due to age. Some films were scratched and others exhibited evidence of redox (reduction-oxidation) blemishes, but they did not break when unrolled.

The value of the collection was immediately apparent to City archivists. Given their fragile condition, it was not possible to allow patrons to examine the original negatives, but they could request prints. To remedy this limitation, the archivists developed a preservation and access plan that took advantage of 1980s technology and equipment to duplicate fragile motion-picture films.

It would have been cost prohibitive for the Archives to acquire the necessary equipment and in 1988 the decision was made to contract-out the duplication work. To fund the $332,000 budget (about $560,000 in 2018 dollars), grant applications were submitted to public agencies and private foundations. Over several years, the Archives assembled the necessary funding from the National Historical Publications and Records Commission-$50,000; the Andy Warhol Foundation for the Visual Arts-$25,000; the New York State Library-$25,000; the Municipal Archives Reference and Research Fund-$92,346; and the National Endowment for the Humanities-$138,259.

With funding in place, the nitrate negatives made their first journey across the country to the vendor, Western Cine, of Denver, Colorado. The vendor spliced together the negative strips to make 1,000 ft. rolls. Using a liquid-gate printer designed to duplicate nitrate motion-picture film they created a new positive image on fine-grain polyester stock. From this master they produced a second-generation negative and another positive copy. The second positive was cut down to 100 ft. lengths and used to produce another copy on diazo stock—a microfilm product—to serve as the reference copy for use in a microfilm-reader machine.

For that time, this was a good solution. But there were drawbacks—the new negative was second generation meaning that much of the fine detail in the original negative did not reproduce. The reference diazo was third generation and it was difficult to view the pictures in a microfilm machine.

By the 2000s, the “new” printing negative was beginning to deteriorate and using the microfilm for research was a daily struggle for patrons and staff. There had to be a better way. And there was—digitization.

It would take several more years of research and planning, but by 2015 City archivists determined that decreased scanning costs and improved technology made it possible to consider digitizing from the original 1940s nitrate negatives. Once again, it proved more cost effective to contract-out the digitization service.

During the time it took to procure the vendor contract, project staff began preparing the metadata—the information about the images that is required to make the collection searchable. It was a big job. There had been so many changes in the City since the 1940s—new highways, housing developments, airports, etc.—that the available 1980s block and lot database had only limited usefulness. Project staff consulted period-appropriate land atlases and, after a year of careful research, they created a database that can be searched by either address or block and lot number.

Once the $200,000 contract with the selected vendor was signed in 2017, the project team began to prepare the original negatives for another cross-country trip to the digitization vendor, Luna Imaging, in Los Angeles California. (These negatives had been stored in freezers since their return from Denver in 1990.) After carefully defrosting them, the negatives were packed into special fire-proof shipping canisters. And, over one long weekend a company specializing in hazardous materials drove the canisters, non-stop, to California.

Luna Imaging used an overhead copy stand with a Canon 5DS camera and light box attached, to capture the images at a 24-bit RGB. Luna then converted the RAW files to TIFF format, and named each file with the borough, block, and lot numbers. Multiple pictures of the same block and lot were given a letter designation (a, b, c, etc.) as a suffix to the file name. If the identifying block or lot number sign did not appear in the image, the file was named with an alphanumeric code and the image number from the original roll.

When the new digital files were received by the Archives, the project team began their quality-inspection protocol. Visually inspected each image, they compared the file names to the block and lots signs, checking the embedded metadata fields, and ensuring that properties such as file size, bit-depth, dimensions, and resolution met specifications.

When the quality inspection was completed the metadata and images were uploaded to the Archives digital gallery. From start to finish this process took approximately 2 years to complete. The collection is amazing and we are hopeful that it will not require another cross-country trip.