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We have a digital Advent calendar again this year: #promvent24. This time, images and information about #zahlenausdembildarchiv (numbers from the image archive) can be found behind the windows of the #zahlenausallerwelt on the social media platforms Facebook, Instagram, Mastodon and LinkedIn.




Already during the project lifecycle of prometheus, two years after its launch, the association “prometheus – The distributed digital image archive for research and teaching e.V.” was founded in 2003 to consolidate what had been achieved in the project. In 2004, it then took over the legal succession of the project in order to ensure the financing and technical structure of prometheus and to further develop the image archive, including the learning elements. If you would like to participate in the association and actively contribute to promoting science and research through the development, provision and application of digital media in the field of art and cultural history, you are cordially invited to become a member.




There are currently 50,057 image collections in prometheus and 1,723 of these are public image collections, readable or writable. These image collections can be created and viewed by anyone with personal access. You can use them privately to collect images, share them with individuals or everyone else to pool your search results. You can also download them for further use in a research or teaching context.

(1) as a zip file for unpacking: in a folder you will then have the images and text files with the corresponding metadata for each individual image.

(2) as a PowerPoint file: a slide is created for each image including the metadata title, artist, date and location.

In addition, you can enrich your own and public image collections to create material collections. On the one hand, by adding a description of the topic of the image collection or keywords that can be clicked to search for other image collections on the topic. On the other hand, you can fill it up by adding literature references and web addresses, externally for content on the topic or internally for relevant image collections in the image archive. You can mention further information, suggestions for discussion and research questions in the comments.




The beginning of the semester seems like a good time to inform you about possible adjustments to your profile and settings. If you do not yet have a personal account with prometheus or no longer have one, you can register or extend your account and if you (then) have a personal account and are logged in, you can create and customize your profile.

Click on the name then on the pen and you can enter a new e-mail address or a new name, change your password or specify your research interests.
You can also change your institution or your license there by clicking on “Purchase a new license or change your institution …”.

After your change, your content such as image collections, your own database, favorites, etc. will continue to be available to you. If your personal access has expired, it may still be possible to reactivate it with all your personal settings. Please ask us before you have to create a new account and repeat your work in the image archive. We will be happy to help.




Programming interfaces – APIs – facilitate the transfer of data between systems. They are used in programming to create software or interact with an external system. Via API, developers have access to standard commands for executing general operations so that code does not have to be rewritten. Also prometheus offers an API, which enables communication with pandora, the software from prometheus, for your own new applications. The following actions are available
(1) Submit search queries,
(2) retrieve images and
(3) retrieve image collections.
Detailed information can be found under Documentation

Various museums also offer interfaces that make it possible to integrate their online collections directly into prometheus, for example the Amsterdam Rijksmuseum. So far, we have integrated seven image databases via API: Amsterdam Museum, Getty Museum, Metropolitan Museum of Art, Paris Musees, Rijksmuseum Collection, Statens Museum for Kunst and The Cleveland Museum of Art.

The Art Institute of Chicago also offers its public data via a centralized, searchable API. To show what is possible with their interface, they also provide a script that can be used to query the API for public domain artworks, which are then displayed with letters, numbers and special characters, as ASCII-Art.




Shibboleth (DFN-AAI) is a national browser-based infrastructure that was developed to provide a simple, transparent and secure process that can be used to shorten and streamline the authentication of people and the granting of authorizations. You only need to log in at one location (single sign-on), for example at your home university, and you can then access many different licensed services and online publications. It does not matter which device you use.
prometheus cannot yet be used via Shibboleth. The emphasis is on “not yet” because we are currently testing intensively with some institutions such as the University of Cologne. Here, logging in from outside already works for the test group:

Additional interested licensed institutions will be gradually integrated. If you are interested, please contact us.

… and further steps will be implemented in the next few weeks, for example the integration of your personal access with settings, personal data, image collections and image uploads, even if you change institutes.




The collaborative platform ARTigo, a long-term project of the Ludwig Maximilian University of Munich, brings together many game variants, all of which work in such a way that reproductions of works of art shown are to be tagged with keywords within a certain time in order to score as many points as possible as a player. After the games, these keywords are visible and saved as metadata for the images. This is intended to improve searches for works of art in image databases. In prometheus, the tags generated in this way are integrated into two image databases, one in DadaWeb from the Art History Institute of the University of Cologne and the other in ArteMIS, the original database of the Art History Institute of the Ludwig Maximilian University of Munich. As the following example shows, this metadata is also used to find “Bonaparte franchissant les Alpes au Grand-Saint-Bernard | Bonaparte crosses the Saint Bernard Pass” by Jacques Louis David…

…under the search term “Napoleon”.

For some searches, it may be useful not to search with the additional keywords. Therefore, in prometheus’ advanced search, it is possible to search across all fields and across all fields including the ARTigo tags.

For example, if you use “blue” as a search term, a search across all fields will display 28,950 records in the results list, and a search including the ARTigo tags will display 44,091 records.




Within the NFDI4Culture project, in the Task Area 3 “Research tools and data services“, the Flex Funds are available over four years to support projects and measures for the needs-based development or further development of research tools and data services in the NFDI4Culture communities.
In the first project year 2021, further developments were carried out by Task Area 3 staff, for example the image similarity search for prometheus.

In 2022, measures proposed for funding by the first Community Forum were funded, including the documentation and optimization of the open source graph database system ConedaKor.

After the second Community Forum, funding totaling €120,000 was approved in consultation with the Culture Steering Board, including the further development of the Graphical User Interface of the Corpus Vitrearum Medii Aevi and the further development of Kompakkt.

In 2024, a further ten measures were funded and applications for the fourth Community Forum “(Further) Development of Research Tools & Data Services“ are still possible until the end of August. The needs for tools, for the realization of which funds will again be available in 2025, will then be determined at the online meeting on 20 September from 9:00 a.m. to 1:00 p.m.




At prometheus you can use the simple search function to quickly and easily search for your search terms across all fields. In this one field, you have various options to narrow down or expand your search. For example, if you mark a search term with ~, the search will be “fuzzy”, i.e. words with a similar spelling will also be included in the search. If you enclose the search terms in quotation marks, the exact order of the conditions will be taken into account. You can also use the wildcards ? or * in your search.
The advanced search allows you to search in specific fields such as artist and title as well as search for combinations of different categories. A link is made here using the Boolean operators “and”, “or”, “and not”, for example “Raphael or Leonardo and not Madonna”.

Depending on your search query, it may also make sense for you to select image databases on a specific subject such as art, architectural history or archaeology and limit your search to these.

If you only want to search categories of databases, select all museum, institute or research databases.




As the 31st open access and 21st museum image database, the Getty Museum’s online collection with 196,526 data sets has been integrated into prometheus. since yesterday.

As early as in the first years of prometheus, the integration of this museum collection was a recurring topic at project meetings. When the publication of around 88,000 digital images of collection objects under the “Creative Commons Zero” (CC0) license made the rounds in March of this year, the plan was immediately up-to-date again and a new ticket was written.
Getty’s Open Content program was initiated over 10 years ago. The switch to releasing the entire public domain image collection under the CC0 license is the next step in improving transparency and access for everyone. This resource will be further expanded, including by acquiring additional works that will then be accessible to everyone for further use.

Short tip: If images are not displayed, they are not (yet?) under the CC0 license and can be viewed there and requested for further use after clicking on the original database (“house” icon in the left bar on the image).