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For Sherman and Craig (2003) Augmented Reality (AR) is a subcategory of Virtual Reality (VR). They define AR as “a type of virtual reality in which synthetic stimuli are registered with and superimposed on real-world objects”. AR is thereby “often used to make information otherwise imperceptible to human senses perceptible.” (29) This is mostly done through “special display technology [that] allows a user to perceive the real world with an overly of additional information” (28). Hence, AR “typically requires the use of a movable visual display” (30). In AR environments the users can “interact and also affect the remote environment by their actions.” (32) Thereby, AR intensifies a feeling of presentness.

Mehler-Bicher and Steiger (2014) clearly distinguish between AR and VR. In contrast to VR environments that attempt to create new (virtual) worlds, AR complements the existing world with additional computer-generated objects (9). They introduce the understanding that AR is an extension of human senses through features, which human beings usually cannot perceive (11). Referring to Azuma (1997), they emphasize three key elements of AR: the combination and partial overlap  of virtual reality and real environments, interaction in real-time and the spatial interrelation of virtual and real objects, which, however, in most cases of mobile AR devices cannot be fully realized (Mehler-Bicher/Steiger, 2014: 10). Two techniques are crucial for AR devices: tracking, the identification and tracing of objects, and rendering, the combination of real and virtual elements into a new scenery (11). This is usually done by the help of interactive digital surfaces that provide additional information when touched, the addition of virtual to existing objects based on pattern recognition and (re-)positioning through GPS- and geo-tracking (22).

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Physical sites play a crucial role in AR technology. Therefore, Manovich (2006) coined the term “augmented space” in order to describe "physical space overlaid with dynamically changing information.” (220) In doing so, the augmented space becomes multidimensional (223). Furthermore, augmentation “combine[s] different spaces together.” (226)

Accordingly, for Manovich, augmentation is a “cultural and aesthetic practice” (220) that turns physical space into a “data-space” (222). He defines AR as “the laying of dynamic and context-specific information over the visual field of the user” (222). Although limiting augmentation to the visual dimension, Manovich adds two important aspects to the previous definitions. Augmented information stays dynamic and it is related to a particular spatio-temporal context by adding “information that is directly related to the user’s immediate physical space.” (225).

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AR technology can also be used for presenting virtual objects in museum or exhibition spaces, or for adding additional information to existing artifacts (Mehler-Bicher/Steiger, 2014: 18). Thereby, AR technology becomes especially interesting within the fields of historical research and education as well as memory and heritage studies.

Kevin Kee and Timothy Compeau (2019) discuss the potential of AR for seeing, studying, understanding and sharing history in compelling new ways (2). They emphasize that compared to historians, especially museums and heritage professionals have been receptive to the potentials of digital techniques and devices to engage with the past:

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“Many have explored how mobile phones equipped with audiovisual capabilities can facilitate place-based learning and enrich exhibits with expanded information, varied sensory experiences , and interactivity.” (Kee, Poitras, Compeau, 2019: 207). 

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“Many have explored how mobile phones equipped with audiovisual capabilities can facilitate place-based learning and enrich exhibits with expanded information, varied sensory experiences , and interactivity.” (Kee, Poitras, Compeau, 2019: 207). 

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Connecting to History through Augmented Realty

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Connecting to History through Augmented Realty

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The US Holocaust Memorial Museum has introduced a mobile augmented reality application, which allows visitors to access additional information by using mobile devices in a museum exhibit, and identify people depicted in private family photographs from the pre-Holocaust period.

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Connecting to History through Augmented Reality

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Kee, Poitras, Compeau (2019) especially focus on the technique of contextualization, which “allows users to imagine themselves within the original context of the artifact, place, or event.” (208). This would challenge dominant interpretations and enable new forms of exploring historical sites and landscapes (210).

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Virtual reality app recreates horror of Germany concentration camp

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The Bergen-Belsen Memorial uses a combination of AR and VR technology in order to expand the experience of the site. Mobile devices allow access to a virtual model of the destroyed camp. With the help of a tablet, this model can be projected over the actual site. The model is not an authentic reconstruction as the camp had looked like when it was still in operation. The memorial had opted for a sober and abstract reconstruction that recalls architectural models or sketches. In addition, users will also get other information by accessing testimonies or relating historical photographs to the present site.

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A flight through a recontruction of the Bergen-Belsen concentration camp (v.2012)

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Geographical tracking makes it possible to connect two disparate worlds in the sense of Manovich (2006), the present reality at a historical atrocity site often characterized by invisible traces and augmented information, digital data and virtual reconstructions that sense the historical setting or events. This is rendered into an AR experience that establishes a state of traceable co-presence of past and present.
The Dachau Memorial uses this technology in order to enable visitors to access historical photographs from the days of the camp's liberation in 1945 at the actual  places where they were taken. With the help of a mobile phone or tablet, users can superimpose the actual memorial site with black and whit photographs. By moving the device they can also further explore the historical images. In addition, they listen to testimonies from survivors, liberators and others who witnessed the liberation of the camp, and get additional information.

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Die Befreiung AR | Augmented Reality App | Projektfilm | BR

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The "Visual History of the Holocaust" Media Management and Search Infrastructure (www.vhh-project.eu) will also make use of location-based services that allow for displaying digital assets (in particular films, photographs) as well as their annotations and relations based on the current position of the user. With the user moving through space, also the available digital information changes.
With the help of maps and the Timeline, physical places and things may be located that have been captured on film or in photographs. Their visual depiction may be compared to their current appearance. New photos may be taken and combined with the historical images. Observations and experiences may be commented and sound recordings combined with the historical footage and photographs.
This is particularly relevant for memorial sites, however even more so it may be relevant for places where no memorial and not even a sign tells that this has been a site of Nazi atrocities. It augments existing and non-existing physical traces with digital information, links tangible and non-tangible objects, expands the present space trough a virtual space and through additional layers of time.
(Information taken from: https://www.vhh-project.eu/wp-content/uploads/VHH_Publication_D3-1_Definition-of-Engagement_v1-6_2019-12-31.pdf)

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AR responded to “a new paradigm, one in which physical space is augmented with electronic and visual information.” Kee, Poitras, Compeau (2019) assert that “[i]nstead of putting people in an artificial world, we can now augment the physical world by embedding it with digital data, networking, communication abilities, and enhanced properties.” (209). Accordingly, Kee and Compeau in their introduction enthusiastically state that AR technology can:

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AR technology can provide on-the-spot supplementary information in museums or at historical sites that enable telling hidden stories and offer lesser-known facts and information in order to enhance the knowledge of the visitor/user. By the help of three-dimensional reconstructions or visual digital documents it is possible to demonstrate how an object or place changed over time. Guiding visitors at historical sites with the help of AR technology and providing location-specific data, increases the sensory engagement with a place.

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AR technology can provide on-the-spot supplementary information in museums or at historical sites that enable telling hidden stories and offer lesser-known facts and information in order to enhance the knowledge of the visitor/user. By the help of three-dimensional reconstructions or visual digital documents it is possible to demonstrate how an object or place changed over time. Guiding visitors at historical sites with the help of AR technology and providing location-specific data, increases the sensory engagement with a place.

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In order to realize this potential, Kee, Poitras and Compeau (2019) suggest combining AR with “playful exercises to promote the inculcation of historical thinking skills.” Thereby, they intent to “deepen users’ connection with, and understanding of, the past.” (208) This is a particularly site specific aspect of AR that would help better understanding the impact of a physical environment and a specific topography in the course of history. Furthermore, this would enable new forms of digitally annotating landscapes beyond placing inscriptions, plaques or erecting monuments.

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Craig, A. B. and Sherman, W. R. (2003). Understanding Virtual Realty. Amsterdam: Morgan Kaufman Publ.
Kee, K., & Compeau, T. J. (2019). “Introduction: Seeing the Past.” In: Kee, K., & Compeau, T. J. (eds). Seeing the Past with Computers: Experiments with Augmented Reality and Computer Vision for History. Ann Arbor: University of Michigan Press, 1-10.

Kee, K., Poitras, E., Compeau, T. (2019). “History All Around Us: Toward Best Practices for Augmented Reality for History.” In: Kee, K., & Compeau, T. J. (eds), Seeing the Past with Computers: Experiments with Augmented Reality and Computer Vision for History. Ann Arbor: University of Michigan Press, 207-223.

Manovich, L. (2006) “The poetics of augmented space,” Visual Communication 5:2, 219-240.
Mehler-Bicher, A., & Steiger, L. (2014). Augmented Reality: Theorie und Praxis. Berlin: de Gruyter.