Media Facades: Fundamental terms and concepts

Author: Dr. Gernot Tscherteu
Research: DI Wolfgang Leeb

Media facades create utterly new connections between digital space on the one hand and architecture and urban space on the other hand. Never before was there an interface between the physical and the digital world, which was public to such an extent, that it appeals not only to individual users, as in the case of a personal computer, but also to whole groups or even to a whole urban population and that furthermore also allows to “reply”, i.e. to interact with a facade or to design its content. In this case, a powerful potential for design and effectivity is created, involving a range of chances and risks that are difficult to estimate and that require thorough discussion. The producers and the users of media facades equally face a range of challenges, and it will need time for fully differentiated opinions and positions to evolve from the discourse which is just taking shape. This exhibition has been conceived in a way that it supports this essential discourse by collecting relevant projects, looking behind the “facades”, and by making apparent their materiality and technical structure. Certainly a more refined technical understanding will be helpful for developing a more differentiated attitude to media facades. One of the purposes of the following introductory text is to demonstrate the range of technical characteristics that have a substantial influence on the visual experience, but also on the interactivity and the “urban value” of media architecture. Media facades elude a classification into mutually exclusive categories and therefore it is more meaningful to discuss their most important characteristics (display technology, translucency, interaction, …) and to demonstrate that the individual projects presented in the exhibition base themselves on quite similar elements of design, but interpret these very differently and thus vary from each other. Thus, in the diagram below, a media facade will not only be classified concerning only one element, but it will take a place in relation to every single one of these characteristics. The so-called media facades are simply good examples for the relevant characteristic, but naturally they also exhibit other characteristics and would eventually also serve as good examples in those places. It is not the point to rigidly classify media facades and media architecture, but to have a set of terms at hand in order to be in a better position to compare and discuss them. Earlier attempts of classification and disambiguation that have partly found their way into my work are not to remain unmentioned and are cited in the sources.

Click on image to get a bigger clickable mind map:

Display technology

The handling of light serves as the best starting point for technological consideration: Does the facade actively emit light, or does it create images through mechanical movement at the surface of the building? Kinetic and even static media facades obviously also work with light – albeit in a passive way. They use sunlight or ambient light and modulate it in order to create surface effects and image information. Examples for this are the projects Flare or Daisyworld. There is a range of technologies for the production of light on media facades (LED, fluorescence, …), and likewise there are different methods to move mechanic parts: from compressed air, to servodrives or the simple use of wind energy. A special case is demonstrated by projected facades): the do not generate light by themselves. The surface of the building is used as projected area and the projection occurs from the outside onto the building surface, or alternatively from the inside onto translucent areas (windows in most cases), which are thereby converted to screens. In this exhibition we have disregarded projected facades – mainly because our topic is the smooth integration of the display into the architecture and this embraces projections only in exceptional cases. Of course this point of view is subjective and vulnerable.

Image properties

What are the properties of the image created by the media facade?

Resolution: Of how many pixels is the image composed? The spectrum is enormous – some examples: Blinkenlights 144 pixels, UNIQA about 160.000, Grand Lisboa over 1 Million pixels. A larger number of pixels does not necessarily improve the quality of the image – Blinkenlights shows how much is possible with very few pixels – but definitely a higher resolution allows for sharper and more detailed pictures, if needed. Pixel pitch: How big are the pixels and how far are they located apart from each other, taken from their center.

Diffusion: The size of the individual pixels has a big effect on the observer. It is possible to turn light sources as small as a couple of millimetres (like LEDs) into pixels of the size of one meter through the use of diffusion surface – as in the case of Galleria Store in Seoul. The luminosity or light power of a lamp is dispersed into a larger area through the diffusion, but its luminance or light density is thereby reduced.

Distance from the observer: There is a direct relation between this property and those of pixel pitch and diffusion, because the bigger the pixel pitch or the pixels, the farther away one has to be from the picture in order not only to see single dots, but to recognize a meaningful overall picture. Viewed from up close, interesting abstract light effects may result from this fact.

Brightness: The techniques mentioned under the point „Display technology” are highly variable in respect to brightness. Of all the active displays, only LED is bright enough to persist in direct sunlight. However, some kinetic facades (like Flare) skilfully take advantage of the sunlight. During the night, too much brightness may turn into a drawback, since it affects residents and traffic.

Colour depth / Tone: Depending on the technology, more or less colours are at one’s disposal. Reduction to fewer colours (like in the case of BIX, SPOTS, Blinkenlights or Chanel in Tokyo) may also be used as stylistic device. LED allows for a production of colour spaces with millions of colours. Integration of the display into the building

Integration is a vital point for the assessment of media facades – a decisive characteristic („differentia specifica”) for the acknowledgement of something as media facade or not. Without integration, the display seems fitted and constitutes its own level of meaning, which seems detached from the building. If a display has been integrated well into the building or its facade, then these two merge into something new – what we refer to as media architecture. In addition to the constructive integration, the content may also be customized with respect to the building and emphasize the unity of display and building. Since the integration of building and display is not simply a superficial characteristic that is restricted to the facade, I here find the term media architecture more suitable and more comprehensive. The following speaks in favor of the term media architecture: The media concept can not only include the facade, but also the room lighting and thereby reaches from the surface into the depths of the building. Spatial and medial structures overlap, so that communicative processes may evolve, which may not only occur on the surface of the building, but also inside, in the public sphere around the building and finally also – spatially unrestricted – in electronic media. The term “architecture” makes advances to this, since it is also open to non-spatial structures and processes – and exactly that is what many of the successful projects are about. In some cases, successful integration may also be accomplished when the building has already been constructed and the media facade is designed and installed only afterwards (UNIQA is a good example for this). As a general rule, successful media architectures emerge especially when all factors that have been regarded here are considered already in planning and are interwoven to a coherent concept. The relationship of the terms “media facade” and “media architecture” is not substantially different from the relationship of “facade” to “architecture”. Facade refers to surface and all of the functions that are part of a surface: protection, climatisation, representation, and so on. Architecture on the other hand is a substantially wider term and refers to the whole range and depth of spatial structures and functions. Moreover, this term is often used also in reference to non-spatial structures – see for example “software architecture”.

Permanent / temporary

Closely connected to the issue of integration is the question of the durability of a media facade installation. One should generally suppose that permanent installations should yield better results, because more planning and money is spent on these. In practice there are many exceptions to this assumption: the most convincing being Blinkenlights, and also many show facades of concerts and events are quite successful (Asian Games, for example). In this context, successful installations with artistic content (like SPOTS) are also not to be forgotten.

Dimensionality

Another aspect of “integration” is dimensionality. Since buildings usually are spacious and not simply flat structures, obviously media facades should also have a spatial effect. Only in uncommon and extraordinary cases will it be possible and meaningful for a display to take up the entire three-dimensional space of a building, since this could easily lead to problems with the occupants. There are already many concepts that include the room lighting of a building into the projection. As long as there are no occupants in the house, projection into the depth of the building is thus possible – but it is temporally restricted to a couple days every year and a few hours every day. More common, so far, are “2.5 D” projections. 2,5 D means that media facades are not restricted to only one surface, but flow around edges of buildings (Galleria) , or extend to spherical surfaces (UNIQA and Grand Lisboa). In this way, all-around-projections and striking spatial effects are possible. A good example for a true three-dimensional display is the Nova installation inside the train station in Zürich.

Transmitted light / Phantom view (Transparency / Translucency)

There are various points in which media facades may come into conflict with other functions of the building. The most important ones concern light and energy (for energy see below, sustainability). With respect to light the issue at stake is that components of a media facade cover parts of the surface of the building. Sometimes there is not enough daylight reaching into the inside of the building, sometimes there is none at all, and so the use of the subjacent space as office space is no longer possible. For this reason, various approaches have been taken to reduce the light-emitting parts and to maximize their luminosity. The properties of LEDs serve these goals well and thus they are increasingly integrated into facade components like cover caps and louvers for sun protection so that they subduct only a small amount of daylight. In other cases, occupants are completely unimpaired by the media facade. There certainly is a logical conflict between the performance of transmitted light and the resolution or the pixel pitch also in those cases, where the lighting socket is integrated into the facade. In order to attain higher resolution or to reduce pixel pitch between rows of pixels, the facade grid has to be adjusted accordingly, or alternatively louvers for sun protection or similar components need to be placed in front of the facade, which necessarily impairs the performance of daylight. Satisfying solutions are especially achieved through the use of forward-spaced components with integrated lighting sockets, which equally feature a high quality image and high quality usage. From the point of view of the occupant, it is not only important for him to receive enough daylight, but also that he enjoys an unobstructed view. A facade may be translucent, but not transparent, as in the case of the Chanel building in Tokyo, where building film was used as diffusion layer. Obviously, one of the designer’s goals in this case was to dissolve the individual lighting sockets into lighting areas using Privalite-glass, and to thereby create image effects that strongly resemble fabric. The magnificent effect of the image in this case really is at the cost of the occupants, who cannot clearly see outside during operation. The diffusion layer furthermore has the effect that part of the light is reflected inside the building as scattered light. Therefore, a blind is lowered as soon as the display operates. This contributes to the further impairment of the room’s quality. Blinds are also used in order to screen the room lighting from the outside, i.e. to separate those two levels of light – inside and on the media facade.

Energy consumption – sustainability

In time of increasing energy consumption, which not only leads to high costs but also to conflicts evolving around distribution, one cannot keep quiet about the fact that media facades consume energy – quite much in some cases. The consumption depends on the effectiveness of the illuminants, as well as on their number and luminosity. LEDs are very effective, but if they are used in high numbers (in some projects way beyond one million units), then their consumption levels accumulate or square. The brighter, the bigger the total area and the more densely packed the pixels are, the higher is the energy consumption. Acute cases involve competing with sunlight and operating displays during the day and under direct sunlight. We will not have to wait long for discussion to come up about the meaningfulness of such projections. Here, as in other cases, one will have to compare costs and benefit, and relevant in this case has to be what is justifiable to society, not simply what a big company can afford. Since the issue of energy seems to essentially involve problems of distribution, one can not categorically speak of what is justifiable and what is not. If enough energy is available on the spot, for example due to the utilization of sun power, argumentation will be facilitated, as in the case of Greenpix. Furthermore, one should clearly keep in mind that besides the operation, other phases of the lifecycle of a display also have to be included in an ecological balance sheet, like its production and disposal.

Media content and the building

This concerns the issue whether or not the projection of a facade takes into account the building as spatial structure or the local environment. This is another case which is closely related to the integration of the display into the building. Even if a smooth integration has been accomplished, the projection still may not establish a relation to the building. In my opinion, one can not speak of a relation even if the logo or the products of the building’s proprietor are included in the projection. Such a relation in terms of content make sense in some cases, but it should not only regard the corporate identity of the company, but also take into account the shape of the building. In a successful master plan, all three components – identity, architecture and projection – should be balanced and considered in advance. It doesn’t seem purposeful to me, if media facades refer to content that is in no relation to the building, its occupants and the place where it is located – a case often found in poor advertisements. If, on the other hand, the above mentioned components are equally balanced, not only successful media architecture may arise, but also a strong advertising effect. In the process of design and evaluation of advertisement on buildings, it is often forgotten that the value is not only to be judged by the number of people witnessing the projection, but also by how it affects the people’s perception of the building. Often there is more benefit for the proprietor, if attention is successfully drawn to balanced media architecture, as in the case of the UNIQA-building, than in cases of a permanent projection of his logo. The building thereby turns into a landmark, a part of everyday urban perception that one gets accustomed to and after some time does not want to miss. The benefit that a proprietor (or renter) may derived from a media facade consists less in short-term advertising effects and more in long-term relationships and identifications that may arise between pedestrians and the projected building. This value is not as easily quantifiable as that of advertising spots, but it is still there and highly estimated. Certainly every form of projection of media facades – be it for advertising purposes or a purely artistic projection – requires a lot of expertise and experience, because, as we have seen above, they differ so much from ordinary screen effects in many respects (like resolution, pixel pitch and brightness) and require much sensitivity for architecture and urban space.

Interaction

By far the biggest potential for the identification of occupants with media architecture consists in an interactive media concept. The projection of Blinkenlights in Berlin, for example, is well documented. Here, the “users” were given different possibilities to communicate with the building itself, or with other inhabitants of Berlin. On the one hand, clips containing simple animations or text messages of the user could be sent to the façade – love messages were very popular in this case. On the other hand, one could even play “Pong” via cell phone interfaces. During “normal operation”, Blinkenlights automatically performed a predefined playlist of user-generated animations. One could discontinue the programme via cellphone, in order to play Pong either alone or together, or to activate a previously uploaded love letter. Rendering could be temporally timed through the submission of an activation key via cell phone, so that the message would perfectly suit a romantic moment with one’s loved one. It is obvious that through very personal moments like these, where one self plays the leading part on the media facade, a particular intense form of identification is established. These are unique experiences, which stay in one’s memory and are closely associated with a particular place. What more could a proprietor expect, than for the residents and visitors of a city to feel personally connected to his building? The website and public access to the software played an important part in the formation of a community around Blinkenlights. The users conceived of themselves as part of the medium and had tools at their disposal, with which they could create concrete and meaningful messages. They turned into active designers of media content and thus accepted Blinkenlights as THEIR medium.

Outlook

The enormous development of consumer generated media in Web 2.0, and within that the boom of social networks like Myspace and Facebook, allows for the assumption that there is an enormous potential for applications which create social networks around media architecture, and which thereby will lead to further penetration of physical and virtual space. Here, new media formats will be created, which will presuppose a high level of interdisciplinarity on the part of the designers and which have the possibility of producing very innovative urban experiences.

Certainly the projects of this exhibition can not be sufficiently described with the characteristics presented above. Especially the social and urban aspects of media architecture need further engagement and defy an all too technical description. We are aware that much work needs to be done in this domain. Possibly an exhibition may not even be as appropriate a format as a broadly based discourse of protagonists and experts and so we hope that the establishment of this discourse on a broad basis will be successful and that this exhibition has nevertheless provided qualified illustrative material and solid basic knowledge for this purpose.

Gernot Tscherteu, Mediaarchitecture.org
Director of the exhibition

Sources:

Alexander Wahl, Wandelbare (mediale)
Gebäudefassaden, 20.01.2002, 2008;
http://www.alexanderwahl.de/dateien/medienfassaden/medienfassaden.html
zuletzt geprüft: 5. Oktober 2008

Susanne Jaschko / Joachim Sauter, Mediale
Oberflächen – Mediatektur als integraler Bestandteil von Architektur und Identität stiftende Maßnahme im urbanen Raum, ublished in Arch+, Nr 180, Convertible City, Sept 2006, official exhibition catalogue of the German Pavillion at the 10th Bienale of Architecture in Venice, Italy.
http://www.sujaschko.de/downloads/256/Mediatektur
zuletzt geprüft: 5. Oktober 2008

Joachim Sauter, Das vierte Format: Die Fassade
als medialeHaut der Architektur; 2004,
http://netzspannung.org/cat/servlet/CatServlet/$files/273668/sauter.pdf,
zuletzt geprüft: 5. Oktober 2008

Andy Jörder, Improve Your City’s Appearance – Medienfassaden in urbanen Brennpunkten Diplomarbeit.
http://www.nd80.de/portfolio/pdf/IYCA_Screen.pdf,
zuletzt geprüft: 5. Oktober 2008

Ava Fatah Gen. Schieck, Media Screens – Urban Environments as a Medium of Communication, Mediamatic May 2007,
http://www.slideshare.net/revi.kornmann/media-screens/
zuletzt geprüft: 5. Oktober 2008.

Lucy Bullivant, 4dsocial: Interactive Design Environments, Wiley 2007

Lucy Bullivant, Responsive Environments:
Architecture, Art and Design, Victoria & Albert Museum 2006

Ag4, ag4-mediafacades, Daab 2006

Medienarchitektur, Arch+ 149 150,

http:www.Mediaarchitecture.org