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Ясмин КАТХЁФЕР / Jasmin KATHOFER
| Не «что такое индекс?», а «индекс - он какой»? О различении фотографических индексальностей / Not what, but HOW is the Index? On the Differentiation of the various Indexicalities of Photography |
Ясмин КАТХЁФЕР / Jasmin KATHOFER
Университет искусств Брауншвайга, Германия Ассистент директора Института исследований медиа
Braunschweig University of Art, Germany Assistant to the Director of the Institute and Coordination, Institute of Media Studies
НЕ «ЧТО ТАКОЕ ИНДЕКС?», А «ИНДЕКС - ОН КАКОЙ»? О РАЗЛИЧЕНИИ ФОТОГРАФИЧЕСКИХ ИНДЕКСАЛЬНОСТЕЙ
Аналоговая фотография индексальна, цифровая - тоже, только по-другому. Кроме того, аналоговые фотографии различаются между собой, точно так же, как различаются между собой и цифровые фотографии. Для индексальности фотографии, тем не менее, важно в первую очередь не то, аналоговое перед нами изображение или цифровое: важно само конечное изображение. Но если обратить внимание на разные способы получения фотографических «следов», то можно заметить, что их индексальность - разная, и что категорий здесь больше двух.
Данная статья исследует то, в каких пределах разные манифестации индексальности существуют в разных формах фотографических записей. В тексте рассматриваются аналоговые методы фотографической регистрации - такие как печать позитива с негатива и прямая позитивная печать, гумми-бихроматная печать и Полароид - а также цифровые способы фотографической регистрации. В статье утверждается, что разные способы регистрации порождают разные виды материальности, что приводит к вопросу о том, насколько материальность необходима изображению для того, чтобы считаться фотографией и, далее, что необходимо для того, чтобы утверждать, что мы имеем дело с индексальностью. Если короче: вопрос «что такое индекс» необходимо заменить вопросом - задаваемым по отношению к разным фотографическим техникам - «индекс - он какой?».
Ключевые слова: индекс, фотографические техники, цифровая фотография, теория медиа.
NOT WHAT, BUT HOW IS THE INDEX? ON THE DIFFERENTIATION OF THE VARIOUS INDEXICALITIES OF PHOTOGRAPHY
An analogue photography is indexical, a digital photography is too - just different. And analogue photos are not just as any other analogue photos, so as there are different types of digital photographs. For the indexicality of photography, however, it is not so im- n portant whether the photo is analogue or digital - in most cases only the final image is of actual interest. But if one looks at the different forms of acquisition of 'photographic traces', one notices that the way how they are indexical differs and that they can be divided into more than two categories.
This text will deal with the question of the extent to which different manifestations of the index occur in different forms of photographic recording. The text will look at analogue recording methods, such as negative/positive printing methods, direct positive printing methods, Gum bichromate and Polaroid, as well as digital recordings. It is to be shown that different recordings also result in different materiality, which ultimately also includes the question of how much materiality is required for a photo to become a photography and, eventually, what is needed for an index to be an index. Or in a nutshell: It should no longer simply be asked what an index is, but - with regard to various photographic techniques - what is the index like?
Key words: index, photographic techniques, digital photography, media theory.
| 4 (37) 2019 |
Ясмин КАТХЁФЕР / Jasmin KATHOFER
| Не «что такое индекс?», а «индекс - он какой»? О различении фотографических индексальностей / Not what, but HOW is the Index? On the Differentiation of the various Indexicalities of Photography |
II
f you deal with indexicality - and then -on top of that with photographic indexicality - somebody always comes along and asks: And what do you think about digital photographs? Do you think they are indexical? And every time I am asked this question, I say: Yes! The question I ask myself, however, is why does everybody think that digital photography no longer has a connection to, the real'? In this article I would like to explore this question, but also to put forward the thesis that the differentiation between analog and digital is not the decisive one. Rather, it seems that it would be more appropriate to ask what kind of indexicality, or better, indexicalities of photography, exist.
The aim will be to detach the consideration of the index from the notion that it can be equated with analog photography, while "the digital is to be radically separated from the indexical, and finally the indexical per se is to be reconciled with a claim to truth or with an image realism"12. Rather, a differentiated view is to be taken of how the index can be described in photographic terms.
In order to pursue this question, I will look at the various technical inscriptions of a photograph and thus of the index. Before doing so, I would like to go into the concept of indexicality and outline the transition from the photographic to the post-photographic era in order to then outline the status of the photographic indexicality in the after-post-photographic age.
1 Note: all quotations are translated from German to English.
2 Martin Doll, „Entzweite Zweiheit? Zur Indexikalität
des Digitalen," in Segeberg, Harro (ed.) Film im Zeit-
alter Neuer Medien II. Digitalität und Kino (Pader-
born: Fink 2012), pp. 57-86, here p. 57.
1. Indextheorie - long story short
According to Charles Sanders Peirce, a distinction can be made between three character forms: "First, there are similes or icons that convey the ideas of the things they represent simply by imitating them. Second, there are indicators or indices that show something about things because they are physically connected to them. Of this kind is a signpost indicating the path to take, or the relative pronoun placed directly after the name of the thing to name, or an exclamation in the vocative like 'hello! you there', which acts on the nerves of the person addressed and forces their attention. Thirdly, there are symbols or general signs that have been linked to their meanings 12 through their use. They include most words, idioms, speeches, books and libraries. [...]"3
For many years, (analog) photography in particular has served as a popular example of a medium that produces an index, because photographs are created "under such circumstances that they were physically forced to correspond point by point to nature."4 In the case of photography, this is justified by the light that falls onto the image carrier from the photographed object and inscribes itself on it as an indexical trace. Photographs are thus indices, but at the same time they can also be read as icons - whenever someone asks about the similarity of the subject with the object - or "more specifically: to ask oneself how the configuration of grey tones or colours is represented on the image surface according to relevant image codes, i.e. what kind of image it is, e.g. a
3 Charles Sanders Peirce, Semiotische Schriften (Frankfurt/Main: Suhrkamp, 2000), p. 193.
4 Ibid.
| 4 (37) 2019 |
Ясмин КАТХЁФЕР / Jasmin KATHOFER
| Не «что такое индекс?», а «индекс - он какой»? О различении фотографических индексальностей / Not what, but HOW is the Index? On the Differentiation of the various Indexicalities of Photography |
man - with-determined-looks-image."5 S0ren Kj0rup describes this reading as the common reading of a photograph, which is absolutely plausible, because when a photograph is examined, the viewer first tries to determine what he recognizes in the photograph. If one tries to approach the index - or in other words: to read a photograph in-dexically - the degree of similarity is less important. Here one has to consider "how it came about that the small piece of paper one holds in one's hand was given the configuration of grey tones and colours that one now sees. Thus, one has to make an abductive reflection that traces the chain of causes and considerations. As always when reading traces, the traces 'say' nothing until you ask them questions [...]"6 Now it becomes exciting, because the index is a sign that does not simply reveal information. It merely points to something, but in no way says what conclusions can be drawn from it. Kj0rup also goes into this peculiarity of the index and describes: "For example, a detective might be interested in the thickness of the packages of stolen banknotes that were apparently in front of the lens when the camera's closing mechanism was triggered, [...] a photo historian might be interested in whether the structure of the photograph might reveal whether a certain lens or a certain type of development paper has been used. In the indexical reading of a photograph, there is no one who wants to tell us anything, there is no communicative intention. Here there are only traces or symptoms of a reality, signs whose interpretation requires expert
knowledge"7. This means that it always depends on the question asked of a photograph. Whether there is similarity is not the decisive factor, but whether and to what extent there is a causal connection.
In this context the problem that index theory has is that the "inscription metaphor" is very vague8, or rather: neither Peirce nor one of the authors after him, specify how the transfer of the index from the object to the image carrier takes place. Philippe Dubois at least addresses this circumstance and concludes that the index of a photograph is created exactly at the brief moment when the shutter is released and the light inscribes itself on the film. In this moment, the index is free of any social or historical coding. At this point one can search for it, yet it remains hidden, for every attempt at interpretation presupposes a cod- — ing. This means that photographs are indexical, but the index itself cannot appear - unless superimposed by coding. This coding includes the question one poses to the index. With reference to Roland Barthes' rhetoric of the picture, one can show that every description of a picture necessarily entails an interpretation, because when viewed through one's own prior knowledge and familiar visual impressions, meaning is drawn from the signs considered.
Mirjam Lewandowsky also explores the question of where the indexicality of a photograph can be located and describes: "The trace or imprint character that Peirce generally ascribes to indexical signs seems to complicate itself in a photograph. In contrast to other indexical signs,
5 Soren Kjorup, Semiotik, utb Profile, Band 3G39, (München: Fink 2GG9), p. 65.
6 Ibid.
7 S0ren Kj0rup, Semiotik, utb Profile, Band 3039, (München: Fink 2009), p. 65f.
8 cf. Peter Geimer, Theorien der Fotografie zur Einführung (Hamburg: Junius, 2009), p. 58f.
| 4 (37) 2019 |
Ясмин КАТХЁФЕР / Jasmin KATHOFER
| Не «что такое индекс?», а «индекс - он какой»? О различении фотографических индексальностей / Not what, but HOW is the Index? On the Differentiation of the various Indexicalities of Photography |
photographs can only be indexed retrospectively. Only when the photographic print is available can it be retrospectively concluded that it is an indexi-cal connection."9 Here she rightly draws attention to a strangeness that is often not directly noticeable when describing the indexicality of photographs. The indexicality of photographs seems "to have always been conveyed, since the visible print is the first thing that sets the talk of indexicality in motion."10 But the index comes into being much earlier - when the film is inscribed on the lightsensitive film. However, this index is not yet fixed. The image is latent until the film is developed and negatives are created, from which prints can finally be taken. The inscription itself remains invisible, the (medial) process until the print is available is suppressed (or simply forgotten)11. Philipp Reinfeld in his study Image-Based Architecture. Fotografie und Entwerfen: "The index theory of the photographic image overlooks [... ] that it is always the technical medium that mediates between reality and image. Even if it itself does not appear immediately, as a 'figure of the centre' it is the central instance by means of which 'something reaches the appearance, representation is given, references are made and meanings are produced'. The medial interspace thus remains a blind spot for the index theory, which is not ex-
9 Mirjam Lewandowsky, Im Hinterhof des Realen. Index - Bild - Theorie (Paderborn: Fink, 2016), p. 71.
10 Ibid, p. 73.
11 cf. Christopf Hoffmann, „Die Dauer eines Moments. Zu Ernst Machs und Peter Salchers ballistischfotografischen Versuchen 1886/87," in Geimer, Peter
(ed.) Ordnungen der Sichtbarkeit. Fotografie in Wissenschaft, Kunst und Technologie (Frankfurt/Main:
Suhrkamp, 2002), p. 356.
plained, but mystified and withdrawn from thought."12
From these statements it becomes clear that in order to deal with the index it is highly necessary to clarify the role of the 'medial interspace' - i.e. to show how the transfer of the index from the object to the sign carrier functions. This includes the recording of the index as well as the stabilization of the index as a 'finished image'. For this reason, various photographic methods are examined in the following with regard to their recording and stabilization. However, the optical projection in the camera is to be excluded for this text, which plays a role for the inscription, but a negligible one here.
2. Photographic Techniques
In order for photography to be invented, two basic prerequisites had to be met. Firstly, optics had to be developed to such an extent that it was physically possible to project an 'image of nature' precisely onto a matte screen.13 Secondly, one needed knowledge in the field of chemistry, i.e. one had to find out how one could chemically fix images. In 1727 Johann Heinrich Schulze, who recognized that chloride silver blackened under the influence of light, and Carl Wilhelm Scheele made important observations in this respect. He also discovered the effect of light on chloride silver, but was also able to determine "that the chloride silver blackened by light is no longer com-
12 Philipp Reinfeld, Image-Based Architecture. Fotografie und Entwerfen (Paderborn: Fink, 2018), p. 99.
13 For the history of photographic optics see, among others, Joseph Maria Eder, Geschichte der Photographie (Halle/Saale: Wilhelm Knapp, 1905) and Heinz Haberkorn, Anfänge der Fotografie. Entstehungsbedingungen eines neuen Mediums (Hamburg: Rowohlt 1981).
14
| 4 (37) 2019 |
Ясмин КАТХЁФЕР / Jasmin KATHOFER
| Не «что такое индекс?», а «индекс - он какой»? О различении фотографических индексальностей / Not what, but HOW is the Index? On the Differentiation of the various Indexicalities of Photography |
pletely soluble in ammonia, but leaves finely divided black silver, which does not change further and provides a final image"14. A discovery that remained unknown for a long time. It was also observed that sodium thiosulfate can be used as a fixing agent for photographs. Daguerre, for example, did not use it until 1839 to fix his photographs.15
Let's recall Charles Sander's Peirce statement: then a photograph is indexical because there is a causal relationship between object and image - whether through direct contact, as in a photogram, or transmitted contact via light falling through a lens - one has to ask oneself how the index (which has already been optically transmitted) can be fixed on the respective carrier material. Carrier materials can be for example metal, glass, fabric or porcelain, but also paper and film. For this essay I will limit myself to the last two image carriers and will also discuss digital photography, which in its appearance should be regarded as a data set.
2.1 Salted paper
Salted paper is paper containing chloride silver. William Henry Fox Talbot worked with such paper for his photogenic drawings. That is why prints of salted paper negatives are also called calotype or talbotype. To produce the paper, high-quality writing paper was soaked with a saline solution (sodium chloride), dried and coated in a silver nitrate solution that was dried over fire, resulting in the light-sensitive silver nitrate.16
14 Heinz Haberkorn, Anfänge der Fotografie. Entstehungsbedingungen eines neuen Mediums (Hamburg: Rowohlt, 1981), p. 25.
15 cf. Ibid.
16 cf. Robert Knodt and Klaus Pollmeier, Verfahren der Fotografie (Essen: Folkwang, 1989), p. 58, Heinz
"Evolving took about five to ten minutes in full sunlight, or one [sic!] half an hour to several days in diffuse [sic!] light."17 The surface of the salted paper is matt. In the print, the collodial structure of the silver produces "warm tones from yellowish and reddish brown to brown, purple and black"18. It is also typical that the image gradually fades or otherwise decomposes. An image on salted paper, when observed through a 20x magnifying glass, is visible as being directly in the structure of the paper (paper fibres are recognizable). This proves that this sort of paper has only one layer.
2.2 Albumen print
The situation is different with albumen print (used from 1850 to around 1920), which has a layer of protein in which the light-sensitive salt layer lies, thus preventing it from sinking into the 15 paper felt. Thus albumen paper also offers a higher contrast and blackness. "The paper was evolved in a frame in contact with a hard negative in full daylight. In summer 10-15 minutes were enough in bright light, in winter it took between one and several hours."19 Typical for albumen prints is the strongly yellowed emulsion layer - "an error that often occurred after only a few months [...] The colours of the gold toning determine the warm image tone. The image surface varies between semimatt and glossy [...] Cracks in the emulsion layer are often visible to the naked eye. The paper fibres can be clearly seen in lights and shadows with a
Haberkorn, Anfänge der Fotografie. Entstehungsbed-
ingungen eines neuen Mediums (Hamburg: Rowohlt,
1981), p. 64.
17 Robert Knodt and Klaus Pollmeier, Verfahren der Fotografie (Essen: Folkwang, 1989), p. 58.
18 Ibid.
19 Ibid, p. 59.
| 4 (37) 2019 |
Ясмин КАТХЁФЕР / Jasmin KATHOFER
| Не «что такое индекс?», а «индекс - он какой»? О различении фотографических индексальностей / Not what, but HOW is the Index? On the Differentiation of the various Indexicalities of Photography |
magnifying glass (20x). The thin, strongly rolling paper is almost always mounted on cardboard"20.
2.3 (Bromide)Silver gelatin paper
Another example of a type of photographic paper is bromide or chlorobromide silver gelatin paper, which "has a thick barite layer under the emulsion that completely covers the paper fiber. The base material is solid paper or thin card-board"21. The process was developed in 1884 and is still in use today. Since the early 1970s, polyethylene papers have also been used as a carrier material. They have a white layer underneath the emulsion and a clear polyethylene layer on the back. Therefore, there is no paper fibre visible in the image whites of both paper and PE paper - not even with the aid of a magnifying glass.
According to Maria Bortfeldt, a photo restorer at the Berlinische Galerie and the Landesmuseum für Moderne Kunst, Photographie u. Architektur, the three basic types of photographic paper can be distinguished on the basis of the paper fibre: 1. papers with only one layer, which makes the writing paper clearly recognizable (such as the salted paper, but also, for example, in cyanotype paper), 2. papers with two layers, as in the case of albumen paper, slightly glossy, but the fibre is still visible, and 3. Papers with three layers, which are clearly distinguishable from writing paper, or the fibre is no longer visible, as in the last example of bromine or chlorobromide silver gelatin paper.
The production of this kind of paper has always been exclusively industrial. The lightsensitive layer consisted mainly of bromide silver, but in order to achieve different gradations it was
mixed with chloride or iodide silver. The colours obtained vary from neutral black or a cool blue-black (bromine) to slightly warm-black (chloro-bromide) or sometimes slightly greenish (chlorine). If iodized silver were used, a yellowish tone would be achieved.22
The bromide silver gelatin paper was not evolved on printing out paper, but developed and fixed. In the beginning, diluted negative developers were used, as special paper developers first had to assert themselves. With some PE papers, developer substances are already added during production. "This makes extremely short development times of a few seconds possible. The normal times are between one and three minutes."23 Older or poorly processed paper and PE paper stored under unfavourable storage conditions can show signs of decomposition or brittle or fragile — carrier material.
2.4 Gum bichromate
The Gum bichromate print is a slightly different way of developing a photograph. Gum bichromate printing is a printing process on paper in which (especially in Germany) several layers are printed on top of each other in order to obtain multi-coloured images. The emulsion consists of "gum arabica dissolved in water, dichromate salt and pigment. [...] The paper had to have a certain surface structure for the rubber solution to adhere well."24 Solid watercolour paper was used, which was usually reglued with gelatin or starch solution before use. Exposure was made with a rather soft negative in UV or sunlight. This partially cured the rubber layer. The remains were removed in a
20 Ibid.
21 Ibid, p. 64.
22 cf. Robert Knodt and Klaus Pollmeier, Verfahren der
Fotografie (Essen: Folkwang, 1989), p. 64.
23 Ibid.
24 Ibid, p. 71.
| 4 (37) 2019 |
Ясмин КАТХЁФЕР / Jasmin KATHOFER
| Не «что такое индекс?», а «индекс - он какой»? О различении фотографических индексальностей / Not what, but HOW is the Index? On the Differentiation of the various Indexicalities of Photography |
bowl with cold water. This process was repeated several times until the desired tonal values were achieved. Depending on how many layers were exposed, this could take several hours. "Gum bichromate prints are extremely well preserved. [... ] In the lights, the paper fibre can be clearly seen with a magnifying glass (20x). With thick rubber layers the shadows begin to shine."25 There the paper fiber is covered - especially if many layers were printed on top of each other. In addition, rubber printing is clearly distinguishable from silver salt based processes solely because of its range of colour tones.26
What hopefully became clear with this short overview is that over the course of time there were, influenced by innovations in photography, different ways to develop a photograph and to fix it on paper (thus stabilizing the index). The results varied in appearance and also required a different duration of fixation - from a few minutes to several days. The carrier material thus provides information about which method was used and is therefore an important source of information for historical photo sources (keyword: dating). Above all, however, it can be shown that:
1. there is a varying temporality in the stabilization of the index within different photo methods. Salted paper: 10 minutes to several days. Albumen paper: 10 minutes to several hours.
25 Ibid.
26 The technical details of the photographic processes
are based on the texts by Robert Knodt and Klaus Pollmeier, Verfahren der Fotografie (Essen: Folkwang, 1989), Timm Starl, Bildbestimmung. Identifizierung und Datierung von Fotografien 1839 bis 1945 (Jonas: Marburg, 2009) and Heinz Haberkorn, Anfänge der Fotografie. Entstehungsbedingungen eines neuen Mediums (Hamburg: Rowohlt, 1981).
Bromide or chlorobromide silver gelatin paper: a few seconds to three minutes. Gum bichromate: several hours, depending on the amount of coating.
2. the chemical processes vary and are reflected in the colour and paper quality.
This is where we can now consider the photographic index within today's photographic processes. If there are observable differences in the processes sketched so far, why shouldn't something similar show in photographic processes that are now accessible en masse? These methods are analog photography on film, instant imaging, and digital photography using various devices. Since the optical recording of cameras is not very different, but the processes and steps that take place from the moment a camera is actuated differ -1— - as could already be seen with the various methods on paper - it is now necessary to compare the methods with each other in order to draw conclusions about their different indexicalities.
2.5 Colour film/photographic paper
The structure of colour film and colour photographic paper is basically identical. Film and paper consist of several layer: the halation protection and the layer carrier, topped with layers sensitive to blue (yellow layer), green (purple layer) and red light (cyan or blue-green layer), as well as a yellow filter layer that prevents blue light from reaching deeper layers. "With negative film, blue, which has exposed the yellow layer, becomes yellow, green becomes purple and red becomes blue-green."27 During the paper development, it is the
17
27 Elmar Baumann, „Fotografie-Informationen. Aufbau des Farbfilms", URL: https://www.elmar-baumann.de/fotografie/fotobuch/node24.html, last access: 16.11.2019.
| 4 (37) 2019 |
Ясмин КАТХЁФЕР / Jasmin KATHOFER
| Не «что такое индекс?», а «индекс - он какой»? О различении фотографических индексальностей / Not what, but HOW is the Index? On the Differentiation of the various Indexicalities of Photography |
same process but reversed. A negative of the negative is created: a positive. "In the paper image, white is created, where all three colour layers are completely exposed in the negative film. The negative is black and opaque at these places. When enlarging, the photo paper does not get any light there and remains white."28 Finally, the gelatin layer serves as a protective layer against scratches.
After the colour film has been exposed in the camera, a latent image is created. In order to fix this, the film must first be developed into negatives before a print can be made from that negative. The production of a print takes place in several steps. After the exposure of the photo paper, it is developed in the developer bath. This process is then interrupted in the acid stop bath, only then can the image be fixed. The process takes a few minutes and is completed after washing it in clear water and drying.
2.6 Instant film
Photographs made by Instand film have undergone a revival in recent years, so that there are now several suppliers of such cameras. "Polaroid films [but also films from other manufacturers such as Fuji] consist of three basic elements: negative material on a transparent carrier, transfer paper and a capsule with developer paste."29 For this reason, black-and-white instant images were also referred to as a "unit of film material, camera and laboratory"30 when they were
28 Elmar Baumann, „Fotografie-Informationen. Aufbau des Farbfilms", URL: https://www.elmar-baumann.de/fotografie/fotobuch/node24.html, last access: 16.11.2019.
29 Robert Knodt and Klaus Pollmeier, Verfahren der Fotografie (Essen: Folkwang, 1989), p. 80.
30 Ibid.
introduced in 1947. "After the film has been exposed, the developer paste is squeezed out of the camera as a thin layer between the negative and the transfer paper and produces a negative silver image by fixation development. It remains on the negative material, but the unexposed silver salts diffuse onto the transfer paper and are developed there"31. In the case of instant image colour film, dyes diffuse instead of silver salts. "The negative consists of three black-and-white emulsions, each with an adjacent dye layer and two separating layers."32 The fixing process takes only a few seconds. The image then develops in a short time in daylight. Round about applies: a few seconds for black and white, one to three minutes for colour images, whereby one can observe how the colour crystals develop slowly. In the case of Knodt and Pollmeier it can be read that most Polaroid films have a printed longer combination of numbers and letters and/or the company name on the back, that designate the type of film, date of manufacture and other data.
3. Digital photography - Digital indexicality
Digital photography is created by a process in which the light projection into the camera functions in exactly the same way as that of an analogue camera, but which no longer takes place chemically. This change was at the center of the discussion broke out at the end of the 1990s about whether one had arrived in the post-photographic age.
With the media upheaval from analog to digital, the much-discussed index concept of photography and film theory began to waver - the in-dexicality and thus the claim of truthfulness of
18
31 Ibid.
32 Ibid.
| 4 (37) 2019 |
Ясмин КАТХЁФЕР / Jasmin KATHOFER
| Не «что такое индекс?», а «индекс - он какой»? О различении фотографических индексальностей / Not what, but HOW is the Index? On the Differentiation of the various Indexicalities of Photography |
photography and film were declared dead because of their digital recording process. Famous representatives of this assumption are Stewart Brand, W.J.T. Mitchell and Bernd Stiegler.33 The main reasons for this were the easy manipulability and retouch-ability of digital photos and thus the loss of a photo's evidential value, but above all the loss of its relation to reality. A reference that is not only reflected in the critics' assumptions - such as Martin Doll's essay Entzweite Zweiheit? Zur In-dexikalitat des Digitalen writes - only analog photography, by means of well-known previous speakers (such as Roland Barthes, André Bazin, Sigfried Krakauer, Susan Sontag, etc) can be ascribed to it.34 With regard to easy manipulability or, to put it better, simple intervention and alteration of digital photographs, Doll claims: "Beyond authentication by authoritative quoting, however, in the current debate it often remains unfounded why analog photography should automatically have an evidence character. For the history of well-known analog counterfeits, or rather manipu-
33 cf. Stewart Brand, Kevin Kelly and Jay Kinney, „Digital Retouchug. The Ende of Photography as Evidence of Anything," in Whole Earth Review, H. 47(Juli 1985), pp. 42-47, William J. Mitchell, The Reconfigured Eye. Visual Truth in the Post-Photographic Era (Cambridge: Mass 2001), Bernd Stiegler, „Digitale Fotografie als epistemologischer Bruch und historische Wende," in Lorenz Engell, Britta Neitzel, (eds.), Das Gesicht der Welt. Medien in der digitalen Kultur (München: Fink, 2004), pp. 105-126.
34 This is a debate that I do not want to reopen here for reasons of length alone (for further discussion, see, for example, Martin Doll, „Entzweite Zweiheit? Zur In-dexikalität des Digitalen," in Segeberg, Harro (ed.) Film im Zeitalter Neuer Medien II. Digitalität und Kino (Paderborn: Fink 2012; Peter Geimer, Theorien der Fotografie zur Einführung (Hamburg: Junius, 2009), Mirjam Lewandowsky, Im Hinterhof des Realen. Index - Bild - Theorie (Paderborn: Fink, 2016).
lations and dissimulations, makes it questionable even in early photography whether they were perceived by the viewer as irrefutable pieces of evidence: Think, for example, of Oscar Gustave Re-jlander's artistic compositions from 1857"35, in which groups of people were assembled from individual photographs. With regard to the film, he also speaks of the speeding effect, in which a film was played with 16-18 frames per second at 24 frames/second36. These examples show how analog images have been altered or alienated. Manipulability can therefore not be a criterion for distinguishing between analogue and digital.
If both analogue and digital recordings can be altered, it is questionable to what extent the in-dexical connection to reality (as what people can see with their own eyes and touch with their hands to understand in colloquial terms) actually exists. — Doll talks here about the evidence character ascribed to photographs by the index. But it is not at all compelling that an index is evident at the same time. An index is an empty sign that merely points to something, but in no way says what conclusions can be drawn from it37. As a reminder: "In the in-dexical reading of a photograph, there is no one who wants to tell us anything, there is no communicative intention. Here there are only traces or symptoms of a reality, signs whose interpretation
35 Martin Doli, „Entzweite Zweiheit? Zur Indexikalität des Digitalen," in Segeberg, Harro (ed.) Film im Zeitalter Neuer Medien II. Digitalität und Kino (Paderborn: Fink 2012), p. 62f.
36 cf. Martin Doll, „Entzweite Zweiheit? Zur Indexikalität des Digitalen," in Segeberg, Harro (ed.) Film im Zeitalter Neuer Medien II. Digitalität und Kino (Paderborn: Fink 2012), p. 66.
37 cf. Winfried Nöth, Handbuch der Semiotik. 2., voll-
ständig neu bearbeitete und erweiterte Auflage
(Stuttgart/Weimar: Metzler, 2000), p. 185.
| 4 (37) 2019 |
Ясмин КАТХЁФЕР / Jasmin KATHOFER
| Не «что такое индекс?», а «индекс - он какой»? О различении фотографических индексальностей / Not what, but HOW is the Index? On the Differentiation of the various Indexicalities of Photography |
requires expert knowledge"38 Evident, on the other hand, is something that is unambiguous. Something that gives immediate and complete insight into, again, something. Of course, these can also be images that have an indexical reference to a real existing object (or event), but this connection is by no means a must. Rather, it is a "linkage of knowledge to a symbol"39, which can also be indexical, but does not have to be. Likewise, to be indexical, images do not necessarily have to be evident.
Jens Schröter writes in his text Gestaltung und Referenz in der analogen und digitalen Fotografie (Design and Reference in Analogue and Digital Photography) about an entirely analogue image which, according to theory, must be indexi-cal. "But that doesn't help, because if you don't know what it's all about, you can't see anything. You can't see what's important about this photo. You may not even be able to say what it represents. You may not even be able to see the picture, that it is a (scientific) photograph, it could also be some kind of experimental drawing. You can't point to the photo - with the gesture Barthes so beautifully describes in the Bright Chamber: 'that's exactly that, that's the one'."40
And indeed: In the photograph you can see a scribble of thin lines, circles and dots. No object can be identified that could be named, but nevertheless the photograph acts as evidence. It shows a
38 S0ren Kj0rup, Semiotik, utb Profile, Band 3039, (München: Fink 2009), p. 65f.
39 Rolf F. Nohr, Nützliche Bilder. Bild, Diskurs, Evidenz (Münster: Lit, 2014), p. 304.
40 Jens Schröter, „Gestaltung und Referenz in der analogen und digitalen Fotografie," in Claudia Mareis, Christof Windgätter (eds.), Long Lost Friends. Wechselbeziehung zwischen Design-, Medien- und Wissenschaftsforschung (Berlin: diaphanes, 2013), p. 69.
so-called Golden Event from the field of particle physics - the photo No. 97025, which recorded the trace of the omega minus (Q-) particle and thus proved its existence.41 So you can see that the indexical connection does not necessarily have to be recognizable (for everyone) in order to be there. But if similarity, evidence and possibilities of changing a photograph (or even the film) are not criteria for talking about indexicality (or naming its existence), then it must be the causal connection to reality that plays the decisive role. Only when it has been clarified how this connection arises can the index be understood as such. Finally, according to Peirce, the prerequisite for an indexical sign is that its object must actually exist in time and space. "Because an index is an effect-determined sign, and non-existent things have no effect."42
But how does the transmission of light come about in digital photography? First of all, as Wolfgang Hagen explains, a distinction must be made between "image processing (mathematical image processing techniques), computer graphics (techniques of algorithmic image generation), and electronic signal storage (semiconductor/CCD technology)"43. Computer graphics, i.e. computergenerated images, shall be ignored for my viewing. So this is only about digital pictures taken with a digital camera. The digital recording works
20
41 cf. Jens Schröter, „Gestaltung und Referenz in der analogen und digitalen Fotografie," in Claudia Mareis, Christof Windgätter (eds.), Long Lost Friends. Wechselbeziehung zwischen Design-, Medien- und Wissenschaftsforschung (Berlin: diaphanes, 2013), p. 69ff.
42 Charles Sanders Peirce, Semiotische Schriften (Frankfurt/Main: Suhrkamp, 2000), p. 414.
43 Wolfgang Hagen, „Die Entropie der Fotografie. Skizzen zu einer Genealogie der digitalelektronischen
Bildaufzeichnung," in Herta Wolf (ed.), Paradigma
Fotografie (Frankfurt/M.: Suhrkamp, 2002), p. 195.
| 4 (37) 2019 |
Ясмин КАТХЁФЕР / Jasmin KATHOFER
| Не «что такое индекс?», а «индекс - он какой»? О различении фотографических индексальностей / Not what, but HOW is the Index? On the Differentiation of the various Indexicalities of Photography |
until the light falls on the image plane, just like the analog recording. Only the fixation or further processing of the latent image differs. In both cases, therefore, light is inscribed. Digital photographs are therefore indexical "in the sense that light is reflected by the object (or a model) and falls on a sensor - only that the sensor is no longer photochemical, but quantum-electronic. Hagen's argument that digitally recorded photographs, unlike chemical photographs, are erasable, i.e. reversible, does not change this either44. PhotoGraphy' means 'writing of light', nothing in this term determines whether the recording is analog or digital, permanent or fleeting."45
The sensor, a charge-coupled device, or CCD sensor for short, measures the light or brightness - depending on how much light falls on the light-sensitive points (diodes or pixels) of the sensor grid. The basis of the sensor is a semiconductor. The colour information is obtained by colour filters (mosaic filters, mostly Bayer) that are located upstream of the semiconductor. The light that falls on this semiconductor is "transformed into electrons"46. This is done by the photoelec-
44 Wolfgang Hagen, „Die Entropie der Fotografie. Skizzen zu einer Genealogie der digitalelektronischen Bildaufzeichnung," in Herta Wolf (ed.), Paradigma Fotografie (Frankfurt/M.: Suhrkamp, 2002), p. 231ff, cited from Jens Schröter, „Gestaltung und Referenz in der analogen und digitalen Fotografie," in Claudia Ma-reis, Christof Windgätter (eds.), Long Lost Friends. Wechselbeziehung zwischen Design-, Medien- und Wissenschaftsforschung (Berlin: diaphanes, 2013), p. 93.
45 Jens Schröter, „Gestaltung und Referenz in der analogen und digitalen Fotografie," in Claudia Mareis, Christof Windgätter (eds.), Long Lost Friends. Wechselbeziehung zwischen Design-, Medien- und Wissenschaftsforschung (Berlin: diaphanes, 2013), p. 93.
46 Wolfgang Hagen, „Die Entropie der Fotografie. Skizzen zu einer Genealogie der digitalelektronischen
tronic effect in which photons hit the semiconductor and release electrons from its valence band structure. At the point where the electron was located, a hole is formed which is positively charged and (like the electron) movable.47 The released electrons migrate under the pixels and are collected by means of a "sophisticated circuit logic [...]. The electrons generated from light remain there, pixel by pixel as in tiny buckets of electrons. A further circuit trick transports the buckets to the edge of the chip, where their content (electrons) is counted, i.e. charged. These measured values can then (do not) have to be converted digitally into bit patterns (= numbers)"48.
To make this work, the electron number is increased by means of a preamplifier or the signal of the sensor is amplified. The "image information is brought into a discrete mathematical form", i.e. — the image is "decomposed into a finite number of uniquely identifiable geographical pixels and each of these pixels [...] is assigned a tonal value from a predefined, finite tonal value range"49. In digital cameras, the light sensitivity of the sensor and thus the ISO (or gain) number can be adjusted in this way, similar to what is possible with different film types in analog photography. At the same time, the conversion to digital values is the only digital to digital photography. The remaining pro-
Bildaufzeichnung," in Herta Wolf (ed.), Paradigma Fotografie (Frankfurt/M.: Suhrkamp, 2002), p. 217.
47 cf. Ibid, p. 220f.
48 Wolfgang Hagen, „Die Entropie der Fotografie. Skizzen zu einer Genealogie der digitalelektronischen Bildaufzeichnung," in Herta Wolf (ed.), Paradigma Fotografie (Frankfurt/M.: Suhrkamp, 2002), p. 222.
49 Simon Brugner, Über die Realität im Zeitalter digitaler Fotografie (Boitzenburg: vwh, 2012), p. 42.
| 4 (37) 2019 |
Ясмин КАТХЁФЕР / Jasmin KATHOFER
| Не «что такое индекс?», а «индекс - он какой»? О различении фотографических индексальностей / Not what, but HOW is the Index? On the Differentiation of the various Indexicalities of Photography |
cess just described is quantum mechanical50 and is therefore subject to a physical change in the values within the sensor from which the image is retrieved. Peirce himself would therefore hardly doubt that this is a causal relationship. The fact that a conversion into numbers takes place can hardly be used as a counter-argument, since Peirce also cites barometer displays and other measuring instruments with number scaling as indexical me-dia51. What is interesting about digital photographs is that they can be displayed both as a series of numbers and as an image, whereas "in the chemical-physical film process, the light data received can only be converted or translated visually" - indexical "digital signals are much more open to results and meanings with regard to their mode of representation"52. This leads to the conclusion that other (i.e. not photographic) digital measured values that have a causal connection to an object or event are also indexical, because whether something is indexical does not depend on whether it is an image53.
50 cf. Wolfgang Hagen, „Die Entropie der Fotografie. Skizzen zu einer Genealogie der digitalelektronischen Bildaufzeichnung," in Herta Wolf (ed.), Paradigma Fotografie (Frankfurt/M.: Suhrkamp, 2002), p. 222.
51 cf. Winfried Nöth, Handbuch der Semiotik. 2., vollständig neu bearbeitete und erweiterte Auflage (Stuttgart/Weimar: Metzler, 2000), p. 185.
52 Martin Doll, „Entzweite Zweiheit? Zur Indexikalität des Digitalen," in Segeberg, Harro (ed.) Film im Zeitalter Neuer Medien II. Digitalität und Kino (Paderborn: Fink 2012), p. 83f.
53 cf. Martin Doll, „Entzweite Zweiheit? Zur In-
dexikalität des Digitalen," in Segeberg, Harro (ed.)
Film im Zeitalter Neuer Medien II. Digitalität und Kino (Paderborn: Fink 2012), p. 84, on the existence of the digital image see Wolfgang Hagen, „Es gibt kein ,digitales Bild'. Eine medienepistemologische Anmerkung," in Lorenz Engell, Bernhard Siegert, Joseph Vogl (eds.), Licht und Leitung (Weimar, 2002), pp.
The process of recording, processing and storing a digital image takes place within seconds, so the photo can be viewed immediately. As a data record, the digital photo can be permanently stored and retrieved - at least as long as no problems occur during retrieval, e.g. because a certain file format is no longer compatible.
W. J. Mitchell claims in The Reconfigured Eye that a digital image file can be copied infinitely without suffering a loss of quality54. This may be true, but Lev Manovich notes that reality is not as simple as Mitchell suggests. Manovich describes that copying digital photographs results in greater losses of information and quality than assumed: "A single digital image consists of millions of pixels. These files require considerable storage space in a computer. Unlike a text file, it 22 also takes a long time to send a digital image over — a network. For this reason, all currently available software and hardware for loading, storing, editing, and transmitting digital images is based on data-reducing compression - a technique that makes image files smaller by deleting a certain amount of information."55 This happens at the expense of image quality. At this point it should be
103-112, Claus Pias, „Das digitale Bild gibt es nicht. Über das (Nicht-)Wissen der Bilder und die in-formatische Illusion," in zeitenblicke, 2(1) 2003, URL: www.zeitenblicke.de/2003/01/pias/pias.pdf, last access: 13.10.2019), Jens Schröter, "Digitales Bild" in Image 25 (2017), pp. 89-106.
54 cf. William J. Mitchell, The Reconfigured Eye. Visual Truth in the Post-Photographic Era (Cambridge: Mass, 2001), p. 6.
55 Lev Manovich, „Die Paradoxien der digitalen Fotografie," in Amelunxen et al (eds.), Fotografie nach der Fotografie (Dresden: Verlag der Kunst, 1996), p. 60, cf. Peter Lunenfeld, „Digitale Fotografie. Das dubitative Bild," in Hertha Wolf (ed.), Paradigma Fotografie (Frankfurt/Main: Suhrkamp, 2000), p. 164.
| 4 (37) 2019 |
Ясмин КАТХЁФЕР / Jasmin KATHOFER
| Не «что такое индекс?», а «индекс - он какой»? О различении фотографических индексальностей / Not what, but HOW is the Index? On the Differentiation of the various Indexicalities of Photography |
noted that this is not a problem of the 1990s, but still occurs on platforms such as Instagram.56 Accordingly, digital photographs, like analog photographs, are not spared a loss of quality.
The fact that digital photographs store not only the image information but also so-called meta data when they are taken should also be briefly addressed. Meta data is the information about time, date, location of the photograph, lens used, iso number, etc.. Winfried "Gerling speaks in this context of an extension or duplication of the photographic indexicality, because the photograph no longer only indicates the depicted objects or events, but also the when, how and where of its own production."57
4. How is the Index?
If one looks at the various photographic procedures and recording techniques, it can be seen that inscription takes place by different means over a certain period of time and that different steps have to be taken. As the technology progressed, the duration of the image forming process became ever shorter and the steps to be taken ever smaller.
Simon Brugner notes that analogue and digital photographs do not differ in their aesthetic effect and that the type of recording is subject to the same optical principle. Even though the digital nature of the images could be seen at the begin-
56 The Mystery of Low Quality Images in Instagram and VSCO: https: //www. reddit. com/r/Android/ comments/2rq1wg/t he_mystery_of_low_quality_images_in_instagram/
57 Susanne Holschbach, „Das verteilte Bild. Erscheinungsweisen und Performanzen digitaler Fotografie," in
Ilka Becker et.al. (eds.), Fotografisches Handeln. Das fotografische Dispositiv Band 1 (Marburg: Jonas, 2016), p. 128
ning, this was obsolete due to the progressive further development of technology and no difference could be seen with the naked eye.58
However, the methods that involve paper have shown that someone who has the right know-how - and I remind you that, with regard to the index, it is important whatever question you ask of it - can infer the conditions of its production from the material nature of a photograph. Modern photographic papers and instant films are usually marked on the reverse side with numbers that allow conclusions to be drawn about the production of the paper or film and thus also about the year of taking and the date of development. Digital photos have metadata of varying detail, which can be consulted for this purpose. Most camera and smartphone manufacturers use a mixture of Exif, 23 IPTC and XMP information that any user can read — out via online tools or certain programs, but which are also used by social media platforms. In any case one has to deal with a historical index. However, the different procedures also need a different time span to stabilize the index, and this is done using different practices. So there is no general way to transfer the index, but there are many possibilities.
Irrespective of what is depicted on a photograph, there are therefore possibilities for differentiation which are related to the material composition of a photograph. These also come into view if the image is blurred, completely out of focus or - in the case of digital recording - strongly pixe-lated. The same applies to the aging processes of analogue photographs, the quality of which declines over the years. As already mentioned, digi-
58 Simon Brugner, Über die Realität im Zeitalter digitaler Fotografie (Boitzenburg: vwh, 2012), p. 49f.
| 4 (37) 2019 |
Ясмин КАТХЁФЕР / Jasmin KATHOFER
| Не «что такое индекс?», а «индекс - он какой»? О различении фотографических индексальностей / Not what, but HOW is the Index? On the Differentiation of the various Indexicalities of Photography |
tal photos are not immune to loss of quality, be it due to compression or obsolete technology.
One example is provided by Hito Steyerl in her book Die Farbe der Wahrheit. Dokumentar-ismen im Kunstfeld that deals with the recording of a mobile phone camera from 2003 that was made during the first days of the Iraq invasion: "A correspondent sat on an armored army vehicle and held a mobile phone camera out of the window. The images from this camera were transmitted directly - live from the war. The correspondent was euphoric. He cheered: You have never seen such pictures before! Indeed - there was hardly anything to be seen on the pictures. Due to a lack of resolution, they looked like green-grey coloured areas that slowly moved across the screen. They resembled a military camouflage paint. Abstract compositions whose resemblance to what they were supposed to represent could only be guessed"59. According to Steyerl, these images are not documentary in the classical sense, since there is no similarity between them and reality. But she also says that, despite their blurriness or precisely because of this blurriness, they seem genuine (ibid.), that the blur is a reflection of the general "intransparency and uncertainty of an entire epoch. The abstract pixels that float across the television screen are the crystal-clear expression of a time in which the connection between images and things has become questionable and is under general suspicion."60
Similarity, however, is not mandatory for the question of indexicality, since - as shown above - the effect of light on the CCD sensor involves a physical-causal connection between what
is shown and the source of it. If one sees the blurred images without their context, it could be any source, but the image would still be indexical. The viewer is only not able to decipher what the image is about, and in this case this is solely due to the poor quality of the mobile phone camera. For comparison: The Sony Ericsson T610 or the Samsung SGH-V20 from 2003 had a resolution of 288 x 352 pixels, which corresponds to approx. 0.1 megapixels. The resulting image is tiny and looks even worse on a large monitor than on the device itself. Dean Keep summarizes the conditions of early mobile phone cameras and writes: "The plastic camera lens and the unsophisticated image sensor in early camera phone models made it difficult to achieve accurate renderings of subjects; perspectives were often stretched and col- 24 ours were often muted or over-saturated. The tiny — screen sizes of early model camera phones frequently made it difficult to frame subjects, especially in extreme light conditions"61.
But what conclusion can be drawn from what has been said? I hope that it has become clear that when dealing with indexicality we cannot simply ask: Is the photo analog or digital and is it therefore indexical or not? In an after-postphotographic time this should no longer be the question. This text is intended to sensitize the reader to include all the information when it comes to the interpretation of a photograph. The distinction analog/digital does not become obsolete, but is no longer the only criterion. Stability, duration of fixation, eraseability, loss of details when copied - all these things are revealing, as are
59 Hito Steyerl, Die Farbe der Wahrheit. Dokumentar-ismen im Kunstfeld (Turia + Kant: Wien, 2008), p. 7.
60 Ibid, p. 15.
61 Dean Keep, „Artist with a Camera-Phone. A Dea-cade of Mobile Photography," in Marsha Berry, Max Schleser (eds.), Mobile Media Making in an Age of Smartphones, (Palgrave Pivot, 2014), p. 17.
| 4 (37) 2019 |
Ясмин КАТХЁФЕР / Jasmin KATHOFER
| Не «что такое индекс?», а «индекс - он какой»? О различении фотографических индексальностей / Not what, but HOW is the Index? On the Differentiation of the various Indexicalities of Photography |
any traces of modification or retouching of the image. Digital photographs may and should therefore be described as equivalent indexical. There is not just one way in which a photograph establishes a causal connection to its object. The question should therefore no longer be whether a photograph is indexical, but HOW this indexicality exists.
References:
1. Elmar Baumann (n.d.): „Fotografie-Informationen. Aufbau des Farbfilms", URL: https://www.elmar-baumann.de/fotografie/fotobuch/node24.html, last access: 16.11.2019.
2. Stewart Brand, Kevin Kelly, Jay Kinney, „Digital Retouchug. The Ende of Photography as Evidence of Anything," in Whole Earth Review, H. 47(Juli 1985), p. 42-47.
3. Simon Brugner, Über die Realität im Zeitalter digitaler Fotografie (Boitzenburg: vwh, 2012).
4. Martin Doll, „Entzweite Zweiheit? Zur In-dexikalität des Digitalen," in Segeberg, Harro (ed.), Film im Zeitalter Neuer Medien II. Digital-ität und Kino (Paderborn: Fink 2012), pp. 57-86.
5. Joseph Maria Eder, Geschichte der Photographie (Halle/Saale: Wilhelm Knapp, 1905)
6. Peter Geimer, Theorien der Fotografie zur Einführung (Hamburg: Junius, 2009).
7. Heinz Haberkorn, Anfänge der Fotografie. Entstehungsbedingungen eines neuen Mediums (Hamburg: Rowohlt, 1981).
8. Wolfgang Hagen, „Die Entropie der Fotografie. Skizzen zu einer Genealogie der digitalelektronischen Bildaufzeichnung," in Herta Wolf (ed.), Paradigma Fotografie (Frankfurt/M.: Suhrkamp, 2002), pp. 195-238.
9. Wolfgang Hagen, „Es gibt kein ,digitales Bild'. Eine medienepistemologische Anmerkung," in Lorenz Engell, Bernhard Siegert, Joseph Vogl (eds.), Licht und Leitung (Weimar, 2002), pp. 103-112.
10. Christopf Hoffmann, „Die Dauer eines Moments. Zu Ernst Machs und Peter Salchers ballistischfotografischen Versuchen 1886/87," in Geimer, Peter (ed.) Ordnungen der Sichtbarkeit. Fotografie in Wissenschaft, Kunst und Technologie (Frankfurt/Main: Suhrkamp, 2002), pp. 342-377.
11. Susanne Holschbach, „Das verteilte Bild. Erscheinungsweisen und Performanzen digitaler Fotografie," in Ilka Becker et.al. (eds.), Fotografisches Handeln. Das fotografische Dispositiv Band 1 (Marburg: Jonas, 2016), pp. 111-130.
12. Dean Keep, „Artist with a Camera-Phone. A Dea-cade of Mobile Photography," in Marsha Berry, Max Schleser (eds.), Mobile Media Making in an Age of Smartphones, (Palgrave Pivot, 2014), pp. 14-24.
13. S0ren Kj0rup, Semiotik, utb Profile, Band 3039, (München: Fink 2009).
14. Robert Knodt and Klaus Pollmeier, Verfahren der Fotografie (Essen: Folkwang, 1989).
15. Mirjam Lewandowsky, Im Hinterhof des Realen. Index - Bild - Theorie (Paderborn: Fink, 2016).
16. Peter Lunenfeld, „Digitale Fotografie. Das dubitative Bild," in Hertha Wolf (ed.), Paradigma Fotografie (Frankfurt/Main: Suhrkamp, 2000), pp. 159-177.
17. Lev Manovich, „Die Paradoxien der digitalen Fotografie," in Amelunxen et al (eds.), Fotografie nach der Fotografie (Dresden: Verlag der Kunst, 1996), pp. 58-66.
18. William J. Mitchell, The Reconfigured Eye. Visual Truth in the Post-Photographic Era (Cambridge: Mass, 2001) Rolf F. Nohr, Nützliche Bilder. Bild, Diskurs, Evidenz (Münster: Lit, 2014).
19. Winfried Nöth, Handbuch der Semiotik. 2., vollständig neu bearbeitete und erweiterte Auflage (Stuttgart/Weimar: Metzler, 2000).
20. Claus Pias, „Das digitale Bild gibt es nicht. Über das (Nicht-)Wissen der Bilder und die in-formatische Illusion," in zeitenblicke, 2(1) 2003, URL: www.zeitenblicke.de/2003/01/pias/pias.pdf, last access: 13.10.2019.
25
| 4 (37) 2019 |
Ясмин КАТХЁФЕР / Jasmin KATHOFER
| Не «что такое индекс?», а «индекс - он какой»? О различении фотографических индексальностей / Not what, but HOW is the Index? On the Differentiation of the various Indexicalities of Photography |
21. Charles Sanders Peirce, Semiotische Schriften (Frankfurt/Main: Suhrkamp, 2000).
22. Philipp Reinfeld, Image-Based Architecture. Fotografie und Entwerfen (Paderborn: Fink, 2018).
23. Jens Schröter, „Gestaltung und Referenz in der analogen und digitalen Fotografie," in Claudia Ma-reis, Christof Windgätter (eds.), Long Lost Friends. Wechselbeziehung zwischen Design-, Medien- und Wissenschaftsforschung (Berlin: diaphanes, 2013), pp. 63-76.
24. Jens Schröter, "Digitales Bild" in Image 25 (2017), pp. 89-106.
25. Timm Starl, Bildbestimmung. Identifizierung und Datierung von Fotografien 1839 bis 1945 (Jonas: Marburg, 2009).
26. Hito Steyerl, Die Farbe der Wahrheit. Dokumen-tarismen im Kunstfeld (Turia + Kant: Wien, 2008).
27. Bernd Stiegler, „Digitale Fotografie als episte-mologischer Bruch und historische Wende," in Lorenz Engell, Britta Neitzel, (eds.), Das Gesicht der Welt. Medien in der digitalen Kultur (München: Fink, 2004), pp. 105-126.
26
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