Digital Photography

From deposit to point cloud – A study of low-cost computer vision approaches for the straightforward documentation of archaeological excavations

by Geert Verhoeven

Doneus, M., Verhoeven, G., Fera, M., Briese, Ch., Kucera, M., Neubauer, W. 2011. From deposit to point cloud – A study of low-cost computer vision approaches for the straightforward documentation of archaeological excavations. Geoinformatics 6 (XXIIIrd International CIPA Symposium), 81–88.

Stratigraphic archaeological excavations demand high-resolution documentation techniques for 3D recording. Today, this... more Stratigraphic archaeological excavations demand high-resolution documentation techniques for 3D recording. Today, this is typically accomplished using total stations or terrestrial laser scanners. This paper demonstrates the potential of another technique that is low-cost and easy to execute. It takes advantage of software using Structure from Motion (SfM) algorithms, which are known for their ability to reconstruct camera pose and threedimensional scene geometry (rendered as a sparse point cloud) from a series of overlapping photographs captured by a camera moving around the scene. When complemented by stereo matching algorithms, detailed 3D surface models can be built from such relatively oriented photo collections in a fully automated way. The absolute orientation of the model can be derived by the manual measurement of control points. The approach is extremely flexible and appropriate to deal with a wide variety of imagery, because this computer vision approach can also work with imagery resulting from a randomly moving camera (i.e. uncontrolled conditions) and calibrated optics are not a prerequisite. For a few years, these algorithms are embedded in several free and low-cost software packages. This paper will outline how such a program can be applied to map archaeological excavations in a very fast and uncomplicated way, using imagery shot with a standard compact digital camera (even if the images were not taken for this purpose). Archived data from previous excavations of VIAS-University of Vienna has been chosen and the derived digital surface models and orthophotos have been examined for their usefulness for archaeological applications. The absolute georeferencing of the resulting surface models was performed with the manual identification of fourteen control points. In order to express the positional accuracy of the generated 3D surface models, the NSSDA guidelines were applied. Simultaneously acquired terrestrial laser scanning data – which had been processed in our standard workflow – was used to independently check the results. The vertical accuracy of the surface models generated by SfM was found to be within 0.04 m at the 95 % confidence interval, whereas several visual assessments proved a very high horizontal positional accuracy as well.

Young Children as Digital Image Makers: Reflecting on Lived Experiences of Teaching and Learning

by Narelle Lemon

Aesthetics of serendipity: Muta-morphosis

by Murat Germen

It's All About the Format – Unleashing the Power of RAW Aerial Photography

by Geert Verhoeven

Verhoeven, G., 2010. It's All about the Format – Unleashing the Power of RAW Aerial Photography. International Journal of Remote Sensing 31 (8), 2009-2042.

Current one-shot, handheld Digital Still Cameras (DSCs) generally offer different file formats to save the captured... more Current one-shot, handheld Digital Still Cameras (DSCs) generally offer different file formats to save the captured frames: Joint Photographic Experts Group (JPEG), RAW and/or Tag(ged) Image File Format (TIFF). Although the JPEG file format is the most commonly used file format worldwide, it is incapable of storing all original data, something that also occurs, to a certain extent, for large TIFF files. Therefore, most professional photographers prefer shooting RAW files, often described as the digital photography’s equivalent of a film negative. As a RAW file contains the absolute maximum amount of information and original data generated by the sensor, it is the only scientifically justifiable file format. In addition, its tremendous flexibility in both processing and postprocessing also makes it beneficial from a workflow and image quality point of view. On the other hand, large file sizes, the required software and proprietary file formats remain hurdles that are often too difficult to overcome for many photographers. Aerial photographers who shoot with handheld DSCs should be familiar with both RAW and other file formats, as their implications cannot be neglected. By outlining the complete process from photon capture to the generation of pixel values, additionally illustrated by real-world examples, the advantages and particularities of RAW aerial photography should become clear.

*Chang, S. K., T. T. Lin, G. H. Lin, X. Y. Chang and C. L. Hsieh. 2009. How to collect verifiable length data on tuna from photographs: an approach for sample vessels. ICES Journal of Marine Science, 66: 907-915.

by Shui-Kai Chang

Those who are interested in the software can contact SK Chang at skchang@faculty.nsysu.edu.tw

Length frequencies are essential data for fish stock assessments, particularly for longer-lived species. They are... more Length frequencies are essential data for fish stock assessments, particularly for longer-lived species. They are usually provided by commercial vessels, or by port sampling, observers, or sample-vessel programmes, but each of these has limitations. Collection by sample vessels might be the most balanced way if the data quality is verifiable. We introduce a photograph-based length-measurement approach for sample vessels to photograph fish images with a calibration board, using a regular digital camera to obtain length estimates that can be verified after the images are transformed to reduce errors of perspective distortions. We analyse this approach under ideal conditions, develop a set of objective criteria for choosing acceptable photographs from observers, and compare estimated lengths for bigeye tuna (Thunnus obesus) based on this approach with lengths measured by observers. The criteria can serve as guidelines for photographing: if images are captured following these guidelines, the approach shows the potential for obtaining cheaply a large quantity of length estimates that deviate around 3% (up and down) on average from the actual measurements taken by observers.

Sobre la naturaleza de la fotografía digital

by Pilar Irala Hortal

Deceive Me and Do It Well

by Tomas Ciucelis

Published in Photography '08 magazine, Vilnius, Lithuania.
Translation: Jekaterina Lavrinec.
2008

Deception as the ultimate form of historical truth in photographic representation. The case of the scandal over the... more Deception as the ultimate form of historical truth in photographic representation. The case of the scandal over the photoshopped Iranian missles.

Autoportraits numériques. Un exemple de la médiation technologique du devenir des corps.

by Amparo Lasén

Prochaine publication dans Grandjean, N. et Lobet-Maris, C. (eds.) Corps et Technologies, Bruxelles, Peter Lang

: Les uses et pratiques liés aux technologies numériques font partie aujourd’hui des processus d’incarnation, des... more : Les uses et pratiques liés aux technologies numériques font partie aujourd’hui des processus d’incarnation, des devenirs des corps, de ce qui signifie avoir, acquérir et être un corps. Ces médiations technologiques particulières contribuent doublement à inscrire les corps : d’une part leurs traces sont inscrites dans des dispositifs numériques, et de l’autre ces médiations contribuent à la création d’habitudes, gestes,  perceptions et mouvements qui donnent forme aux corps. Ces médiations, qui font partie des processus de subjectivation et sont étroitement liées aux formes d’affectivité, sont explorées dans le cas particulier de la pratique des autoportraits numériques et leur présence croissante dans le web.

Mots clé : autoportraits, photographie numérique, corps, subjectivités.

The Art of Pointing. On Peirce, Indexicality, and Photographic Images

by Martin Lefebvre

Published in Photography Theory (The Art Seminar, II), James Elkins (Ed.), New York: Routledge, 2007.

This piece appeared in one of James Elkins' Art Seminar series as a commentary on the seminar devoted to photography. This piece appeared in one of James Elkins' Art Seminar series as a commentary on the seminar devoted to photography.

Visioni della brutalità nelle fotografie di rete

by Serge Noiret

in Sauro Lusini (ed. La cultura fotografica in Italia oggi. A 20 anni dalla fondazione di AFT. Rivista di Storia e Fotografia., Prato, Archivio Fotografico Toscano-Comune di Prato, 2007, pp.88-106.

Alcune considerazioni sulla presenza di Fotografie Storiche in Rete in Italia

by Serge Noiret

in Lorenzo Cottignoli (ed.): Scatti di memoria. Dall'archivio fotografico della federazione delle cooperative della Provincia di Ravenna, Ravenna, Longo Editore, 2002, pp.158-177.

La fotografia storica su Internet oggi in Italia

by Serge Noiret

in Contemporanea, IV, n.4, October 2001, pp.803-813

The Reprediction of the Self: Digital Photography, Serendipity and the Mirror to the Future

by Mark Roxburgh

Published in in Thomas, T. (ed) Photo / Not Photo, University of Canberra, 2008

In this essay I will be discussing reality in relation to photographic practice. This has been a much debated and... more In this essay I will be discussing reality in relation to photographic practice. This has been a much debated and contested area and I am not interested in rehashing those debates to any great extent here. On one level I will be confining myself to a fairly simplistic and commonsense understanding of the term, not because I reject the essence of those debates but because, I would assert, the majority of people who take photographs do so unaware of them. For many people, though they are aware of the extent to which photographs can be manipulated, their normal domestic practice of photography revolves around documenting things, places and people that are real to them. In this sense photography and reality are conflated. It must be said however that as an academic and photographer I do not conflate the two and subscribe to Baudrillard’s concept of the simulacra that would position photographs as a kind of de-facto reality. Where I use the terms realism or realist I am not referring to notions of reality, I am specifically referring to photographs in which the content is highly congruent with the subject matter photographed. In making my argument I will firstly concentrate on digital photography as a domestic practice, that does not involve any significant post shooting computer manipulation, and then discuss the implications of this practice on ‘professional’ photography.

Visioni della brutalità nelle fotografie di rete

by Serge Noiret

Published a first version as: "Immagini in rete di un esecuzione: Beit Hanina, Gerusalemme, 8 marzo 2002, ." in Memoria e Ricerca, n. s., n.20, September-December 2005, pp.169-195.

and after, updated with the title "Visioni della brutalità nelle fotografie di rete" published in

Sauro LUSINI (ed.), La cultura fotografica in Italia oggi, Prato, Archivio Fotografico Toscano-Comune di Prato, 2007, 88-106.

“Public History” e “Storia Pubblica” nella Rete

by Serge Noiret

Ricerche storiche. A. XXXIX N. 2-3 (maggio-dicembre 2009) Media e storia edited by Francesco Mineccia & Luigi Tomassini

Presentation in Florence: Presentation in Florence: http://www.polistampa.com/asp/se.asp?id=1010

Abstract: available inside the journal issue

Visual artefacts as boundary objects in participatory research paradigm

by abhigyan singh

Publisher: Journal of Visual Arts Practice, Intellect Ltd.
Publication Date: April 2011

This article is based on the findings of an ethnographic field research conducted at Sudarshan Layout, an urban slum... more This article is based on the findings of an ethnographic field research conducted at Sudarshan Layout, an urban slum in Bangalore, India in February 2009. The research was participatory in nature and was conducted in collaboration with Ambedkar Community Computing Center (AC3), a group consisting of local youth of Sudarshan Layout. Various visual research methods such as a ‘self-documentation’ exercise, involving the creative use of a digital camera, and ‘social map-drawing’ exercises were employed. These methods led to the creation of various visual artefacts such as hand-drawn social maps and digital photographs. In this article, I argue that these visual artefacts (hand-drawn social maps and digital photographs) acted as boundary objects, enabled a dialogue and promoted negotiation of meaning between the participants and me. In the article, I describe how these visual artefacts facilitated the participatory research and assisted in collaboration, communication and cooperation between us.

Constructing DTMs of breached moraine dam complexes (using 'Structure-from-Motion')

by Matt Westoby

Presented at the British Society for Geomorphology Annual Conference ('Extreme Events - shaping the surface of the earth'), University of Liverpool, 28-30th June 2011.

Whilst the availability and affordability of satellite imagery is progressively increasing, the spatial resolution... more Whilst the availability and affordability of satellite imagery is progressively increasing, the spatial resolution which these afford with which to create digital terrain models (DTMs) is coarse in comparison with active, ground-based techniques.  Presently, the majority of methods capable of surveying complex topography, at high resolution, are accompanied by high costs and difficult portability (e.g. Total Station, TLS). Furthermore, the remoteness and inaccessibility of many field sites renders these approaches impractical.

The research presented herein outlines a novel low-cost, close-range terrestrial photogrammetric approach to obtaining data with which to construct 3D models of breached moraine dams in the Nepal Himalaya.

Real Photography

by Damian Sutton

This is an essay in the anthology entitled State of the Real (I.B.Tauris, 2007), co-edited with Ray McKenzie and Susan Brind.

This paper considers the role of the photograph as object and the object-less nature of photography demonstrated by... more This paper considers the role of the photograph as object and the object-less nature of photography demonstrated by its diversity in reproduction – a feature extended by digital technologies. The paper puts into context the opposing views of the photograph-as-object and the photograph-as-representation by beginning with the question: do we not have a real relationship with photography?
Photography criticism has seen various attempts to understand our relationship with the photograph as an object in itself. Most famously discussed by Roland Barthes (1980) as a form of memento mori, studies of the photograph as object have included those in psychology or sociology (Csikszentmihalyi & Rochberg- Holton, 1981), on the archive and history (Tagg, 1988; Sekula, 1989), and recently in anthropology and material culture (Edwards, 2002; Harper 2002). These views present a discussion of the role of embodiment in the photograph of issues for which photography itself is seen as evocative, especially memory and other emotional significance.
Alternatively, the ‘reality’ of the distributive field of photography, in print and reproduction, on slides and as digital files, suggests that the phenomenological object of the photograph is not tied to the corporeal but instead exists as something other than the object, but nonetheless in some way tied to it. Recent calls for criticism to leave the object of “The Photograph” behind (Osborne, 2003) are complemented by the photograph’s contextual part in the wider information networks that give it meaning (Flusser, 1983).
All of this suggests that photography should be understood theoretically as a plane of immanence (Deleuze & Guattari, 1980) to which meaning and objecthood is ‘attracted’, rather than any particular discipline or object in itself. Using Gilles Deleuze’s notions of the virtual and the actual (Deleuze, 1985) the paper will suggest that photography exists as the immanence of a relationship between real and representation.

Digital Photography and Picture Sharing: Redefining the Public/Private Divide

by Amparo Lasén

Co-authored with Edgar Gómez, published in 2009 Knowledge, Technology & Policy, 2 (3): 205- 215

Digital photography is contributing to the
renegotiation of the public and private divide and to
the... more Digital photography is contributing to the
renegotiation of the public and private divide and to
the transformation of privacy and intimacy, especially
with the convergence of digital cameras, mobile
phones, and web sites. This convergence contributes
to the redefinition of public and private and to the
transformation of their boundaries, which have al-
ways been subject to historical and geographical
change. Taking pictures or filming videos of strangers
in public places and showing them in webs like Flickr
or YouTube, or making self-portraits available to
strangers in instant messenger, social network sites, or
photo blogs are becoming a current practice for a
growing number of Internet users. Both are examples
of the intertwining of online and offline practices,
experiences, and meanings that challenge the traditional
concepts of the public and the private. Uses of digital
images play a role in the way people perform being a
stranger and in the way they relate to strangers, online
and offline. The mere claims about the privatization of
the public space or the public disclosure of intimacy do
not account for all these practices, situations, and
attitudes, as they are not a simple translation of
behaviors and codes from one realm to the other.