The technique of laser speckle photography has been developed with the aim of measuring the strain field around the tip of a fast crack. An image processing system to allow automatic point-by-point analysis of a speckle photograph is described. The Young's fringes diffraction pattern, produced by directing a narrow laser beam through the photograph, is digitised and processed by computer. Two algorithms have been developed based on Fourier and Walsh spectral analysis. The system can measure speckle displacements with an accuracy of better than 0.1 μm. A new technique for measuring time-varying displacement fields by multiple exposure of a single photograph is presented. Results are shown from a five-exposure speckle photograph of a cantilever deformed under quasi-static conditions. Extension of the technique to dynamic problems requires a stroboscopic laser light source; one chapter deals with the development of a Q-switched ruby laser for this purpose. Modulation of the cavity losses with a Pockels cell at up to 1 MHz results in a train of short (~50 ns) light pulses at the modulation frequency. Results are presented from the analysis of speckle photographs of cracks in polymethylmethacrylate (PMMA) under quasi-static loading. Three different data analysis methods for estimating the stress intensity factor from the displacement field are proposed and evaluated. Preliminary results from dynamic crack propagation studies are described. The dynamic stress intensity factor is estimated from double exposure speckle photographs of fast cracks in PMMA, recorded with the ruby laser in double pulse mode. The application of the techniques of moire and high speed photography to the study of dynamic fracture is also discussed; results are presented from a sequence of moire photographs recorded at 5 x 10<SUP>5</SUP> frames s<SUP>-1</SUP> . Further topics covered in the dissertation include a theoretical analysis of viscoelastic losses as a function of crack velocity, and strain-to-failure measurements on plastic bonded explosives in the Brazilian test using laser speckle photography.

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The principle aim of this study was to use the concept of image defocus related to feature depth in order to develop a system capable of converting a 2-dimensional greyscale image into a 3-dimensional depth map. An advantage of this concept (known as depth-from-defocus or simply DfD) over techniques such as stereo imaging is that there is no so-called ‘correspondence problem’ where the corresponding location of a feature or landmark point must be identified in each of the stereo images. The majority – and the most successful – of previous researchers in DfD have used some variation of a ‘two-image’ technique in order to separate the contribution of the original scene features from the defocus effect. The best of those have achieved results typically in the range of 1% to 2% error in the accuracy of depth estimation. This thesis presents a single-image method of generating a high-density, highaccuracy depth map via the evaluation of the edge profiles of a projected structured light pattern. A novel technique of moving the projected pattern during the image capture stage allows the development of a 4-dimensional look-up table. This technique offers a solution to one of the last remaining problems in DfD, that of spatial variance. It also uses a technique to remove the dependence of original scene reflectance. The final solution generates a depth map of up to 240,000 spatially invariant depth estimates per scene image, with an accuracy of within ± 0.5%, over a depth range of 10 cm. The depth map is generated in a processing time of approximately 14 seconds once the images are loaded.

The Influence of Photographic Narrative in Healthcare Dialogue is a research project which developed within an interdisciplinary practice-led environment between arts and healthcare. The overall project aimed at employing photographic narrative to explore concepts that support a holistic approach to clinical interactions, for example empathy and reflective practice. The key proposition in this thesis is that communication between a doctor and his patient is enhanced when the medical practitioner recognises the shared narrative that develops as the process of diagnosis and treatment unfolds. From the medical practitioner's perspective, these narratives contribute to empathetic doctoring and this thesis reports on the author's interest in promoting an active sense of the visual narrative expression during the training of medical students. This project was developed in a series of experiments undertaken during a medical photography elective at Newcastle University Medical School (entitled The Camera Never Lies?) and the student's photographic stories uncover a range of attitudes to learning about 'good doctoring' during a conventional training in clinical practices, a process that demand that the students value professional detachment (Coulehan, 2008:56). My research was developed in response to the experience of teaching photographic practices to medical students within this module. In supporting the students' production of photographic artworks I was able to better understand the potential of non-verbal narrative in clinical environments (the types of professional medical contexts in which the students will apply their knowledge after they have graduated) and in medical training (the context into which I had been invited to transfer my knowledge of photographic portraiture in order to enhance the students' sensitivity to visual communication). In this sense, my thesis reports on the progress I have made as both a translator of visual arts ideas and as an artist exploring the narratological nature of taking portrait photographs (based on a range of influences from Jo Spence to Cindy Sherman). Moreover, my research provides an alternative approach to portraiture by producing photographic portraits with a method of renarration. My activities with the medical students were developed as a practice-led research project in which I used my personal experiences of creating sequences of photographic self-portraits to stimulate reflective practices amongst my students. Once they had learnt to make their own reflective portraits I was able to respond to their images with more of my own that interpreted and reflected their narratives back to them. The students clearly gained from this experience and over the past three years I have evolved the process into a teaching method specifically aimed at improving clinical skills. This photo-narratological interaction, and the benefits that the students experienced, became the basis of my research question and my methodology. My interest in finding solutions to the process of applying 're-narration', a concept I adapted from psychoanalysis (Josselson & Lieblich, 1996), to both my arts practice and my medical teaching became the central quest of my project. As with all practice-led research, I saw this exploratory journey as an opportunity for action research and my thesis considers this approach using Winch and Gingell's five stages: situation, concern, intervention, documentation and dissemination (Gingell & Winch, 1999). As a result, I am able to systematically shape my thesis around my entire journey: from the initial, open-ended phase embedded in the arts and health research project at Northumbria University to its later, more focussed period in which I am able to prepare my findings for conferences in the Medical Humanities sector. At this stage, the student projects have become case studies that are conceptualized and investigated within the framework of life narrative research, an interdisciplinary method that is used in sociology, psychoanalysis and anthropology (Czarniawska,2004). The central section of my thesis describes this part of my project in both practical and theoretical terms. All along, my aim has been to use photography as a vehicle for opening new lines of communication between arts and healthcare, two distinct fields of research that stand to gain from being brought into closer relations with one another (see the Wellcome Trust website in support of this claim, available at http://www.wellcome.ac.uk). My conclusion is that the engagement of medical students with photography can facilitate reflective learning and encourage the development of visual skills that many commentators believe is absent in the structure of medical training yet necessary for the practice of good doctoring (Coulehan, 2008:56). The reflective use of photography through re-narration has resulted in the development of photographic narratives by the students which express their understanding of the different facets of the human condition and health in a range of subjects from self-portraiture to patients' health narratives. The photographic works illustrate an ongoing dialogue of trainee doctors within healthcare situations, the professional engagement with their subject of study and also their individual personal development. The medical students who attended the medical photography elective: The Camera Never Lies? developed an in-depth understanding of the concepts of self-reflection, empathy and also engaged with the important role of these concepts in their professional practice. Some medical students used photography to express their preoccupations with health related subjects by engaging with patients on the basis of photographic projects, whereas others engaged directly with their own personal experiences with eating and mental disorders. As a result the students deconstructed medical stereotypes, challenged their own preconceptions of illness and embraced empathy as the essential skill for the performing of good doctoring. The changing attitudes became evident in both the students' photographic work and their final assessment presentations. Additionally, the public exhibitions of the students' work revealed attitudes of a wider healthcare system. Where healthcare staff responded to the students' work in a controversial way, the hospital patients engaged very positively with the students' approach in the photographs. This contribution of photographic re-narration uncovered healthcare attitudes that respond to Coulehan's definition of gooddoctoring. Reflection through re-narration suggests that an empathetic engagement between medical practitioners and patients could result to a more valuable medical practice compared to the traditional professional detachment. In this sense, the doctor-patient empathetic engagement develops in a two-directional way both from the doctor's and patient's perspectives. As a result, the doctors have learnt to use their reflective skills to communicate better with their patients and in turn the patients have become more empathetic towards their doctors. The Influence of Photographic Narrative in Healthcare Dialogue was supported by an AHRC New Collaborations award hosted by Northumbria Healthcare NHS Foundation Trust and Northumbria University.

In this thesis, I establish and explore the role of phenology in understanding the rapidly changing environment of a subarctic peatland. First, I demonstrate how digital repeat photography can be used to characterize and differentiate distinct plant communities using two years of images. Each habitat is composed of different plant functional groups, promoting the individualistic approach to characterization that near-earth remote sensing tools can provide. The camera-product Relative Greenness successfully characterized interannual variability in seasonal growth for each habitat type. Across habitats, there was a direct relationship between advancement of spring onset and active season growth though this overall pattern showed habitat-specific variance. The camera images were also useful in characterizing the flowering phenology of an ​eriophorum​-rich fen habitat, for which a metric named Intensity was created. These results suggest that employment of phenology cameras in highly heterogeneous subarctic environments is a robust method to characterize phenology on a habitat to species scale. Next, I explored the role that this phenology product has in modeling Net Ecosystem Exchange (NEE) also measured at the field site. I hypothesized that the explanatory power of the phenology index, which is conceptually tied to a measure of photosynthetic capacity, would be tightly linked to the timescale it was used for: At sub-daily timescales, environmental forces would dominate, though when averaged over days to weekly scales, the biology represented through the camera index would be more influential. I show that at multiple time scales the environmental factors outperform the camera index when modeling NEE. Together, these studies begin to explore the applicability of phenology camera systems in subarctic environments.

QC 351 A7 no. 60 / The atmospheric transmission and airlight in three spectral bands as a function of an angle off nadir were calculated from radiometric measurements with cameras and film for a particular solar irradiance and atmosphere; the sun zenith angle was 49 °, the airpaths were from 15,000 ft m.s.l. to the surface at 1,900 ft on a clear day in Tucson, Arizona, and the azimuth was into the sun. The three spectral bands had peak transmissions at 430 nm (blue), 530 nm (green), and 800 nm (infrared). The statistics derived from numerous measurements show that a standard deviation of 2% can be attained in the relative radiances read out of multiband photography obtained with calibrated cameras and processed with carefully controlled sensitometry. In the blue and green bands, the atmospheric effect on contrast as a function of an angle off nadir became statistically noticeable at about 35° and 50 °, respectively. The standard deviations of the relative radiances measured in the blue and green bands were 3% and 2 %, respectively. The effect in the infrared band probably became significant at even larger angles; greater inaccuracy in the infrared band data precludes a more definitive statement. Also presented is a solution for an optimum ratio of playback lamp luminances for false color recombinations in two bands.

I was born the only American in my West Indian, Guyanese family. My culture played a large part in how I was brought up, and in turn, shaped the person and artist I have become. In my work, I like for my viewers to get a personal feel for what it is like to be West Indian American. My work is a cultural record of people, places, and things. I capture small, special moments because I know that they will never be recreated. My camera’s viewfinder has always been filtered through my eye as a child of immigrant parents. I use photography as my first step in creating and recording ordinary, everyday things. Photographs are captured where I feel most American eyes would by-pass or overlook their importance. However, my work must also involve my hand. Therefore, through my mark making, whether I am drawing, painting, collaging, stitching or using software, I add and subtract from my original photos. By manipulating my images, I change and emphasize a single, fleeting moment into something permanent and significant.

Lightness and darkness pervades much of my work which is visible in images of abandoned, secluded spaces. Light symbolizes hope and joy. It can also reference the spiritual connotation of new life as well as the end of life. The physical movement of light, its ephemeral quality, and its reflectivity is the deciding factor in my choice for using a camera without a lens and using traditional painting techniques. In my photographic mixed media work, I am drawn to the unique qualities of the pinhole camera, the exposure of light on the surface of film yields imagery that blurs the line between the familiar and the ethereal. Exposures from a pinhole camera materialize over time, perhaps seconds, perhaps minutes. There is no viewfinder to preview the image, which makes capturing an image pleasingly accidental. In my oil painting, I use photographic references and a limited palette. Much like my photographs, I create areas of light juxtaposed against deep shadow. The processes of using overlapping layers of transparent glazes over a warm-toned ground are used to achieve this chiaroscuro effect. By using these approaches, a sense of the dramatic is conveyed sometimes in contrast to the quiet nature of the subject.

Society and popular culture present their ideas of perfection through the media. I wish to reinvent these standards in my art, to show the beauty of the ordinary and the grace of the flawed. Beauty, by definition, is that which gives intense aesthetic pleasure. I think that aesthetic pleasure can be found in the commonplace and I use aspects of cropping, perspective, and scale to show these everyday items as extraordinary. I want people to realize the loveliness of a street lamp, the sensuality of a smile, or the poetry of an elbow. This is the underlying theme that runs through all of my work. The evolution of the methods used to create this beauty is also important. Cropping images and adding textures to my supports has shaped my approach to realism. It has been quite a journey.