Academic literature on the topic 'Early colour photographic processes'

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Journal articles on the topic "Early colour photographic processes"

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End, Albert, and Matthias Gamer. "Task instructions can accelerate the early preference for social features in naturalistic scenes." Royal Society Open Science 6, no. 3 (March 2019): 180596. http://dx.doi.org/10.1098/rsos.180596.

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Previous research demonstrated that humans rapidly and reflexively prioritize social features (especially heads and faces) irrespective of their physical saliency when freely viewing naturalistic scenes. In the current study, we investigated whether this preference for social elements already occurs maximally fast during free exploration or whether it is possible to additionally accelerate it by means of top-down instructions. To examine this question, we presented participants with colour photographs of naturalistic scenes containing social features (e.g. heads and bodies) while recording their eye movements. For half of the stimuli, observers were instructed to freely view the images; for the other half of the stimuli, their task was to spot depicted people as fast as possible. We replicated that social elements (especially heads) were rapidly preferred over physically salient image parts. Moreover, we found the orienting towards social elements to be additionally enhanced and accelerated when participants were instructed to detect people quickly. Importantly, this effect was strongest for heads and already evident at the very first fixation. Thus, the present study not only corroborates that the prioritization of social features in naturalistic scenes partially relies on reflexive processes, but also demonstrates that these mechanisms can be additionally accelerated by top-down instructions.
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Fraser, Kathryn. "The Photographic Insane." Cinémas 9, no. 1 (October 26, 2007): 139–51. http://dx.doi.org/10.7202/024777ar.

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ABSTRACT Bazin's famous essay touting the photograph's identicality with its subject was precedented by photography's early relation to empirical investigation in the human sciences (the psychiatry). Contrary to this, what this author wishes to reinforce in this paper is that perception is constructed and integrally bound up with conceptual processes. This paper thus constitutes a short examination of what this author calls the "Photographic Insane," and illustrates how images of madness use, and require for their interpretation, a particular, and culturally shared "schematic" framework.
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Mollon, J. D. "Colour Perception 1978–1997." Perception 26, no. 1_suppl (August 1997): 274. http://dx.doi.org/10.1068/v970021.

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In the past twenty years, the spectral sensitivities of the three types of cone have been established with some certainty: direct measurements by microspectrophotometry and electrophysiology are in fair agreement with psychophysical estimates. Particularly significant was the publication of DNA sequences for the four opsins of the human eye, by Jeremy Nathans and colleagues in 1986. This work was soon to transform the understanding of retinitis pigmentosa and other retinal dystrophies, and it has given many insights into the evolution of colour vision; but, curiously, the explanations of dichromacy and anomalous trichromacy have not proved as straightforward as we all expected in 1986. What is clear, however, is that normal colour vision exhibits a genetic polymorphism: much of the intersubject variance in colour matches can be traced to differences in the amino-acid sequence of the opsins for the long-wave and middle-wave cone pigments. The last two decades have seen a major change in the status of opponent processes. In the 1970s it was still common for professors to tell undergraduates that the Young - Helmholtz theory of colour vision held at the receptor level and the Hering theory at the level of the retinal ganglion cells. It is now clear that the chromatically antagonistic processes revealed electrophysiologically and psychophysically in the early visual system do not correspond to the red - green and yellow - blue processes that Hering postulated on the basis of phenomenological observations. The existence of four unique hues is today one of the unexplained mysteries of colour science. In one salient respect, research in colour vision has been changed by instrumental advances. Computer-controlled monitors (though offering splendid pitfalls to the unwary) have allowed the study of spatially and temporally complex chromatic displays, notably in the field of colour constancy. Most recently there has been interest in the chromatic statistics of natural scenes: how well is the visual system matched to the statistics of the world and can it adapt to the gamut of chromaticities present in a given scene?
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Pierce, Kathleen. "Photograph as Skin, Skin as Wax: Indexicality and the Visualisation of Syphilis in Fin-de-Siècle France The William Bynum Prize Essay." Medical History 64, no. 1 (December 19, 2019): 116–41. http://dx.doi.org/10.1017/mdh.2019.79.

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In early twentieth-century France, syphilis and its controversial status as a hereditary disease reigned as a chief concern for physicians and public health officials. As syphilis primarily presented visually on the surface of the skin, its study fell within the realms of both dermatologists and venereologists, who relied heavily on visual evidence in their detection, diagnosis, and treatment of the disease. Thus, in educational textbooks, atlases, and medical models, accurately reproducing the visible signposts of syphilis – the colour, texture, and patterns of primary chancres or secondary rashes – was of preeminent importance. Photography, with its potential claims to mechanical objectivity, would seem to provide the logical tool for such representations.Yet photography’s relationship to syphilographie warrants further unpacking. Despite the rise of a desire for mechanical objectivity charted in the late nineteenth century, artist-produced, three-dimensional, wax-cast moulages coexisted with photographs as significant educational tools for dermatologists; at times, these models were further mediated through photographic reproduction in texts. Additionally, the rise of phototherapy complicated this relationship by fostering the clinical equation of the light-sensitive photographic plate with the patient’s skin, which became the photographic record of disease and successful treatment. This paper explores these complexities to delineate a more nuanced understanding of objectivity vis-à-vis photography and syphilis. Rather than a desire to produce an unbiased image, fin-de-siècle dermatologists marshalled the photographic to exploit the verbal and visual rhetoric of objectivity, authority, and persuasion inextricably linked to culturally constructed understandings of the photograph. This rhetoric was often couched in the Peircean concept of indexicality, which physicians formulated through the language of witness, testimony, and direct connection.
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Kazakevych, Gennadii. "Memory Factories: Professional Photography in Kyiv, 1850-1918." Text and Image: Essential Problems in Art History, no. 1 (2020): 82–101. http://dx.doi.org/10.17721/2519-4801.2020.1.06.

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The article deals with the early history of photographic industry in Kyiv as a complex cultural phenomenon. Special attention is focused on the portrait photography as a ‘technology of memory’. It involves methods of social history of art, prosopography and visual anthropology. The study is based on the wide scope of archival documents, including the correspondence of publishing facilities inspector, who supervised the photographic activity in Kyiv from 1888 to 1909. By the early 20th century, making, collecting, displaying and exchanging the photographic portraits became an important memorial practice for townspeople throughout the world. In the pre-WWI Kyiv dozens of ateliers produced photographic portraits in large quantities. While the urbanization and economic growth boosted migration activity and washed out traditional family and neighborhood networks, the photography provided an instrument for maintaining emotional connections between people. The author emphasizes the role of a professional photographer who acted as a maker of ‘memory artifacts’ for individuals and families and, therefore, established aesthetic standards for their private visual archives. It is stated that the professional photography played a noticeable role in modernization and westernization of Kyiv. With its relatively low barrier to entry, it provided a professionalization opportunity for women, representatives of the lower social classes or discriminated ethnic groups (such as Poles after the January Insurrection, and Jews). While working in a competitive environment, photographers had to adopt new technologies, improve business processes and increase their own educational level. At the same time, their artistic freedom was rather limited. The style of photographic portrait was inherited from the Eighteen and Nineteen-century academic art, so it is usually hard to distinguish photographic portraits made in Kyiv or in any other European city of that period. Body language of models, their clothing and personal adornments as well as studio decorations and accessories aimed to construct the image of successful individuals, faithful friends, closely tied family members with their own strictly defined social roles etc. The old-fashioned style of the early twentieth century portraiture shaped the visual aesthetics of photographic portrait that was noticeable enough even several decades later.
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Dzhanfezova, Tanya, Chris Doherty, and Nedko Elenski. "UNPACKING THE EARLY NEOLITHIC?" Samara Journal of Science 4, no. 3 (September 1, 2015): 63–71. http://dx.doi.org/10.17816/snv20153205.

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The preliminary analysis of Early Neolithic pottery from North Central Bulgaria, and the site of Dzhulyunitsa specifically, yielded surprising results which affect a number of aspects related to the study of the Neolithisation processes. Not all characteristic features traditionally considered as key signal of the Neolithisation processes were confirmed by our mineralogical and chemical analysis. A number of specifics related to the presence of engobe for instance, indicate a considerably more complex picture. In some cases the observations show no additional slip, just a simple burnish of the brownish ware, whereas in others a true slip covers both the inner and the outer surface of the vessels (white or cream-slip ware). With regard to the red engobe specifically, the majority of studied fragments actually have just red-colour surface that results from the oxidation or the rubbing of ochre, and not from the addition of a true slip. These observations raise the following question: do we actually compare same technological approaches, traditionally seen as signal for the spread of the Neolithic way of life? Furthermore, as regards the provenance of the vessels, materials expected to have local origin proved to be imported whereas others, seen as more specific and coming from distant territories were actually made on the spot by local row-materials. Even at this stage the preliminary results do not confirm some of the traditional views on this early material, raise a series of new questions and represent a ground for further interpretations and discussions regarding an eventual fragility of some models suggested for the Neolithisation processes in this part of South-East Europe.
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Rogge, Corina E., and Anikó Bezur. "An Investigation into the Creation, Stability, and X-ray Fluorescence Analysis of Early Photographic Processes: An Upper-Level Undergraduate Laboratory." Journal of Chemical Education 89, no. 3 (July 8, 2011): 397–400. http://dx.doi.org/10.1021/ed101185d.

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Lieser, J. L., M. A. J. Curran, A. R. Bowie, A. T. Davidson, S. J. Doust, A. D. Fraser, B. K. Galton-Fenzi, et al. "Antarctic slush-ice algal accumulation not quantified through conventional satellite imagery: Beware the ice of March." Cryosphere Discussions 9, no. 6 (November 11, 2015): 6187–222. http://dx.doi.org/10.5194/tcd-9-6187-2015.

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Abstract. Our current knowledge of broad-scale patterns of primary production in the Southern Ocean is derived from satellite ocean-colour estimates of chlorophyll a (Chl a) in the open ocean, typically in spring-summer. Here, we provide evidence that large-scale intra-ice phytoplankton surface aggregation occur off the coast of Antarctica during austral autumn, and that these "blooms" are largely undetected in satellite ocean-colour time series (which mask the ice-covered ocean). We present an analysis of (i) true-colour (visible) satellite imagery in combination with (ii) conventional ocean-colour data, and (iii) direct sampling from a research vessel, to identify and characterise a large-scale intra-ice algal occurrence off the coast of East Antarctica in early autumn (March) 2012. We also present evidence of these autumn "blooms" in other regions (for example, Princess Astrid Coast in 2012) and other years (for example, Terra Nova Bay in 2015) implying regular and widespread occurrence of these phenomena. The occurrence of such undetected algal accumulations implies that the magnitude of primary production in the Southern Ocean is currently underestimated.
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Gariépy, C., B. Ghaleb, C. Hillaire-Marcel, A. Mucci, and S. Vallières. "Early diagenetic processes in Labrador Sea sediments: uranium-isotope geochemistry." Canadian Journal of Earth Sciences 31, no. 1 (January 1, 1994): 28–37. http://dx.doi.org/10.1139/e94-004.

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The concentration and isotopic composition of U dissolved in pore waters from hemipelagic sediments of the Labrador Sea were determined by thermal ionization mass spectrometry in two 30 cm long box cores. The present fluxes of seawater U that diffuses across the sediment–seawater interface are on the order of 2–4 μg/(cm2∙ka). This diffusion imposes decreasing gradients of dissolved U downwards, but the U concentration in pore waters immediately below the surface is much lower than that of open-ocean seawater. This is a primary feature that cannot be explained by carbonate precipitation due to decompression during core retrieval. More likely, it reflects the presence of a stagnant benthic boundary layer above the sediment–water interface, in which molecular diffusion of U is slower than in the overlying turbulently mixed seawater, and (or) of microzones near the interface where U is bioaccumulated. Uranium is adsorbed at depths onto the solid phase in response to changes in the redox conditions within the sediments. In the Labrador Sea, this occurs at the onset of iron reduction and corresponds to a colour transition from brown to grey. Adsorption of U is sufficiently large to alter the initial content and the isotopic composition of U in the detrital component. Accumulation of authigenic U on the solid phase does not proceed at a steady state. This is due to the uneven burial rates of organic matter, which is essential to the establishment of redox conditions appropriate for U reduction, and concomitant stepwise displacement of the redox fronts. This indicates that discrete periods of enhanced primary productivity recurred over the last millenium in the Labrador Sea, inducing U fluxes to the sediments greater than they are now. Measured pore-water U concentrations are greater than the overlying seawater at depth in the cores, despite the fact that none of the conditions necessary to release U under reducing conditions are present in the sediments. More likely, U-bearing particles < 0.45 μm were transferred with the solution phase through the filtering device, artificially increasing the pore-water U content.
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Oliva, A., and P. G. Schyns. "Diagnostic Colours Influence Speeded Scene Recognition." Perception 25, no. 1_suppl (August 1996): 114. http://dx.doi.org/10.1068/v96l1007.

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A critical aspect of early visual processes is to extract shape data for matching against memory representations for recognition. Many theories of recognition assume that this is achieved by luminance information. However, psychophysical studies have revealed that colour is being used by low-level visual modules such as motion, stereopsis, texture, and 2-D shapes. Should colour really be discarded from theories of recognition? Here we present two studies which seek to throw light on the role of chromatic information for the recognition of real scene pictures. We used three versions of scene pictures (gray levels, normally coloured and abnormally coloured) coming from two broad categories. In the first category, colour was diagnostic of the category (eg beach, forest, and valley). In the second category colour was not diagnostic (eg city, road, and room). In the second category colour was not diagnostic (eg city, road, and room). Results revealed that chromatic information is being registered and facilitates recognition even after a 30 ms exposure to the scene stimuli. However, influences of colour on speeded categorisations were only observed with the colour-diagnostic categories. No influence of colour was observed with the other categories. A similar pattern of results was observed with 120 ms exposure. However, there was an interference of the wrong colour on recognition in colour-diagnostic categories. In sum, colour, when it is diagnostic of the category, influences speeded scene recognition.
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Dissertations / Theses on the topic "Early colour photographic processes"

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Fonseca, Amanda Ferreira Branco da. "Câmera e pincel : grafismos corporais e processos fotográficos /." Universidade Estadual Paulista (UNESP), 2017. http://hdl.handle.net/11449/153424.

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A presente dissertação aborda minha produção no campo da fotografia expandida, em ensaios que unem pintura corporal e processos fotográficos históricos. Também inclui o desenvolvimento da série Religare, que é o corpus resultante dessa pesquisa de mestrado. Trata-se de um ensaio realizado com a própria artista como modelo da pintura corporal, e revelado com a técnica goma bicromatada sobre madeira, em grandes dimensões (algumas medindo cerca de 88 x 150 cm). Tanto no caso dos ensaios anteriores a essa dissertação, quanto em Religare, os processos são marcados por experimentação e desenvolvimento de técnicas, em geral híbridas, envolvendo: desenho manual dos grafismos corporais, captação digital das imagens, processamento digital, impressão em transparências e revelação das imagens usando processos fotográficos artesanais (marrom Van Dyck, cianotipia e goma bicromatada). Buscando referências na prática da pintura corporal realizada por diversas etnias indígenas, e em posturas do Yoga, esses ensaios desenvolvem uma poética de resgate da vivência do Sagrado, que parece distante na vida urbana contemporânea. O corpo é o instrumento para isso, é o estar aqui e agora. Nos ensaios apresentados, o corpo ganha destaque, conferido pela pintura corporal, pela referência a posturas de Yoga, e pelo trabalho artesanal, também presente na pintura corporal e nos processos fotográficos. Também há destaque para o “corpo” da fotografia, a materialidade do meio, tendo como suportes o papel, o tecido e a madeira.
The present dissertation approaches my production in expanded photography, in photographic essays that unite body painting and early photographic processes. It also includes the development of Religare, essay that is this master's research resulting corpus. The artist herself is model for body painting, and the images are printed in large sizes (some about 88 x 150 cm) using gum bichromate on wood. In previous essays, as in Religare, the processes are based on technical experiment and development, which are usually hybrids, including: handmade drawing of body painting, digital capture of images, digital processing, digital negatives printing and photography printing using early photographic processes (Van Dyck brown, cyanotype and gum bichromate). Seeking references in the indigenous practice of body painting and Yoga poses, those essays develop a Sacred experience rescue poetics, due to this experience seeming distant from contemporaneous urban life. The body is the instrument for this experience, it's "being here and now". At the presented essays, the body is highlighted by the body painting, the reference to yoga poses, and by handcraft process, which includes body painting and early photographic processes. Also the photography "body" is highlighted, the media materiality, embodied by paper, fabric and wood.
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Books on the topic "Early colour photographic processes"

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Seaver Center for Western History Research (Natural History Museum of Los Angeles County), Natural History Museum of Los Angeles County, and Fisher Gallery (University of Southern California), eds. Lost & found: Rediscovering early photographic processes : American Case Art Collection from the Seaver Center for Western History Research, Natural History Museum of Los Angeles County : Fisher Gallery, University of Southern California, March 7-April 21, 2002. Los Angeles, CA: Fisher Gallery, University of Southern California, 2001.

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Centre national de la photographie (France), ed. Early color photography. New York: Pantheon Books, 1986.

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Hawarth-Booth, Mark, and Brian Coe. A Guide to Early Photographic Processes. Hyperion Books, 1989.

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Searle, Mike. Colliding Continents. Oxford University Press, 2013. http://dx.doi.org/10.1093/oso/9780199653003.001.0001.

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The Himalaya is the greatest mountain range on Earth: the highest, longest, youngest, the most tectonically active, and the most spectacular of all. Unimaginable geological forces created these spectacular peaks. Indeed, the crash of the Indian plate into Asia is the biggest known collision in geological history, giving birth to the Himalaya and Karakoram, one of the most remote and savage places on Earth. In this beautifully illustrated book, featuring spectacular color photographs throughout, one of the most experienced field geologists of our time presents a rich account of the geological forces that were involved in creating these monumental ranges. Over three decades, Mike Searle has transformed our understanding of this vast region. To gather his vital geological evidence, he has had to deploy his superb skills as a mountaineer, spending weeks at time in remote and dangerous locations. Searle weaves his own first-hand tales of discovery with an engaging explanation of the processes that formed these impressive peaks. His narrative roughly follows his career, from his early studies in the north west Himalaya of Ladakh, Zanskar and Kashmir, through several expeditions to the Karakoram ranges (including climbs on K2, Masherbrum, and the Trango Towers, and the crossing of Snow Lake, the world's largest ice cap outside polar regions), to his later explorations around Everest, Makalu, Sikkim and in Tibet and South East Asia. The book offers a fascinating first-hand account of a major geologist at work-the arduous labor, the eureka moments, and the days of sheer beauty, such as his trek to Kathmandu, over seven days through magnificent rhododendron forests ablaze in pinks, reds and white and through patches of bamboo jungle with hanging mosses. Filled with satellite images, aerial views, and the author's own photographs of expeditions, Colliding Continents offers a vivid account of the origins and present state of the greatest mountain range on Earth.
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Book chapters on the topic "Early colour photographic processes"

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Jørgensen, Anne Mette. "A Gentle Gaze on the Colony: Jette Bang’s Documentary Filming in Greenland 1938–9." In Films on Ice. Edinburgh University Press, 2015. http://dx.doi.org/10.3366/edinburgh/9780748694174.003.0018.

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This chapter discusses one of few women documentary filmmakers of the Arctic, Danish Jette Bang. A prolific photographer and filmmaker in Greenland throughout her career, Jørgensen shows how the early color film Inuit (1940) was nimbly shot and cinematographically deliberate. Made for the 1940 International Polar Year, the film and accompanying photo book created substantial media coverage when it premiered in Copenhagen. Bang’s later films, including her depictions of a changing Greenlandic society in the 1950s and 60s, this chapter argues, were made with the intent to both document Greenlandic life in the post-war era and as a testament to Denmark’s benevolent colonial rule of Greenland. Bang’s films thereby showcase the welfare state and industrial modernization processes imported Greenland, while maintaining an interest in ‘traditional’ practices and customs.
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Quattrochi, Dale A., and Stephen J. Walsh. "Remote Sensing." In Geography in America at the Dawn of the 21st Century. Oxford University Press, 2004. http://dx.doi.org/10.1093/oso/9780198233923.003.0037.

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As noted in the first edition of Geography in America, the term “remote sensing” was coined in the early 1960s by geographers to describe the process of obtaining data by use of both photographic and nonphotographic instruments (Gaile and Wilmot 1989: 46). Although this is still a working definition today, a more explicit and updated definition as it relates to geography can be phrased as: “remote sensing is the science, art, and technology of identifying, characterizing, measuring, and mapping of Earth surface, and near Earth surface phenomena from some position above using photographic or nonphotographic instruments.” Both patterns and processes may be the object of investigation using remote sensing data. The science dimension of geographic remote sensing is rooted in the fact that: (1) it is dealing with primary data, wherein the investigator must have an understanding of the environmental phenomena under scrutiny, and (2) the investigator must understand something of the physics of the energy involved in the sensing instrument and the atmospheric pathway through which the energy passes from the energy source, to the Earth object, to the sensor. The art dimension of geographic remote sensing has to do with the creative ways that the scientific interpretations are presented for visualization and measurement. The technological dimension of geographic remote sensing has to do with the constantly evolving hardware, software, and algorithmic manipulation and modeling involved in the collection, processing, and interpreting of data regarding the Earth phenomena under investigation. It is the rapidly advancing combination of these three dimensions over recent decades that has brought remote sensing to be a vibrant and dynamic part of the discipline of geography today. We wish not to dwell at length on the historical aspects of remote sensing as it relates to geography. This has been done quite adequately in the first edition of Geography in America as well as in other publications, such as the American Society of Photogrammetry and Remote Sensing (ASPRS) Manual of Remote Sensing series (e.g. Colwell 1983), that is now going through a third edition and complete update, and is being presented as a compendium of individual volumes that deal with specific aspects of remote sensing science.
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Conference papers on the topic "Early colour photographic processes"

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de Raad, Jan A. "Reliability of Mechanised UT Systems to Inspect Girth Welds During Pipeline Construction." In 1998 2nd International Pipeline Conference. American Society of Mechanical Engineers, 1998. http://dx.doi.org/10.1115/ipc1998-2073.

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As an alternative to radiography, a field-proven mechanized ultrasonic inspection system is discussed. Called Rotoscan, this system has been developed for inspection of girth welds during construction of long-distance pipelines, both on- and offshore. It is characterized by high inspection speed and instant recording of results. Unlike prevailing radiography, it provides immediate feedback to the welders. Recent technical improvements in flaw sizing and recording have allowed the application of rejection/acceptance criteria for weld defects based on fracture mechanics principles. The development and actual use of such modern acceptance criteria, particularly in Canada, supported the introduction of mechanised ultrasonic inspection. World wide applications proved that, contrary to expectations, ultrasonic inspection does not lead to higher weld repair rates than radiography does. Between early 1989 and now, over 5.000 km of pipeline (300.000 welds) were inspected with Rotoscan and its reliability proven. The introduction of colour enhanced transit distance “C-scan mapping”, producing a coherent picture based on the signal’s transit distance, enabled the system to cope with most existing ultrasonic procedures and acceptance criteria, because of its capability to detect and quantify volumetric defects. Moreover, the integrated simultaneous Time Of Flight Diffraction (TOFD) function enables through-thickness sizing of defect. The present system is capable of achieving a high Probability Of Detection (POD) together with a low False Call Rate (FCR). In the meantime, Rotoscan has been qualified in various countries, for different customers and for a variety of weld processes, pipe diameters and wall thicknesses. Because of its features, the now mature system has demonstrated its capabilities also for use on lay barges as an alternative to high-speed radiography.
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