扫描全景方法在现场照相中的应用与分析

回转连续拍照法是现场照相常用的一种方法。但这种方法对拍摄和图像处理技术要求高,难以推广和普及。扫描全景方法具有操作简单、成像质量好、成功率高的特点。试验表明,在拍摄距离不变或空间大小受到限制的情况下,为了扩大现场的取景范围,与广角镜头和超广角镜头相比,采用扫描全景方法拍照是一种最佳的选择。因此,它可以完全取代回转连续拍照法,非常适用于现场方位照相和现场概貌照相。     

Nazlı's photographic games: Said and art history in a contrapuntal mode

ABSTRACT

Through a focus on photographic portraits commissioned in the late nineteenth century by the Ottoman-Egyptian Princess Nazl? Han?m, Roberts analyses the ways they tested Ottoman and western conventions. An examination of Nazl?'s strategic engagement with photography in this period positions her within the often-separated domains of Egyptian nationalism, Ottoman political reform, western Orientalist art and a proto-feminist moment of Egyptian women's history. One of the striking things about the Nazl? portraits is their transgressive inventiveness. This is transgression as Edward Said defines it, with an emphasis on crossing boundaries, testing and challenging limits, and cutting across expectations. Nazl?'s inventiveness is apparent through her canny experimentation with the codes of portrait photography and the ways she deploys her portraits as tokens of exchange within her culture and with her European interlocutors. Roberts argues that Nazl? Han?m's use of photography operates in a contrapuntal mode in the Saidean sense of a simultaneity of voices that sound against, as well as with, each other. Over the last three decades Said's writings have provided a crucial methodological framework for the critique of western Orientalist visual culture. Recently art historians have repositioned this corpus of western imagery in relation to art by practitioners from the region and addressed cultural exchanges. Said's seminal text Orientalism has been pivotal within these debates. Yet it is not so much this landmark book, but rather Said's writings on music, in which we can find an alternative approach to cross-cultural exchange. By transposing this model into the domain of art history, Roberts engages with his notion of reading contrapuntally. Said was interested in the broader applicability of this term, although its potential as an interpretive model for the visual arts remains unexamined. Through this case study of Nazl? Han?m's photographs, Roberts reassesses the value of Said's writings on music for understanding nineteenth-century visual culture.     

The Truths/Fictions/Traumas of Marikana: Exploring Violence and Trauma in Three Films,The Marikana Massacre: Through The Lens (2013), Miners Shot Down (2014), and Night is Coming: A Threnody for the Victims of Marikana (2014)

ABSTRACT

By exploring three films that centre on the Marikana strikes and killings of 2012, I seek to examine both the representations of violence as trauma, and the trauma of representing violence, within the context of visual, cinematic texts. I position Marikana, and the trauma of Marikana, as both a highly significant moment, and also as representative of deeper social and political traumas and injustices. I ask whether and how these films create a narrative context for this pivotal moment in South African history. I also question the effects of cinematic style and genre in the depictions of trauma and violence. The institutional context in which each film originated and developed is important, and I argue that the audience's expectations of the genre of documentary film also play a significant role in the way in which the films process trauma. I situate my paper in conversation with previous articles by Lucy Graham and Helene Strauss among others, that deal with cinematic portrayals of Marikana. By examining the selected films alongside each other, and through the lens of Decolonial Trauma Studies, I hope to elucidate the ways in which these South African films deal with and work through trauma.     

The Spectre of Crime: Photography,Law and Ethics

A grainy series of surveillance photographs was tendered into evidence at the trial of a young Aboriginal man accused of robbing a bank. Two police officers testified that they recognised him from the photographs. On appeal to the High Court of Australia, the judges thought that the hooded bandit in the image looked like the spectre from Hamlet. This article uses the discourse of “spectrality” to explore the consequences for law and ethics when haunted by the transgressive image. It examines the confrontation between the foundational illegality of the Australian nation, and the indigenous man who is accused of a crime against property.     

Estimating the Skull‐to‐Camera Distance from Facial Photographs for Craniofacial Superimposition

The overlay of a skull and a face image for identification purposes requires similar subject‐to‐camera distances (SCD) to be used at both photographic sessions so that differences in perspective do not compromise the anatomical comparisons. As the facial photograph is the reference standard, it is crucial to determine its SCD first and apply this value to photography of the skull. So far, such a method for estimating the SCD has been elusive (some say impossible), compromising the technical validity of the superimposition procedure. This paper tests the feasibility of using the palpebral fissure length and a well‐established photographic algorithm to accurately estimate the SCD from the facial photograph. Recordings at known SCD across a 1–10 m range (repeated under two test conditions) demonstrate that the newly formulated method works: a mean SCD estimation error of 7% that translates into <1% perspective distortion error between estimated and actual conditions.     

Diary of an astronaut: examination of the remains of the late Israeli astronaut Colonel Ilan Ramon's Crew Notebook recovered after the loss of NASA's space shuttle Columbia

Two months after the fatal re-entering into the Earth's atmosphere of Columbia flight STS-107, the remains of Israeli astronaut Colonel Ilan Ramon's Crew Notebook were found strewn in a field in San Augustine County, TX. The random pile of papers was found to have survived the calamity of the Shuttle's disintegration remarkably well. Most of the papers recovered were torn and/or washed out to varying degrees but only mildly charred around the edges. The sheets of paper could be categorized into four groups: Group I: eight sides of paper written while in space in black ink and in pencil--Ramon's personal diary; the writing on these eight sides of paper survived well and is only missing where the pages were torn. Small fragments found in the field were physically matched to holes in the pages thus locating their original positions in the text. Group II: six sides of technical preparation notes written by Ramon before the mission. The writing on these pages was washed out entirely, but much of it was visualized using infrared luminescence. Group III: eight sides of personal notes prepared by Ramon before the mission written in blue ink. The writing on these pages was barely visible to the naked eye and not visualized by infrared luminescence, but was made largely legible by digital enhancement imaging. Group IV: a few sides of printed technical information. These pages were mostly intact and were not examined at length as they contained standard printed material. After completion of examinations at the Questioned Document Laboratory of the Israel Police, the diary was transferred to the Paper Conservation Department of the Israel Museum for preservation and strengthening treatments.     

近红外照相显现深色衣料上血迹的实验研究

目的运用近红外反射照相技术,显现深色衣料上的全血及稀释血迹。方法取单个体人全血,用纯净水分别以1∶4、1∶8、1∶16、1∶32比例稀释,并立即将稀释血及全血分别滴落在10种组份共21块深色衣料上,使其自然干燥形成血迹,用普通数码相机及专业红外数码相机,分别对血迹进行拍照获取彩色图像及红外黑白图像。结果红外照相显现血迹优于彩色图像;不同衣料相同浓度稀释血迹的红外图像存在差异;相同衣料不同浓度血迹的红外图像亦有所不同。结论近红外红外照相可以很好地显现深色衣料上的血迹,血迹的红外图像形状有助于判断是否为稀释血液所形成;血液浓度对红外显现结果的影响较大。     

现场摄影图片资料在案件侦破中的应用价值研究

案件现场摄影是案件现场勘查的一项工作内容,是固定现场客观状态的必经程序。案件现场摄影图片资料,是案件现场记录的重要组成部分,与现场笔录、现场绘图相互补充、相互印证。正确认识现场摄影图片资料的价值,有助于在案件侦查与调查、证据保全与搜集、法庭调查与审判等各个诉讼环节上,发挥案件现场摄影图片资料应有的重要作用。     

高速瞬间摄影在物证检验中的应用实验

目的采用声、光、电瞬间感应触发的高速闪光成像装置,以普通数码相机拍摄物证瞬间变化形态,提高物证检验的有效性、客观性;方法研制专用摄影装置,包括触发装置、延时器和超高速闪光灯等组件。进行物证瞬间状态摄影实验,研究运动物体瞬间形态的拍照技术方法;结果本实验装置原理简单、有效。最高记录瞬间成像速度小于0.5μm。可以用于常规物证瞬间变化的成像摄影记录。     

The Effects of High Dynamic Range on Fingerprint Images Processed by Photoshop

High dynamic range (HDR) imaging is a function that combines five images with different exposures into a single image. This technique may provide fine ridge details of fingerprint images for forensic latent fingerprint examination. Therefore, viewing fingerprints under optimal conditions is of paramount importance. This paper analyzes HDR and non‐HDR photos by using the Michelson contrast formula. The Michelson formula will provide a measurement to determine whether better contrast between the background and print can be achieved using the HDR function and if the background color affects the quality of the images. Two hypothesis were tested: (i) the HDR image provides more details of fingerprints with a better tone, greater clarity, and contrast than a normally exposed image regardless of the background color; (ii) the background color does not affect the quality of HDR fingerprint images overall, but the multi‐color background may increase the contrast of HDR fingerprint images in some cases.