Computational Schlieren Photography with Light Field Probes
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Schlieren Imaging
Traldi et al. EPJ Techniques and Instrumentation (2018) 5:4 https://doi.org/10.1140/epjti/s40485-018-0045-1 RESEARCH ARTICLE Open Access Schlieren imaging: a powerful tool for atmospheric plasma diagnostic Enrico Traldi1, Marco Boselli1,2, Emanuele Simoncelli1, Augusto Stancampiano3, Matteo Gherardi1,2, Vittorio Colombo1,2* and Gary S. Settles4* * Correspondence: vittorio. [email protected]; [email protected] Abstract 1Department of Industrial Engineering, Alma Mater Studiorum Schlieren imaging has been widely used in science and technology to investigate – Università di Bologna, Viale del phenomena occurring in transparent media. In particular, it has proven to be a Risorgimento 2, 40136 Bologna, Italy powerful tool in fundamental studies and process optimization for atmospheric 4FloViz Inc., Port Matilda, PA 16870, USA pressure plasma diagnostics, providing qualitative and (in some cases) also Full list of author information is quantitative information on the fluid-dynamic characteristics of plasmas generated available at the end of the article by many different types of sources. However, obtaining significant and reliable results by schlieren imaging can be challenging, especially when considering the variety of geometries and applications of atmospheric pressure plasma sources. Therefore, it is necessary to adopt solutions that can address the specific issues of different plasma-assisted processes. In this paper, an overview on the use of the schlieren imaging technique for atmospheric pressure plasma characterization is presented. In the first part, the physical principles behind this technique and the different setups that can be adopted to perform it are presented. In the second part, examples of schlieren imaging applied to different kinds of atmospheric pressure plasmas (non-equilibrium plasma jets, plasma actuators for flow control and thermal plasma sources) are presented, showing how it was used to characterize the fluid-dynamic behavior of plasma-assisted processes and reporting best practices in performing this diagnostic technique. -
US Army Photography Course Laboratory Procedures SS0509
SUBCOURSE EDITION SS0509 8 LABORATORY PROCEDURES US ARMY STILL PHOTOGRAPHIC SPECIALIST MOS 84B SKILL LEVEL 1 AUTHORSHIP RESPONSIBILITY: SSG Dennis L. Foster 560th Signal Battalion Visual Information/Calibration Training Development Division Lowry AFB, Colorado LABORATORY PROCEDURES SUBCOURSE NO. SS0509-8 (Developmental Date: 30 June 1988) US Army Signal Center and Fort Gordon Fort Gordon, Georgia Five Credit Hours GENERAL The laboratory procedures subcourse is designed to teach tasks related to work in a photographic laboratory. Information is provided on the types and uses of chemistry, procedures for processing negatives and prints, and for mixing and storing chemicals, procedures for producing contact and projection prints, and photographic quality control. This subcourse is divided into three lessons with each lesson corresponding to a terminal learning objective as indicated below. Lesson 1: PREPARATION OF PHOTOGRAPHIC CHEMISTRY TASK: Determine the types and uses of chemistry, for both black and white and color, the procedures for processing negatives and prints, the procedures for mixing and storing chemicals. CONDITIONS: Given information and diagrams on the types of chemistry and procedures for mixing and storage. STANDARDS: Demonstrate competency of the task skills and knowledge by correctly responding to at least 75% of the multiple-choice test covering preparation of photographic chemistry. (This objective supports SM tasks 113-578-3022, Mix Photographic Chemistry; 113-578-3023, Process Black and White Film Manually; 113-578-3024, Dry Negatives in Photographic Film Drier; 113-578-3026, Process Black and White Photographic Paper). i Lesson 2: PRODUCE A PHOTOGRAPHIC PRINT TASK: Perform the procedures for producing an acceptable contact and projection print. -
Introduction to Shadowgraph and Schlieren Imaging Andrew Davidhazy
Rochester Institute of Technology RIT Scholar Works Articles 2006 Introduction to shadowgraph and schlieren imaging Andrew Davidhazy Follow this and additional works at: http://scholarworks.rit.edu/article Recommended Citation Davidhazy, Andrew, "Introduction to shadowgraph and schlieren imaging" (2006). Accessed from http://scholarworks.rit.edu/article/478 This Technical Report is brought to you for free and open access by RIT Scholar Works. It has been accepted for inclusion in Articles by an authorized administrator of RIT Scholar Works. For more information, please contact [email protected]. INTRODUCTION TO SHADOHGRAPH AND SCHLIEREN IMAGING Andrew Davidhazy Rochester In.titute of Technology Imaging and Photoqraphic Technology Schlieren photography is not new. It's a technique peripherally developed by early astronomers and glass maker•. It is a word that has it's origin in the german word "schliereN or streaks, caused by inhomogeneous areas in glass. A variety of methods were used to detect these .chliere, with some of them probably closely related to the technique. which we are about to examine. There are three basic types of - SI-tAbOIJ612APHS optical probing systems each with intrinsic merits and limitations. -SCHLIE'REN These are shadowqraphs, schlieren images, and interferograms. The5e are -UffiRffRD6I2AHS lis~ed in order of increasing complexi~y and pos5ible varia~ions. In ~he mid 1800's, Leon Foucault developed a test ~ha~ bears his name for examining the figure or curvature of as~ronomical mirrors. Worker5 testing mirror.~i~n the Foucault ~est were well aware of, and took great pains to minimize, the disturbing effects of density gradients present between the light FOUCAULT source, the mirror and the "knife edge". -
Fresnel Zone Plate Imaging in Nuclear Medicine
FRESNEL ZONE PLATE IMAGING IN NUCLEAR MEDICINE Harrison H. Barrett Raytheon Research Division, Waltham, Massachusetts Considerable progress has been made in recent so that there is essentially no collimation. The zone years in detecting the scintillation pattern produced plate has a series of equi-area annular zones, alter by a gamma-ray image. Systems such as the Anger nately transparent and opaque to the gamma rays, camera (7) and Autoflouroscope (2) give efficient with the edges of the zones located at radii given by counting while an image intensifier camera (3,4) rn = n = 1,2, N. gives better spatial resolution at some sacrifice in (D efficiency. However, the common means of image To understand the operation of this aperture, con formation, the pinhole aperture and parallel-hole sider first a point source of gamma rays. Then collimator, are very inefficient. Only a tiny fraction the scintillation pattern on the crystal is a projected (~0.1-0.01%) of the gamma-ray photons emitted shadow of the zone plate, with the position of the by the source are transmitted to the detector plane shadow depending linearly on the position of the (scintillator crystal), and this fraction can be in source. The shadow thus contains the desired infor creased only by unacceptably degrading the spatial mation about the source location. It may be regarded resolution. It would be desirable, of course, to have as a coded image similar to a hologram. Indeed, a a large-aperture, gamma-ray lens so that good col Fresnel zone plate is simply the hologram of a point lection efficiency and good resolution could be ob source (9). -
Aeronautical Laboratories Institute
GRADUATEAERONAUTICAL LABORATORIES CALIFORNIAINSTITUTE of TECHNOLOGY Pasadena, California 91125 The Supersonic Hydrogen-Fluorine Combustion Facility Design Review Report Version 4.0 by Jeffery Hall and Pad Dimotakis GALCIT Internal Report 30 August 1989 Acknowledgements This development of the facility to be described below is the outgrowth of a design, theoretical and experimental effort at GALCIT that began over ten years ago to study high Reynolds number turbulent mixing under Air Force Office of Scientific Research sponsor- ship. A large number of people have contributed to the development of this facility, which has been realized as a result of their contributions and the long-term support by AFOSR, with Dr. Julian Tishkoff the current program manager, which we gratefully acknowledge*. The first phase of that effort, which involved the study and behavior of subsonic shear layers, was realized in the subsonic shear layer facility which was designed and fabricated with the aid and contributions of several people. That design was modeled after the smaller subsonic facility built by Wallace (1981) under the supervision of Garry Brown, Professor in Aeronautics at the time and presently director of ARL in Australia. The GALCIT subsonic facility design was begun by r Brian Cantwell, Research Fellow in Aeronautics at the time, presently Professor at Stanford, in collaboration with and under the guidance of Garry Brown. It was completed and used as part of the P11.D. thesis research of M. Godfrey Mungal, Graduate Research Assistant and subsequently Research Fellow in Aeronautics, presently Assistant Professor at Stanford, under the guidance of H. W. L'iepmann, Director of GALCIT at the time and presently Professor Emer- itus in Aeronautics, and P. -
Quantitative Schlieren Measurement of Explosively‐Driven Shock Wave
Full Paper DOI: 10.1002/prep.201600097 Quantitative Schlieren Measurement of Explosively-Driven Shock Wave Density, Temperature, and Pressure Profiles Jesse D. Tobin[a] and Michael J. Hargather*[a] Abstract: Shock waves produced from the detonation of the shock wave temperature decay profile. Alternatively, laboratory-scale explosive charges are characterized using the shock wave pressure decay profile can be estimated by high-speed, quantitative schlieren imaging. This imaging assuming the shape of the temperature decay. Results are allows the refractive index gradient field to be measured presented for two explosive sources. The results demon- and converted to a density field using an Abel deconvolu- strate the ability to measure both temperature and pres- tion. The density field is used in conjunction with simulta- sure decay profiles optically for spherical shock waves that neous piezoelectric pressure measurements to determine have detached from the driving explosion product gases. Keywords: Schlieren · Explosive temperature · Quantitative optical techniques 1 Introduction Characterization of explosive effects has traditionally been charge. This work used the quantitative density measure- performed using pressure gages and various measures of ment to estimate the pressure field and impulse produced damage, such as plate dents, to determine a “TNT Equiva- by the explosion as a function of distance. The pressure lence” of a blast [1,2]. Most of the traditional methods, measurement, however, relied on an assumed temperature. however, result in numerous equivalencies for the same The measurement of temperature in explosive events material due to large uncertainties and dependencies of can be considered a “holy grail”, which many researchers the equivalence on the distance from the explosion [3,4]. -
Utvrđivanje Izvornika Analognih I Digitalnih Fotografija
Filozofski fakultet Hrvoje Gržina UTVRĐIVANJE IZVORNIKA ANALOGNIH I DIGITALNIH FOTOGRAFIJA DOKTORSKI RAD Zagreb, 2017. Faculty of Humanities and Social Sciences Hrvoje Gržina IDENTIFYING ORIGINALS OF ANALOG AND DIGITAL PHOTOGRAPHS DOCTORAL THESIS Zagreb, 2017 Filozofski fakultet Hrvoje Gržina UTVRĐIVANJE IZVORNIKA ANALOGNIH I DIGITALNIH FOTOGRAFIJA DOKTORSKI RAD Mentor: dr. sc. Hrvoje Stančić, izv. prof. Zagreb, 2017. Faculty of Humanities and Social Sciences Hrvoje Gržina IDENTIFYING ORIGINALS OF ANALOG AND DIGITAL PHOTOGRAPHS DOCTORAL THESIS Supervisor: Ph. D. Hrvoje Stančić, Associate Professor Zagreb, 2017 O MENTORU Dr. sc. Hrvoje Stančić, izv. prof. rođen je 2. listopada 1970. u Zagrebu gdje je završio osnovnu i srednju školu. Diplomirao je 1996. godine studijske grupe Informatologija (smjer Opća informatologija) i Engleski jezik i književnost na Filozofskome fakultetu u Zagrebu. Godine 1996. prihvaćen je kao znanstveni novak na projektu koji se vodi na Odsjeku za informacijske znanosti Filozofskoga fakulteta u Zagrebu (broj znanstvenika 244003). Magistrirao je 2001. godine s temom Upravljanje znanjem i globalna informacijska infrastruktura. Doktorirao je 2006. s temom Teorijski model postojanog očuvanja autentičnosti elektroničkih informacijskih objekata. Od listopada 2011. u zvanju je izvanrednoga profesora, a od 2014. godine u zvanju znanstvenoga savjetnika. Predstojnik je Katedre za arhivistiku i dokumentalistiku od 2008. godine. Nastavu izvodi na preddiplomskom, diplomskom i doktorskom studiju informacijskih i komunikacijskih -
The Integrity of the Image
world press photo Report THE INTEGRITY OF THE IMAGE Current practices and accepted standards relating to the manipulation of still images in photojournalism and documentary photography A World Press Photo Research Project By Dr David Campbell November 2014 Published by the World Press Photo Academy Contents Executive Summary 2 8 Detecting Manipulation 14 1 Introduction 3 9 Verification 16 2 Methodology 4 10 Conclusion 18 3 Meaning of Manipulation 5 Appendix I: Research Questions 19 4 History of Manipulation 6 Appendix II: Resources: Formal Statements on Photographic Manipulation 19 5 Impact of Digital Revolution 7 About the Author 20 6 Accepted Standards and Current Practices 10 About World Press Photo 20 7 Grey Area of Processing 12 world press photo 1 | The Integrity of the Image – David Campbell/World Press Photo Executive Summary 1 The World Press Photo research project on “The Integrity of the 6 What constitutes a “minor” versus an “excessive” change is necessarily Image” was commissioned in June 2014 in order to assess what current interpretative. Respondents say that judgment is on a case-by-case basis, practice and accepted standards relating to the manipulation of still and suggest that there will never be a clear line demarcating these concepts. images in photojournalism and documentary photography are world- wide. 7 We are now in an era of computational photography, where most cameras capture data rather than images. This means that there is no 2 The research is based on a survey of 45 industry professionals from original image, and that all images require processing to exist. 15 countries, conducted using both semi-structured personal interviews and email correspondence, and supplemented with secondary research of online and library resources. -
Name, a Novel
NAME, A NOVEL toadex hobogrammathon /ubu editions 2004 Name, A Novel Toadex Hobogrammathon Cover Ilustration: “Psycles”, Excerpts from The Bikeriders, Danny Lyon' book about the Chicago Outlaws motorcycle club. Printed in Aspen 4: The McLuhan Issue. Thefull text can be accessed in UbuWeb’s Aspen archive: ubu.com/aspen. /ubueditions ubu.com Series Editor: Brian Kim Stefans ©2004 /ubueditions NAME, A NOVEL toadex hobogrammathon /ubueditions 2004 name, a novel toadex hobogrammathon ade Foreskin stepped off the plank. The smell of turbid waters struck him, as though fro afar, and he thought of Spain, medallions, and cork. How long had it been, sussing reader, since J he had been in Spain with all those corkoid Spanish medallions, granted him by Generalissimo Hieronimo Susstro? Thirty, thirty-three years? Or maybe eighty-seven? Anyhow, as he slipped a whip clap down, he thought he might greet REVERSE BLOOD NUT 1, if only he could clear a wasp. And the plank was homely. After greeting a flock of fried antlers at the shevroad tuesday plied canticle massacre with a flash of blessed venom, he had been inter- viewed, but briefly, by the skinny wench of a woman. But now he was in Rio, fresh of a plank and trying to catch some asscheeks before heading on to Remorse. I first came in the twilight of the Soviet. Swigging some muck, and lampreys, like a bad dram in a Soviet plezhvadya dish, licking an anagram off my hands so the ——— woundn’t foust a stiff trinket up me. So that the Soviets would find out. -
On the Export Control of High Speed Imaging for Nuclear Weapons Applications
LA-UR-17-28408 Approved for public release; distribution is unlimited. Title: On The Export Control Of High Speed Imaging For Nuclear Weapons Applications Author(s): Watson, Scott Avery Altherr, Michael Robert Intended for: Report Issued: 2017-09-15 Disclaimer: Los Alamos National Laboratory, an affirmative action/equal opportunity employer, is operated by the Los Alamos National Security, LLC for the National Nuclear Security Administration of the U.S. Department of Energy under contract DE-AC52-06NA25396. By approving this article, the publisher recognizes that the U.S. Government retains nonexclusive, royalty-free license to publish or reproduce the published form of this contribution, or to allow others to do so, for U.S. Government purposes. Los Alamos National Laboratory requests that the publisher identify this article as work performed under the auspices of the U.S. Department of Energy. Los Alamos National Laboratory strongly supports academic freedom and a researcher's right to publish; as an institution, however, the Laboratory does not endorse the viewpoint of a publication or guarantee its technical correctness. On The Export Control of High-Speed Imaging for Nuclear Weapons Applications By Scott Watson, and Michael Altherr Los Alamos National Lab LA-UR-XYZQ 2017. Abstract Since the Manhattan Project, the use of high-speed photography, and its cousins flash radiography1 and schieleren photography have been a technological proliferation concern. Indeed, like the supercomputer, the development of high-speed photography as we now know it essentially grew out of the nuclear weapons program at Los Alamos2,3,4. Naturally, during the course of the last 75 years the technology associated with computers and cameras has been export controlled by the United States and others to prevent both proliferation among non-P5-nations and technological parity among potential adversaries among P5 nations. -
Schlieren Imaging and Flow Analysis on a Cone/Flare Model in the AFRL Mach 6 Ludwieg Tube Facility" (2019)
Air Force Institute of Technology AFIT Scholar Theses and Dissertations Student Graduate Works 3-21-2019 Schlieren Imaging and Flow Analysis on a Cone/ Flare Model in the AFRL Mach 6 Ludwieg Tube Facility David A. Labuda Follow this and additional works at: https://scholar.afit.edu/etd Part of the Aerospace Engineering Commons, Fluid Dynamics Commons, and the Mathematics Commons Recommended Citation Labuda, David A., "Schlieren Imaging and Flow Analysis on a Cone/Flare Model in the AFRL Mach 6 Ludwieg Tube Facility" (2019). Theses and Dissertations. 2224. https://scholar.afit.edu/etd/2224 This Thesis is brought to you for free and open access by the Student Graduate Works at AFIT Scholar. It has been accepted for inclusion in Theses and Dissertations by an authorized administrator of AFIT Scholar. For more information, please contact [email protected]. SCHLIEREN IMAGING AND FLOW ANALYSIS ON A CONE/FLARE MODEL IN THE AFRL MACH 6 LUDWIEG TUBE FACILITY THESIS David A. LaBuda, Second Lieutenant, USAF AFIT-ENY-MS-19-M-226 DEPARTMENT OF THE AIR FORCE AIR UNIVERSITY AIR FORCE INSTITUTE OF TECHNOLOGY Wright-Patterson Air Force Base, Ohio DISTRIBUTION STATEMENT A. APPROVED FOR PUBLIC RELEASE; DISTRIBUTION UNLIMITED. The views expressed in this thesis are those of the author and do not reflect the official policy or position of the United States Air Force, Department of Defense, or the United States Government. This material is declared a work of the U.S. Government and is not subject to copyright protection in the United States. AFIT-ENY-MS-19-M-226 SCHLIEREN IMAGING AND FLOW ANALYSIS ON A CONE/FLARE MODEL IN THE AFRL MACH 6 LUDWIEG TUBE FACILITY THESIS Presented to the Faculty Department of Aeronautics and Astronautics Graduate School of Engineering and Management Air Force Institute of Technology Air University Air Education and Training Command In Partial Fulfillment of the Requirements for the Degree of Master of Science in Aeronautical Engineering David A. -
Hand-Held Schlieren Photography with Light Field Probes
Hand-held Schlieren Photography with Light Field probes The MIT Faculty has made this article openly available. Please share how this access benefits you. Your story matters. Citation Wetzstein, Gordon, Ramesh Raskar, and Wolfgang Heidrich. “Hand- held Schlieren Photography with Light Field probes.” In 2011 IEEE International Conference on Computational Photography (ICCP), 1-8. As Published http://dx.doi.org/10.1109/ICCPHOT.2011.5753123 Publisher Institute of Electrical and Electronics Engineers (IEEE) Version Author's final manuscript Citable link http://hdl.handle.net/1721.1/79911 Terms of Use Creative Commons Attribution-Noncommercial-Share Alike 3.0 Detailed Terms http://creativecommons.org/licenses/by-nc-sa/3.0/ Hand-Held Schlieren Photography with Light Field Probes Gordon Wetzstein1;2 Ramesh Raskar2 Wolfgang Heidrich1 1The University of British Columbia 2MIT Media Lab Abstract We introduce a new approach to capturing refraction in transparent media, which we call Light Field Back- ground Oriented Schlieren Photography (LFBOS). By op- tically coding the locations and directions of light rays emerging from a light field probe, we can capture changes of the refractive index field between the probe and a camera or an observer. Rather than using complicated and expen- sive optical setups as in traditional Schlieren photography we employ commodity hardware; our prototype consists of a camera and a lenslet array. By carefully encoding the color and intensity variations of a 4D probe instead of a diffuse 2D background, we avoid expensive computational process- ing of the captured data, which is necessary for Background Oriented Schlieren imaging (BOS). We analyze the bene- fits and limitations of our approach and discuss application scenarios.