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University of Wollongong Research Online Faculty of Science, Medicine and Health - Papers Faculty of Science, Medicine and Health 2015 Technical considerations and methodology for creating high-resolution, color-corrected, and georectified photomosaics of stratigraphic sections at archaeological sites Erich C. Fisher Arizona State University Derya Akkaynak Massachusetts nI stitute of Technology Jacob Harris Arizona State University Andy I.R Herries La Trobe University Zenobia Jacobs University of Wollongong, [email protected] See next page for additional authors Publication Details Fisher, E. C., Akkaynak, D., Harris, J., Herries, A. I.R., Jacobs, Z., Karkanas, P., Marean, C. W. & Mcgrath, J. R. (2015). Technical considerations and methodology for creating high-resolution, color-corrected, and georectified photomosaics of stratigraphic sections at archaeological sites. Journal of Archaeological Science, 57 380-394. Research Online is the open access institutional repository for the University of Wollongong. For further information contact the UOW Library: [email protected] Technical considerations and methodology for creating high-resolution, color-corrected, and georectified photomosaics of stratigraphic sections at archaeological sites Abstract Using a conventional, off-the-shelf digital single lens reflex camera and flashes, we were able to create high- resolution panoramas of stratigraphic profiles ranging from a single meter to over 5 m in both height and width at the Middle Stone Age site of PP5-6 at Pinnacle Point, Mossel Bay, South Africa. The final photomosaics are isoluminant, rectilinear, and have a pixel spatial resolution of 1 mm. Furthermore, we systematically color-corrected the raw imagery. This process standardized the colors seen across the photomosaics while also creating reproducible and meaningful colors for relative colorimetric analysis between photomosiacs. Here, we provide a detailed discussion about the creation and application of our photomosaics. In the first part of the paper, we examine the specific characteristics of modern digital single lens reflex D( SLR) cameras and lenses that were important to us in developing our methodology. We also provide a detailed discussion about how to reproduce the methodology in the field and to post-process the imagery. In the final section of the paper, we give several examples to show how we apply our photomosaics within an empirical 3D GIS database. These examples are provided to show how photographic data can be integrated with other digitally-captured data and used to study the relationships between the stratigraphic features seen in the photomosaics and the 3D distribution of excavated archaeological piece-plots, geochronological samples, and other kinds of geological samples. Disciplines Medicine and Health Sciences | Social and Behavioral Sciences Publication Details Fisher, E. C., Akkaynak, D., Harris, J., Herries, A. I.R., Jacobs, Z., Karkanas, P., Marean, C. W. & Mcgrath, J. R. (2015). Technical considerations and methodology for creating high-resolution, color-corrected, and georectified photomosaics of stratigraphic sections at archaeological sites. Journal of Archaeological Science, 57 380-394. Authors Erich C. Fisher, Derya Akkaynak, Jacob Harris, Andy I.R Herries, Zenobia Jacobs, Panagiotis Karkanas, Curtis W. Marean, and James R. Mcgrath This journal article is available at Research Online: http://ro.uow.edu.au/smhpapers/3126 Elsevier Editorial System(tm) for Journal of Archaeological Science Manuscript Draft Manuscript Number: JASC14-318R1 Title: Technical Considerations and Methodology for Creating High-resolution, Color-Corrected, and Georectified Photomosaics of Stratigraphic Sections at Archaeological Sites Article Type: Full Length Article Keywords: Archaeoinformatics; Digital Photography; Modern Human Origins; South Africa Corresponding Author: Dr. Erich Fisher, Ph.D. Corresponding Author's Institution: Arizona State University First Author: Erich Fisher, Ph.D. Order of Authors: Erich Fisher, Ph.D.; Derya Akkaynak, Ph.D.; Jacob A Harris, B.A.; Andy Herries, Ph.D.; Zenobia Jacobs, Ph.D.; Panagiotis Karkanas, Ph.D.; Curtis W Marean, Ph.D.; James McGrath, B.A. Abstract: Using a conventional, off-the-shelf digital single lens reflex camera and flashes, we were able to create high-resolution panoramas of stratigraphic profiles ranging from a single meter to over 5 meters in both height and width at the Middle Stone Age site of PP5-6 at Pinnacle Point, Mossel Bay, South Africa. The final photomosaics are isoluminant, rectilinear, and have a pixel spatial resolution of 1 mm. Furthermore, we systematically color-corrected the raw imagery. This process standardized the colors seen across the photomosaics while also creating reproducible and meaningful colors for relative colorimetric analysis between photomosiacs. Here, we provide a detailed discussion about the creation and application of our photomosaics. In the first part of the paper, we examine the specific characteristics of modern digital single lens reflex (DSLR) cameras and lenses that were important to us in developing our methodology. We also provide a detailed discussion about how to reproduce the methodology in the field and to post-process the imagery. In the final section of the paper, we give several examples to show how we apply our photomosaics within an empirical 3D GIS database. These examples are provided to show how photographic data can be integrated with other digitally-captured data and used to study the relationships between the stratigraphic features seen in the photomosaics and the 3D distribution of excavated archaeological piece-plots, geochronological samples, and other kinds of geological samples. *Manuscript Click here to view linked References 1 TITLE: Technical Considerations and Methodology for Creating High-resolution, Color- 2 Corrected, and Georectified Photomosaics of Stratigraphic Sections at Archaeological Sites 3 4 AUTHORS: Erich C. Fisher a*, Derya Akkaynak b,c,d , Jacob Harris a, Andy I. R. Herries e, 5 Zenobia Jacobs g, Panagiotis Karkanas f, Curtis W. Marean a, James McGrath a 6 7 a Institute of Human Origins, School of Human Evolution and Social Change, Arizona State 8 University, Tempe, Arizona 85287-2402 U.S.A; 480-965-1077; [email protected] 9 bDepartment of Mechanical Engineering, Massachusetts Institute of Technology, 77 10 Massachusetts Avenue, Cambridge, MA, 02139, USA 11 cApplied Ocean Science and Engineering, Woods Hole Oceanographic Institution, 266 Woods 12 Hole Road, Woods Hole, MA, 02543 USA 13 dProgram in Sensory Physiology and Behavior, Marine Biological Laboratory, 7 MBL Street, 14 Woods Hole, MA, 02543, USA 15 e Australian Archaeomagnetism Laboratory, Department of Archaeology, Environment and 16 Community Planning, La Trobe University, Melbourne Campus, Bundoora 3086, VIC, 17 Australia. 18 f Ephoreia of Palaeanthropology-Speleology of S. Greece, Ardittou 34b, 11636 Athens, Greece. 19 g Centre for Archaeological Science, School of Earth and Environmental Sciences, University of 20 Wollongong, Northfields Avenue, Wollongong, NewSouth Wales, 2522, Australia. 21 22 *corresponding author 23 Co-authors have been listed alphabetically. Co-authorship is shared equally. 1 24 25 Abstract 26 Using a conventional, off-the-shelf digital single lens reflex camera and flashes, we were able to 27 create high-resolution panoramas of stratigraphic profiles ranging from a single meter to over 5 28 meters in both height and width at the Middle Stone Age site of PP5-6 at Pinnacle Point, Mossel 29 Bay, South Africa. The final photomosaics are isoluminant, rectilinear, and have a pixel spatial 30 resolution of 1 mm. Furthermore, we systematically color-corrected the raw imagery. This 31 process standardized the colors seen across the photomosaics while also creating reproducible 32 and meaningful colors for relative colorimetric analysis between photomosiacs. 33 Here, we provide a detailed discussion about the creation and application of our 34 photomosaics. In the first part of the paper, we examine the specific characteristics of modern 35 digital single lens reflex (DSLR) cameras and lenses that were important to us in developing our 36 methodology. We also provide a detailed discussion about how to reproduce the methodology in 37 the field and to post-process the imagery. In the final section of the paper, we give several 38 examples to show how we apply our photomosaics within an empirical 3D GIS database. These 39 examples are provided to show how photographic data can be integrated with other digitally- 40 captured data and used to study the relationships between the stratigraphic features seen in the 41 photomosaics and the 3D distribution of excavated archaeological piece-plots, geochronological 42 samples, and other kinds of geological samples. 43 44 Keywords 45 Archaeoinformatics; Digital Photography; Modern Human Origins; South Africa 46 2 47 Highlights 48 We create high-resolution, digital photomosaics of archaeological stratigraphic sections. 49 Influences on image quality are reviewed, including equipment technical limitations and 50 setup. 51 We color-calibrate the imagery for relative colorimetric analysis of stratigraphy. 52 We show how photomosaics can be used to explore site formation processes and human 53 behavior. 54 55 1. Introduction 56 57 Archaeological fieldwork has made continual progress in its ability to capture 58 information from the past that is archived in sediments. The different fields of archaeology