470 likes | 642 Views
Creating visual resources. Visual artefacts, photographs and large format originals. Content of this session. Visual artefacts Types and characteristics of photographs Methods of capture Methods of providing access Special handling. Visual artefacts. Huge category of visual materials
E N D
Creating visual resources Visual artefacts, photographs and large format originals
Content of this session • Visual artefacts • Types and characteristics of photographs • Methods of capture • Methods of providing access • Special handling
Visual artefacts • Huge category of visual materials • paintings and drawings • fabrics • art objects • technical drawings • maps • 3-D objects
1930 map locating Painswick village inside folded printed change of address flier for Pyllis Barron and Dorothy Larcher
Types of photographs • Wide range • Prints • Negatives (acetate, nitrate, glass plates, paper) • Transparencies • Slides • Daguerreotypes and other special formats • Digital originals
John Ruskin's Daguerreotype of a group of windows in the façade of the Casa degli Zane, Venice
Characteristics of photographs • Multiple versions possible • Negative and the print and copy photography • Colour and monotones – fidelity is vital • May be fragile, dirty and even combustible • May be flexible or rigid, mounted or in strips (e.g. albums, slides, negative strips) • Will probably need special handling • Will benefit from specialist equipment
Capture methods for visual artefacts and photographs • Digital Imaging • digital cameras (as for manuscripts) • Scanning • flatbed scanners – primarily for prints and plates • drum scanners – primarily for transparencies • film scanners – specialist high end products • slide scanners – slides and transparencies
Handling • Every single interaction with a fragile original can compromise it • Many of these may be hundreds of years old … • … we want them to last for hundreds more years • So special handling is crucial
Handling • Conservation practice in human handling • Heat levels – most critical due to build up • Light levels • Dust-free environment
Image Quality • How do we know if it is good enough? • Visual sharpness • Laterally reversed images • Dirt • Skew • Image completeness • Guidance available from the RLG • Publications by Franziska Frey (Rochester Institute of Technology)
Case Study: CVMA • Corpus Vitrearum Medii Aevi – medieval stained glass • The content is only renderable from photographs of the subject. • Comprehensive database with high levels of descriptive metadata. • Further additions will include maps and church plans linked to window images.
Specifications of CVMA Digitisation Source:35mm slides, medium & large format transparencies, photographic prints Scanning dpi: 35mm – 2,700 dpi Medium format – 1,200 dpi Large format – 1,000 dpi Print – 600 dpi All 24-bit RGB colour File formats: TIFF master (uncompressed) JPEG for web Courtesy of CVMA Project, Courtauld Institute of Art
Case Study: Shetland Isles Museum • Glass plate collection - >80,000 items • In-house scanning using flatbed scanners • 600 dpi, 8-bit greyscale specification • Delivered on the web with the option to buy content. • Online images are thus relatively small.
Large format originals • Maps • Drawings • Technical drawings – engineering or architectural • Very hard to scan – photographic surrogate is often the best method • Accurately representing scale is difficult • Representing this content online is difficult
Digitization options for 3-D objects • What do we mean by 3-D objects? • Anything! • Sculpture • Public monuments • Machinery • Archaeological artefacts • Buildings • Books
Digitization options for 3-D objects • What are the options? • 2-D photography in single shots • 2-D photography in multiple shots • resultant images stitched into a 3-D rendition using Quicktime • Video • Use of programs such as Macromedia Shockwave to create 3-D Virtual Reality
Lewis and Clark magnetic compass 108 photographs stitched together Quicktime VR
The Tibetan and Himalayan Digital Library, University of Virginia The Tibetan and Himalayan Digital Library, University of Virginia
The Tibetan and Himalayan Digital Library, University of Virginia Panorama
Eternal Egypt Shockwave Eternal Egypt Project Shockwave