CONTENTS OF ISSUE OF "Rock Art Research" link

Volume 13, Number 2, November 1996 Editorial A nano approach to the study of rock art: 'The Walkunders', Chillagoe, north Queensland, Australia Alan Watchman and Elizabeth Hatte (Australia) Pigment Analyses from Panther Cave, Texas Marian Hyman, Solveig A. Turpin and Michael E. Zolensky (U.S.A.) Material culture in Kimberley rock art, Australia David M. Welch (Australia) Palaeoindian bedrock petroglyphs at Epullán Grande Cave, northern Patagonia, Argentina Eduardo A. Crivelli Montero and Mabel M. Fernández (Argentina) With Comment by R. G. Bednarik RAR Debates Ethical and conservation issues in removing lichens from petroglyphs, by Alice M. Tratebas and Fred Chapman (U.S.A.) Response to Alice M. Tratebas and Fred Chapman, by Beverly Childers (U.S.A.) Brief Reports Cave Paintings in Yunnan, China, by Peng Fei (Japan) More on massive intervention: the Aspeberget structure, by Paul G. Bahn (United Kingdom) and Anne-Sophie Hygen (Norway) Reviews & Abstracts With contribution by R. G. Bednarik Recent books of interest Recent papers of interest Orientation AURA Inter-Congress Symposium Melbourne symposium field trips Archaeometry conference Other forthcoming events Input sought for heritage guidelines Obituary: Professor Herbert F. Nowak Clarification New AURA members IFRAO Report No. 17 Let's save Toro Muerto (Peru) Institutum Canarium New IFRAO member: Eastern States Rock Art Research Association The Meeting in Machias, Maine Rationale for SIARB Symposium 5: Administration and conservation of rock art SIARB International Rock Art Congress At last! The definitive volume on rock art management and preservation The following volume has been released by AURA in September 1996. It is by far the most comprehensive book ever published on rock art management and preservation, featuring the contributions of two of the symposia of the Second AURA Congress, held in Cairns. This volume, which includes several contributions by Aboriginal scholars, is absolutely essential reading for anyone involved in the physical preservation or conservation of rock art, or in the ethics and techniques of site management, and in the presentation of public rock art sites. Please order your copy now from AURA, P.O. Box 216, Caulfield South, Vic. 3162, Australia. Number 9, 1996: Management of rock imagery, edited by G. K. Ward and L. A. Ward, bound with Preservation of rock art, edited by A. Thorn and J. Brunet. Proceedings of Symposia G and H of the Second AURA Congress, with contributions by 56 authors. 240 pages, 110 plates, 47 line drawings, 16 maps, 20 tables, extensive bibliographies, paperback, RRP $A48.00, 50% discount for members of IFRAO-affiliated rock art associations. ISBN 0 9586802 0 5. Special offer to members of IFRAO-affiliated organisations: including postage and packing, US$30.60 to any country. Digital colour re-constitution of rock art records By Robert G. Bednarik, Convener, IFRAO A major problem in rock art research is that both the rock art and the photographic record of it have a limited life span. Indeed, the life expectancy of the latter is considerably shorter than that of the former. No possible conservation measures can realistically be expected to secure the perpetual survival of either rock art or its photographs. Calibrated electronic preservation of rock art imagery is an alternative that has not been achieved until recently. The idea, essentially, is to store colour-corrected rock art records digitally, in which form they will eventually survive indefinitely. The International Federation of Rock Art Organizations (IFRAO) in collaboration with the National Museum of Man in India has recently conducted the first digital colour re-constitution of rock art imagery (or, indeed, any other imagery). It is now possible, with commercially available equipment, to recreate the true colour of rock art and rock patination at the moment a photograph was taken of it (Bednarik and Seshadri 1995). This compensates for the distortions inherent in all photography, as well as the fading of photographic dyes due to prolonged storage. Consequently an image can be rejuvenated at any time, and repeatedly, until future technology will permit the fully permanent storage of vast numbers of images. In other words, the fading rock art as well as the fading photographic record of it can now be preserved electronically. The applications of this new technique are very diverse (colour fidelity, printing, conservation, monitoring, dating, cross-referencing, colour enhancement, archival storage etc.), and other disciplines are already using our calibration standard now. Among the people who have decided to do so are museologists, palaeontologists, archaeologists, soil scientists and conservators. This calibration reference device system is designed around the IFRAO Standard Scale. The IFRAO Standard Scale is being distributed throughout the world by IFRAO (Bednarik 1994). For best results in photographs, videos or films of rock art (or indeed any object for purposes requiring very high colour fidelity) the following recommendations are useful: 1. Recording medium: The colour calibration input should preferably be as slides (transparencies) or colour negatives. 2. Lighting: Natural lighting is clearly superior to artificial light, which means that increased exposure times are preferable to the use of flash or other artificial lighting. Where necessary and possible, use a sunlight reflector. Avoid direct lighting in dark locations, and when using artificial lighting, use white light, not yellow halogen light. 3. Direction: Where artificial light is necessary, and especially for three-dimensional subjects (petro-glyphs, cupules), the light source should be from the upper left, and the Scale should also be on the left upper corner of the frame. 4. Area: Full 100 per cent calibration, which would result in a colour re-constitution adequate for rigorous technical and scientific purposes, requires that at least 5-10 per cent of the photograph's area should be occupied by the Scale. With standard lenses this might correspond to a distance of about 60 cm to 1 m. There is a gradual but initially negligible loss in reliability as the image area occupied by the Scale decreases with distance. 5. Distance: One Scale suffices for distances of up to 1.5 m. If uneven lighting is unavoidable, place the Scale in the better lit section. For distances between 1.5 and 3 m, two scales must be used for optimal results: place one of them anywhere suitable, but the second one always vertically and in the upper left corner of the frame. Beyond a distance of 3 m, the Scale is too small to permit a calibration level approaching 100 percent, because at that distance the colour chips become too small to obtain precise digital readings from (i.e. using lenses of standard focal length). 6. Alignment: Care must be taken to position the Scale so that it is parallel to the predominant plane of the rock art motif, and about the same distance from the camera lens. 7. Reflection: The Scale has been printed on matt stock, but this does not eliminate reflection entirely. If a camera-mounted flash is used, the scale must not be at right angle to the camera's focal axis, and if the subject is side-lit, the Scale should be perpendicular to the focal axis. IFRAO, P.O. Box 216, Caulfield South, Vic. 3162 Acknowledgments: The IFRAO Standard Scale and Colour Calibration Projects have been supported by the Australian Institute of Aboriginal and Torres Strait Islander Studies, by the Australia-India Council, and by the Indira Gandhi Rashtriya Manav Sangrahalaya. References Bednarik, R. G. 1991. The IFRAO Standard Scale. Rock Art Research 8: 78-79. Bednarik, R. G. and K. Seshadri 1995. Digital colour re-constitution in rock art photography. Rock Art Research 12: 42-51.78 Rock Art Research 1996 - Volume 13, Number 2.

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