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G. Rock art will be professionally recorded to achieve archival quality. <br />Efforts should be made to meet minimum standards as outlined by Conner et <br />• al. 1980: 39-41. In addition to Rock Art recordation, it may be <br />possible to remove some panels. Where this is structurally practical it <br />will be done: <br />1. Standards outlined by Conner et all., 1980: 39-41. <br />a. Use of a large (4" X 5" or larger) format camera system with <br />adequate perspective control capabilities (swings and <br />tilts). <br />Use of professional quality lenses with low distortion and <br />high resolution characteristics. Prime lenses should be of <br />sufficient focal length to avoid any wide angle distortion <br />effects. <br />c. Use of panchromatic black and white film as the primary <br />recording material. The characteristics of this film should <br />include: fine grain, high resolution, dimensional stability, <br />and an appropriate characteristic curve (contrast and tonal <br />range). Color film should be used as a supplemental material <br />or for interpretive purposes, because no currently available <br />color film has proven to be archivally permanent. When using <br />color photography, the cibachrome printing process should be <br />used for color prints (made from Kodachrome transparencies). <br />d. Use of references for scale on horizontal and vertical axis, <br />• thereby allowing precise correction for perspective <br />distortion and recordation of panel and design element sizes. <br />e. Use of a gray scale as a standard reference so that a known <br />tone and contrast value is present in all photographs. (This <br />allows efficient evaluation of film processing and print <br />production, and is useful during subsequent interpretation of <br />the photographs.) <br />f. Use of lighting controls necessary to produce optimum subject <br />contrast. Such controls include timing of exposures to <br />coincide with appropriate natural lighting conditions, and <br />use of supplemental artificial lighting. <br />g. Use of exposure calculations to determine the optimum <br />recording of the subject tonal range. Shadow detail must be <br />adequate to record pertinent information, but key highlights <br />should also be preserved. Exposure and film development <br />should be used to selectively manipulate the contrast of the <br />negative, thereby insuring the clearest possible delineation <br />of rock art design. If necessary, exposures should be <br />bracketed. <br /> <br />