Digital photographs manipulated in Adobe Photoshop for color enhancement revealed the remnant red paint on several panels.The whole site is basically weathered sandstone with engravings covered with dust and encrustations combined with some areas that are chalked, rubbed from cattle, spalling, and washed by rain and affected by seepage and algal growth."1.This improved the visibility of the petroglyphs that had been obscured by dust and reflections.Then the actual drawing on the plastic sleeves is described as follows: "Each panel printout in its plastic sleeve was put on a clip board and taken back to the field.If so, you have to be aware that the least controllable aspect of any such project is the drawing of the rock art panel.Drawing is still vitally important because we can always see things on the rock surface that the camera does not pick up.
The plastic sheets were assembled to produce a full reproduction of each panel, including cracks and notes about threats to the panel, or scanned separately to obtain specific information about each panel." (Patterson and Watchman 20)Notice that the drawing is done by tracing the photograph of the panel while in front of the panel to that each detail can be double checked against what is actually there, but various aspects of the panel are drawn on different sheets of plastic so they can be examined separately if so desired.I want to pass on to you the process they used and show some examples of the remarkable quality they achieved."The documentation of the Gunnison Gorge rock art site was conducted in a systematic manner that employed site mapping, drawing of the plan and elevation, ink drawings and GPS recordings.light from some minerals and certain other crystalline materials.The light energy released is derived from electron displacements within the crystal lattice of such a substance caused by previous exposure to high-energy radiation.Systematic digital photographing of each panel, at the same distance and at right angles to the panel to produce a color reproduction of the entire panel.Some panels required two or more photographs to capture the entire panel.The petroglyphs are very difficult to see, and film photography would not reveal enough detail for quality reproductions.Black and white photographs were taken for archival records, but the very faint paint remnants are not visible in this format.Doing final scans of each sheet separately, and then combined, seems to me to be a wonderful way of recording all aspects of the rock art panel and combining the accuracy of tracing off of a photograph with the ability to detect details and subtle variations by human observation of the actual rock art.Variations of this technique could be used for rock art panels in different situations: for instance figures with both painting and pecking could be recorded with the paint and pecking on different plastic sheets so the differing techniques could be studied separately and then combined as well.In front of the petroglyph panel, the color photograph was traced on the plastic sleeve.The first sheet of plastic was labeled 'geology' and on it was drawn the rock features, cracks, spalling and scratches.The second sheet was labeled 'chalk' and the chalked areas were reproduced on this sheet.