5DT813, Panel 1, composite of 4
tracings, Photo and drawing from
Carol Patterson.
I would
suppose that most of us have been involved to some extent with recording rock
art. 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. However, in the rock art recording projects I have done some
of the volunteer recorders turn in really poor drawings that look like they
were done by a child. Not everyone has had training in close observation and
drawing.
I have
recently had the pleasure of reading the 2006 report on the rock art of Eagle
Rock Shelter (5DT813) done by Dr. Carol Patterson and Dr. Alan Watchman, and I
was struck by the high quality of the documentation produced. I am especially
impressed by the quality of the drawings of the rock art panels that they
included with all the photographs in this report. I want to pass on to you the
process they used and show some examples of the remarkable quality they
achieved.
5DT813, Panel 8, left side.
"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. Colorado State Historical Society forms were completed for each
panel. Digital and film photography was used for recording each 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. 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." (Patterson and Watchman 2006:23)
This, in
itself, exceeds the standard for many rock art recording projects, but this is
just the beginning for Carol and Alan in their determination for accuracy in
the final record.
5DT813, Panel 16, Photo and
drawing from Carol Patterson.
"The techniques used for documenting the rock art were as follows:
1. 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. Each photograph included a distance
and color scale.
2. These images were downloaded to a
computer and processed through Adobe PhotoShop 7.0 and adjusted to reduce the
glare and increase the contrast. This improved the visibility of the
petroglyphs that had been obscured by dust and reflections.
3. Each panel was printed out and
put into a plastic sleeve with a second and third layer of plastic over it.
Drawings were then made on the plastic in the field as described below." (Patterson and Watchman 2006:23)
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. 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. The third and last sheet
over the petroglyph was labeled 'petroglyph' and with a 'pecking' motion, a dot
was placed in every single pecked mark that could be seen on the photograph and
check(ed) on the panel surface. The resulting ink drawings on plastic were then
scanned to produce a single graphic representation of the panel. 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
2006:23)
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. 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. Elements of a rock art panel
from different cultures and ages could be easily recorded separately but then
also presented in combination. Another variation that Carol has tested is to
use colored pens on the different layers to bring out differences more clearly.
While
working to this standard would obviously take more time than by usual methods,
the results are clearly worth it. The beautifully detailed resulting drawings,
with their separate layers of information, allow study at a deeper level and
finer factual analysis than those of most reports. Well done!
REFERENCE:
Patterson,
Carol, Dr., and Dr. Alan Watchman
2006 Gunnison River Rock Art Site (5DT813), Delta
County: Documentation, Evaluation, and Management Plan. Submitted for Julie Coleman, BLM Archaeologist, BLM Field Office,
Montrose, CO, 80401, Urraca Archaeological Services, Montrose, Colorado
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