Applied photo interpretation for airbrush cartographyLunar and planetary exploration has required the development of new techniques of cartographic portrayal. Conventional photo-interpretive methods employing size, shape, shadow, tone, pattern, and texture are applied to computer-processed satellite television images. Comparative judgements are affected by illumination, resolution, variations in surface coloration, and transmission or processing artifacts. The portrayal of tonal densities in a relief illustration is performed using a unique airbrush technique derived from hill-shading of contour maps. The control of tone and line quality is essential because the mid-gray to dark tone densities must be finalized prior to the addition of highlights to the drawing. This is done with an electric eraser until the drawing is completed. The drawing density is controlled with a reflectance-reading densitometer to meet certain density guidelines. The versatility of planetary photo-interpretive methods for airbrushed map portrayals is demonstrated by the application of these techniques to the synthesis of nonrelief data.
Document ID
19760055547
Acquisition Source
Legacy CDMS
Document Type
Conference Proceedings
Authors
Inge, J. L. (Geological Survey Flagstaff, AZ, United States)
Bridges, P. M. (U.S. Geological Survey, Center of Astrogeology, Flagstaff Ariz., United States)