Generalized data is better for depicting patterns within mountain ranges and is more tolerant of vertical exaggeration. Topographic detail, vertical exaggeration, and small-scale presentation used in combination are the enemies of legible mountain depiction.Äownsampling GTOPO30 to a sparser resolution alleviates the problems outlined above. Solitary high peaks with small surface area, such as Mount Shasta or the Matterhorn, spike upwards like the Eiffel Tower. Especially problematic are glaciated northern mountains comprised of tightly packed ridges and valleys—for example, the Coast Ranges of British Columbia and the Alps, which often appear as an irregular texture rather than as recognizable topography. Vertical exaggeration, which is a graphical necessity when making small-scale landscape depictions, exacerbates the choppiness. When used with 3D and relief shading applications, unmodified GTOPO30 typically produces mountains with a choppy appearance. Resolution bumping is not a post-rendering touchup procedure. Although resolution bumping is accomplished in Photoshop, the well-known image editing application, the technique is used solely for modifying raw elevation data prior to creating 3D scenes and shaded relief. The technique alters digital elevation surfaces in a manner that allows rugged mountains to be depicted more legibly and with a more natural appearance compared to unmodified data. Resolution bumping is a technique in Adobe Photoshop for manipulating GTOPO30 and other small-scale digital elevation models (DEMs). In addition, Mac OSX users can export 16-bit DEMs from Photoshop 7.0 and CS in PGM format readable by Bryce using the free CartaPGM filter developed by Pascal Lamboley and Bernhard Jenny available here. 8), which now includes expanded support for 16-bit data, including layering, the DEM manipulation techniques described below are much easier to accomplish. Update - April 2004: With the release of Adobe Photoshop CS (v.
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