I'm interested in more recent approaches to shaded reliefs than Imhof. Lionel's pointer to the rather excellent shaded relief website is a good start. The exisiting 9 dialog box gives us no better functionality of just about any other GIS package. My challenge is to render pseudo realistic sea floors, where delicate features must be observable, without vastly exagerating large changes in depths. My approach has been to prepare bathy raster data in MFD8, using it to extract and export resampled and smoothed black/white shaded relief, and the original DEM. I then create a Terrain Texture Shade (Leyland Brown) use a combination of Photoshop, or more recently, QGIS layer blending tools to blend the black/white relief and the hypso tinted terrain texture shade to produce a more subtle relief with detail intact. Attached is a sample of such bathymetry. The bight in the top centre of the image has rippled scour depressions (RSDs) They are charactarised by change in depth of around 0.5m To the south of that bight are a pair of 100m deep scour holes, with exposed limestone walls. The presence of the RSDs and the holes are of equal cartographic importance. A simple shaded relief, like that generated by 8 and 9 will not produce such output. So what would I like to see in nine? Slider control on z value exageration, slider control on azimuth, slider control on height, with real time preview. Implement Leland Brown's Terrain Texture Shader algorithm (a dialog box with a weighting slider that ranges from relief to texture shading) Layer blending tools (like QGIS, PS, or other image editing tools) Localised directional shading would be pretty nice, but layer blending can do that in a work around. Attachments: Texture shade.jpg
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