Making a "Smoother" Image When rendering a landscape, even at Polygon size "1", you will often see small triangles in the close up portions of the picture. This is because the USGS data used to make the Vistapro DEM files is made up of elevation points that are about 30 meters apart. When that distance is more than 1 pixel wide, then that point in the landscape will render as a triangular block. There are several methods of hiding these blocks when rendering. Blend: Blending smooths the changes in color from polygon to polygon, causing the small polygons to be less apparent, especially in the distance. To use blending, click on the Blend button, on the Middle Control Panel, before you render a picture. The button will remain depressed until you again click on it to disable it. Gouraud Shading: Gouraud Shading smooths the boundary between polygons, making it much less apparent that they are even there. It also eliminates sharp transitions from one color to another, giving the image more of the quality of an artist's rendition. Gouraud Shading may be enabled by pressing the GShade button, in the Main Lower Control Panel, before rendering a picture. The button will remain depressed until you again click on it to disable it. Dither: There are two methods of dithering available with Vistapro. The first, using the Dither button causes a blending of the elevation colors, reducing the sharpness of the snow and tree lines. This can be changed by clicking on the numerical gadget below the word Dither in the Middle Control Panel, and entering a new value. Larger values result in more dithering, smaller values result in less dithering. The second method is called pixel dithering, mixing slightly different colored pixels to simulate more colors. This can be set by clicking on the numerical gadget below the PDthr button on the Main Lower Control Panel, and entering a new value. Larger values result in more dithering, smaller values result in less dithering. You can add so much dithering so as to make the image entirely unrecognizable.