To export a 3D structure image select the Export Image item in the 3D Structure Viewer context menu or in the Display menu on the toolbar. The Export Image dialog will appear:
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Here you can browse for the file name, select the width and height of the image as well as its format: svg, png, ps, jpg, jpeg, tiff, tif, pdf, bmp or ppm. For jpg, jpeg formats the quality score parameter is available.