Hi Jason, You can change (a) overall lighting and (b) lighting behavior of the surface itself. (a) Chimera uses two lights, "key" and "fill" where (by default) only the key light produces shiny highlights and shadows in raytraced result. http://www.cgl.ucsf.edu/chimera/docs/UsersGuide/raytracing.html You can adjust these lights' brightness, positions (directionality), and key/fill ratio in the Lighting tool (under Tools... Viewing Controls): http://www.cgl.ucsf.edu/chimera/docs/UsersGuide/sideview.html#lighting In general decreasing the key-to-fill ratio increases ambient illumination, so you could try that and/or increasing the overall brightness. Besides the lighting, it might help to adjust properties of the surface itself in Chimera. I assume you are showing an isosurface since I don't think transparent solids work with raytracing. Select the surface model such as with Ctrl-click or using the Model Panel, and then open the Selection Inspector (green button near bottom right corner). Inspect "Surface piece" - you will see some lighting-related parameters that can be adjusted. "lighting, transparency" dim => bright seems promising, although I admit I have not played with this parameter when raytracing. http://www.cgl.ucsf.edu/chimera/docs/UsersGuide/inspection.html#subsurfprop I hope this helps, Elaine ----- Elaine C. Meng, Ph.D. meng@cgl.ucsf.edu UCSF Computer Graphics Lab (Chimera team) and Babbitt Lab Department of Pharmaceutical Chemistry University of California, San Francisco http://www.cgl.ucsf.edu/home/meng/index.html On Aug 29, 2008, at 7:48 AM, odonnell@chem.fsu.edu wrote:

Hi. I'm seeking a tip or two on how to save an image of a semitransparent map with PovRay. Povray works fine, but the image of the semitransparent map it generates is much darker that it appears on the screen. Any advice would be much appreciated. -Jason