On Tue, 9 Dec 2008, lvyuan zhang wrote:

Hi, I'm making my protein ribbons partially transparent by changing the alpha value in color editor. I tried a=0.2 and a=0.05, and I found that after raytracing, there is no difference between these two. Isn't a=0.05 supposed to be more transparent? Is this a bug or something is wrong with some settings in chimera that I don't know? Thanks a lot first!

Cheers! Luyuan Zhang

POV-Ray uses a different lighting model than chimera, so the lighting will never match exactly. Chimera colors are currently converted to POV-Ray rgbf colors. I don't recall why that choice was made, but changing to rgbt colors appears to mimic chimera better. I will make that change and it will appear in the next daily build. If you want to test out the change right now, change your POV-Ray Options so that "Keep POV-Ray input files" is true, then edit the resulting image.pov file and replace all of the rgbf's with rgbt's, and rerun POV-Ray with: CHIMERA/bin/povray +Iimage.pov +Oimage.png image.ini Please let me know how you like the new version, Greg Couch UCSF Computer Graphics Lab