[Chimera-users] a problem with silhouettes

[Alja Oblak]

Dear Chimera users, 

I am trying to create an image for a publication using Chimera 1.6.1.
Whenever I turn on "silhouette" dark spots appear on the screen and on the saved image. They seem totally random but they move along with the structure when rotated. When I zoom on them they look like small "umbrella-shaped" discs. The "show shadows" option is turned off.
Does anybody know what are those spots and how to get rid of them?

Thank you very much for any help.

Regards, 
Alja Oblak