Robert Krawitz, leader of the Gutenprint project has answered now. He tells that this is probably a generic bug in Gutenprint and that he will check it.
He also tells that for the time being you should try: If black is OK, try reducing Gamma If black is too light, too, raise the Density -- print driver brightness control causes bad print https://bugs.launchpad.net/bugs/128428 You received this bug notification because you are a member of Ubuntu Bugs, which is the bug contact for Ubuntu. -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
