On 22 Jan 2019, at 08:16, Georg Seifert <georg.seif...@gmx.de> wrote: > > Hi > > I have a app that can print black shapes (using normal cocoa view based > printing). A lot users complain that the printouts are not really black (the > printouts are rastered, so the color sync tries to simulate a CMJK black but > even thou that it is black already). > > We played around with the pdf made form the print dialog. Printing that from > Adobe Acrobat produces the same results. But Acrobat has an option to convert > the PDF to optimise it for Digital printing. It attaches a genericGrayscale > profile to the PDF. > > Does any have a hint what to do?
There’s often a printer setting on users’ printers to tell them to use (just) black ink. OTOH I think the problem is that Quartz by default prints using “rich black” (i.e. C+M+Y+K) rather than black, which is *sometimes* the right thing to do and makes sense in some respects, but when you really want *just black* it’s annoying. It’s probably also muddy looking on many inkjet printers. I don’t know whether it’s possible use color spaces to tell Quartz to use just plain black. It quite probably is (you might find using CMYK colours and just picking K will work, I don’t know; ColorSync could still interfere, mind). Kind regards, Alastair. -- http://alastairs-place.net _______________________________________________ Cocoa-dev mailing list (Cocoa-dev@lists.apple.com) Please do not post admin requests or moderator comments to the list. Contact the moderators at cocoa-dev-admins(at)lists.apple.com Help/Unsubscribe/Update your Subscription: https://lists.apple.com/mailman/options/cocoa-dev/archive%40mail-archive.com This email sent to arch...@mail-archive.com
