Cmetzendorf wrote:
As for the others where this was tested. So what could be the reason? Preview using the graphics hardware - Intel HD Graphics 3000 512 MB - in strange ways?
Possibly.
I guess there is a way to test that hypothesis, if you have at least temporary access to another mac (that does not show the problem with these PDF files).
Start your mac in Target Disk Mode, and use it to boot the other mac (using a Thunderbolt or Firewire cable, depending on the mac models in question).
This way you would be using your own mac's OS and user accounts, but running on the other mac's hardware, including the graphics card.
If the pdf look fine, then it pretty much guarantees that it is related to Preview and your mac's graphics card.
If they show black, then it is something in your mac's software installation.
(You can also do the same test in reverse, in which case black pdf means something with the graphics card.)