Michael Schulz wrote:
The printer is a HPDesignJet 10 ps. The behavior of the printer shows visually a slight red color cast which become obviously in skin tones. The results measuring the FOGRA-strip_v2 are within the norm (2007).
The red cast might be a metamerism issue. If I remember correctly, the HPDesignJet 10 ps inks are very susceptible to metamerism failures. Therefore it's important to view the prints under standard lighting conditions (D50 viewing booth or the like).