any secrets printing only a section from a card?

[Tiemo Hollmann TB]

Hello,

LC 8.1.4, Win 10. (Same with LC 6-9) When printing a whole card with just
"print card" everything of the card is being printed fine, only stretched to
the papersize.

But when trying to print only a part of the  card by "print card from
myLeftTop to myRightBottom into page Rect" I never get the wanted rectangle
being printed into the pageRect. It is always clipped somewhere and only a
small part of the wanted rectangle is being printed. I have also tried to
set the printpapersize and printmargins and fiddled around with different
rectangle sizes, but didn't got the wanted section.

Are there any secret conversion factors, when printing "from to"?

Thanks for any hint

Tiemo