Ray K said:
When a color image contains blacks within it, do inkjet printers ever
use their black inks to reproduce the black, or is the black reproduced
strictly from the C, Y, and M inks?
It depends on the printer and the type of paper being printed on. For example,
the DeskJet 990 printer has a single pigmented black cartridge and a tri color
cartridge. In this printer black will be printed with the black cartridge when
printing on plain paper or matte photo paper. When printing on glossy paper
the black will be printed by mixing C, M and Y.
The more recent DeskJet printer such as the DeskJet 5650 or Photosmart 7760
support a photo cartridge which can be used in the place of the pigmented black
cartridge. The photo cartridge has light cyan, light magenta and photo black
which are used for printing on glossy media. Finally, the Photosmart 7960 has
an additional grayscale photo cartridge that has light gray, gray and photo
black inks.
Generally pigmented black inks are good for text but less suitable for glossy
photo media. Dye based black inks are typically used for photo printing.
Regards,
Bob Headrick, not speaking for my employer HP
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