This driver was written for use with PCL 3 compatible printers which can print using *four* inks at the same time without having to change cartridges. This includes printers like the HP 880C or the HP 550C. It *does not* include the HP 500C or the HP 420C. Specifically, this driver was designed for printers which follow the CMYK colour model.
Shingling is a technique which works by interlacing individual printing passes, thereby increasing the amount of ink that hits the paper. Colour will be packed much denser with this technique, but printing time will increase since the printer`s head will have to make up to four passes on the same few lines to be printed.
Depletion is an intelligent ink reduction technique. If a lot of ink hits the paper, the paper may be unable to absorb it. In severe cases ink may even leak into other areas of the paper.
With the HP_DeskJet_CMYK driver shingling and depletion are controlled by the print density settings:
1-3: No depletion, no shingling
4: 25% depletion, no shingling
5: 25% depletion, 50% shingling
6: 25% depletion, 25% shingling
7: No depletion, 25% shingling
Printing quality will increase as you increase the density. So will the time it takes to print. The printing resolution will increase, too: with densities 4-7 300 DPI will be used for printing.
Without applying gamma correction, printouts will come out too dark. The HP_DeskJet_CMYK driver can apply gamma correction, depending on the threshold settings. Threshold setting 1 will apply no gamma correction. Threshold settings 2-15 will make the printout progressively brighter. As experience shows, quality is best around threshold value 10.
