What is choke used for?
Choke is used to shrink the white layer if there is a misalignment between the color layer and the white layer in the printed output when using Underflood or Overflood modes. Examples:
How can choke be applied?
Using the IPS. There is new functionality in the Job Properties panel that allows choke to be applied.The options are:
1. Choke white ink
a. If disabled (default), choke is not applied, and the white layer is not shrunk. It is maintained as in the original image.
b. If enabled, choke will be applied, and some pixels will be removed from the white layer. The remaining choke settings will need to be defined.
2. Smart choke
a. If disabled (default), choke will be applied to the full white layer.
NOTE: Using this option, small text and details might disappear.
b. If enabled, choke will only be applied in the areas of the image where there is color over/under the white layer. It will not be applied if only white is present. In addition, small text and details will be protected and will not disappear from the image.
3. Pixels to shrink
This is the number of pixels to remove in the white layer. HP recommends starting with 4 pixels (600 dpi) and then to adjust if necessary.
NOTE: The final area removed from the white layer is relative to image resolution.
Example: 2 pixels at 300 dpi is equivalent to 4 pixels at 600 dpi.
1. High opacity white print modes might require greater shrinking than fast white print modes.
Example: W260 (right) and W60 (left) with the same number of pixels choked.
2. It is possible that choke may work very well in some areas of the plot, but that the misalignment is not completely removed in other areas.
- Quality of the printhead alignment.
- Media deformation.
- Print mode used.