HP Latex 3000 Series

Possible causes
●
Uniform variations from tile to tile. When color changes uniformly it must be within the color
consistency specication; see Color consistency on page 31 for more details. Usually grays are much
more sensitive: dierences of much less than 2 dE 2000 may be visible, although other colors would not
show a dierence.
●
Sm
all color variation left to right. The tile itself looks uniform, but when putting it beside the adjacent
tile the
dierences become visible.
●
Local color variations. See Local color variations on page 326. Sometimes these defects become visible
only when printing tiles, showing in one of the tiles but not in the adjacent. They are also more visible
when printing grays.
Possible solutions
●
Try to ensure uniform printing of all tiles, and all tiles printed in the same run.
●
Rotate every other tile, to compensate for left to right dierences.
●
A
dding spit bars at both sides of the image helps overall, especially when there are local color
variations.
Edge roughness, text quality
The edges of objects may appear rough or blurred; this is especially noticeable in text.
There are ve possible causes:
●
Bleed: see Bleed, halo, wicking on page 325.
●
Printhead alignment. As each ink is deposited by two printheads of the same color, it is important that
the two printheads are correctly aligned. When a color is formed by a combination of inks, which is often
the case, it is also important that printheads of dierent colors are correctly aligned.
To check printhead alignment, print the printhead alignment diagnostics plot (see Printhead alignment
diagnostics plot on page 140), and ne-tune the alignment by identiying the oenders in the plot.
●
Substrate advance. Before trying to adjust any parameter, make the following checks:
◦
Check that no substrate-advance factor was set earlier that could prevent the substrate-advance
sensor from working correctly.
◦
Run the diagnostics to check that that the substrate-advance sensor is not dirty.
If the substrate advance is incorrectly adjusted, particularly if it is under-advancing, a dark line can
appear between passes. When the problem of line roughness or text quality applies to all colors and
appears in the substrate axis direction, it is likely to be related to incorrect substrate advance. Another
clue that could point to substrate advance as a cause is to observe that the defect is not constant,
appearing and disappearing along the print in the substrate axis.
ENWW Advanced print-quality troubleshooting 327