Gerber OMEGA CP, Справочное руководство

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The following chart provides LPI guidelines for Gerber thermal printers based on the size of the
job and image/fill type.
Output size: 5.8 inches or less Output size: 5.8 inches or more
Photographs: 55 to 70 LPI Photographs: 45 to 60 LPI
Line art: 70 to 90 LPI Line art: 70 to 90 LPI
Solid fill: 70 to 90 LPI Solid fill: 70 to 90 LPI
Linear/radial fill: 42 to 70 LPI Linear/radial fill: 35 to 54 LPI
Your LPI setting may be too high (the dots are too small) if at the intended viewing distance, the
output looks blotchy or posterized in highlighted areas such as a person’s cheek, or
linear/radial fills have bands.
Your LPI setting may be too low (the dots are too big) if at the intended viewing distance, the
output appears coarse or granular.
Choosing halftones for the MAXX 2
OMEGA software lets you choose different halftone types and sizes. In general, the GERBER
MAXX 2 shows fewer seams when jobs are printed with GerberTone or another larger halftone
type. If jobs still display seams when using GerberTone, try using Classical Dot halftone type.
Most seaming – even on difficult colors – disappears when using Classical Dot halftone between
18 and 42.4 lines per inch.
To minimize conspicuous seams follow these recommended steps:
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First, clean the printhead as described in the MAXX 2 Owner’s Guide.
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Second, when possible, use the optimized MAXX GerberTone halftone for the job.
When sending the job to the MAXX 2, allow GSPPlot to automatically substitute
existing halftones with optimized halftones.
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If the GerberTone MAXX optimized halftones are unacceptable, use a halftone type
with larger dots. Try Classical Dot halftone with a line per inch setting of 18 to 26.5
lines per inch. These larger halftone dots are often much more pleasing than people
anticipate. The human eye assimilates the larger dots from a viewing distance of 6 to
10 feet. This tends to be more acceptable than having seam lines that are visible from
as far away as 25 feet, which can occur when using smaller halftone dots.
OMEGA provides several methods for choosing halftones for a job. The original assignment of
halftones is done in the Assign Colors and Image Fill dialog boxes of Composer. If you know
that the halftones in the job are not optimal, you can substitute the existing halftones after the
job is sent to GSPPlot. Alternately, you can send a job to GSPPlot and allow it to evaluate the
existing halftones and replace them with optimized halftones automatically.
Tip: If you have a large job and are unsure of the appearance of the printed halftone you can
print a small section of the print to see the results. In GSPPlot add several vertical and
horizontal panel lines to surround a small area of the job. Select only the panel you wish to