About eliminating artifacts when processing CT/LW files
Raster-based files can be prone to artifacts on the final output without
proper page preparation. (An artifact is an unexpected element, usually
a single-pixel black or white line.) High-resolution loose page proofs
may not show artifacts, although a high-resolution imposition proof
often does. Here are some recommendations for reducing artifacts.
Ensure that LW and output resolution match when imaging
Before submitting pages for final output, make sure that the LW
resolution matches the final output device resolution. If the LW
resolution doesn't match the output device resolution, Prinergy must
resample the LW data at the output stage, which may introduce
artifacts.
You can set the LW output resolution on a Brisque when creating CT/
LW pages. For example, if you are outputting to a 2400 dpi Kodak
Trendsetter platesetter, RIP your pages to CT/LW with the LW
resolution set at 2400.0 dpi (94.48819 dpm). Or, you can set the LW
by refining the CT/LW file with a refine process template with the
CEPSConversion JTP enabled and set to resample at the appropriate
LW resolution. Use the Prinergy Process Template Editor to create or
edit a refine process template.
RIPing to the device resolution has no visible impact on final output and
is recommended for use with all CT/LW files. Setting the LW
resolution on a Brisque, that is, creating CT/LW at the correct
resolution, is preferable to setting it in Prinergy where you resample to
correct resolution at the conversion stage. Resampling to at the
conversion stage may have a slight visible impact, since resampling
errors may occur.
Avoid running Copydot pages through the Brisque
A copydot page that was run through the Brisque is susceptible to
moiré artifacts unless extreme care is taken.
Using the CEPS JTP
LW resolution
: If possible, RIP LW to 2400 dpi (94.48819 dpm).
Always resample at the CEPS JTP stage of your refine process template
to ensure the resolution is correct.
Using PDF2Go on Brisque version 3
CT resolution
: Should be set to a dpi that converts easily into
PostScript points. Recommended settings in dpi are: 300 dpi (11.81102
dpm), 320, 360, 375, 400, 450, 480, 500, 576, 600, 720, 750, and
800. This option may have a very slight negative impact on your final
About eliminating artifacts when processing CT/LW files
159
