Konica Minolta micropress release 6 Manual Do Utilizador
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Generate extra gray levels
When HPS is enabled, this option produces exact number of gray levels set in
Limit number of distinct gray levels, even if the number exceeds the screen
frequency and device resolution limitation defined below. When HPS is
disabled, this option limits gray levels to the amount shown in Limit number of
distinct gray levels.
Conventional screens produce a maximum
number of gray levels based on the resolution
of the output device and screening frequency,
according to the expression:
E.g., a 2540 dpi device using a 100 lpi screen will
produce 646 gray levels.
Limit number of distinct gray levels, even if the number exceeds the screen
frequency and device resolution limitation defined below. When HPS is
disabled, this option limits gray levels to the amount shown in Limit number of
distinct gray levels.
Conventional screens produce a maximum
number of gray levels based on the resolution
of the output device and screening frequency,
according to the expression:
E.g., a 2540 dpi device using a 100 lpi screen will
produce 646 gray levels.
The number of gray levels needed is image-
dependent. A few flat tints behind text or in a simple diagram need no more
than a dozen levels. Do not enable extra grays solely to reproduce flat tints.
Continuous tone images from high-quality sources will respond best with up
to 256 gray levels. Graduated tints and blends require the greatest number
of levels, the minimum number being 256. Long vignettes or those using a
relatively short range of tints may require more. The rule of thumb is no single
step in a vignette should be more than 0.03 inches (0.75 mm) wide. Thus a
vignette from 20% to 70% tint that is 6 inches long requires at least 400 gray
levels. PostScript Language Level 3 allows up to 12-bit-per-channel images
(4096 gray levels). This is supported in the MicroPress RIP. It is very unlikely
that more than 1024 gray levels would be required. However, the RIP cannot
add more steps to an existing blend. Make sure the application creates the
blend with enough steps.
dependent. A few flat tints behind text or in a simple diagram need no more
than a dozen levels. Do not enable extra grays solely to reproduce flat tints.
Continuous tone images from high-quality sources will respond best with up
to 256 gray levels. Graduated tints and blends require the greatest number
of levels, the minimum number being 256. Long vignettes or those using a
relatively short range of tints may require more. The rule of thumb is no single
step in a vignette should be more than 0.03 inches (0.75 mm) wide. Thus a
vignette from 20% to 70% tint that is 6 inches long requires at least 400 gray
levels. PostScript Language Level 3 allows up to 12-bit-per-channel images
(4096 gray levels). This is supported in the MicroPress RIP. It is very unlikely
that more than 1024 gray levels would be required. However, the RIP cannot
add more steps to an existing blend. Make sure the application creates the
blend with enough steps.
Limit number of distinct gray levels to
Meaning changes based on the use of HPS.
When HPS is enabled
The entered value indicates the number of gray levels that will be produced.
When HPS is disabled
The value indicates the upper limit of gray levels that will be allowed. Some
devices may provide fewer gray levels than this limit. In this case, the lowest
number of gray values available will be used.
devices may provide fewer gray levels than this limit. In this case, the lowest
number of gray values available will be used.
Use Harlequin Precision Screening
Enables the use of HPS.
HPS Options…
HPS is a screening technology that ensures high-quality reproduction with any
screening option. Its features include:
screening option. Its features include:
• Generating extra gray levels that allow the use of higher screen frequencies
than the resolution would normally allow
• Reducing moiré patterning by using an adaptive screening technique that
adjusts each halftone dot so it is placed within a half pixel of its ideal location
• Determining how rosettes are formed in the image
Once enabled, HPS is a property of the page setup that uses the separation
style and applies to all pages printed with that page setup. Default HPS
settings were carefully chosen to provide good output to all PrintStations and
PrintLink connected devices.
style and applies to all pages printed with that page setup. Default HPS
settings were carefully chosen to provide good output to all PrintStations and
PrintLink connected devices.
Optimize for angle set
Reduces amount of memory HPS requires if the screen angle is pre-selected.
The default set (15, 75, 0, 45) is used for most work.
The default set (15, 75, 0, 45) is used for most work.
Snap angles to nearest 7.5
degrees
degrees
Snaps the pre-selected anglesto the nearest 7.5
°
Angle accuracy
Increasing angle accuracy gives more freedom in selecting a screen and may
reduce patterning on individual films, but may increase the likelihood of moiré.
For mono or non-overlapping spot color work, you can safely increase these
numbers. For process separated work, accept default values.
reduce patterning on individual films, but may increase the likelihood of moiré.
For mono or non-overlapping spot color work, you can safely increase these
numbers. For process separated work, accept default values.
Frequency accuracy
See Angle Accuracy.
Item
Definition
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screenfreq
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2540
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