Konica Minolta micropress release 6 Manuel D’Utilisation

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These are linearization curves that ensure a 1:1 
response between gray values requested in a job and 
halftone values printed. Used to correct halftone 
printers such as BiLevel, QuadLevel, and Mono-
chrome. The graph shows an example of a typical 
response seen from a non-linearized imagesetter.
The curved line is the imagesetter’s response. The 
straight line is the desired 1:1 response. If a 50% tint 
is sent to the imagesetter, a 30% tint is produced on 
paper. To solve this problem, a linearization curve is 
loaded into the RIP that defines the screen percent-
age to create based on the screen percentage 
requested. In this example, the RIP would create a 
higher screen percentage (60-70%) which, when 
printed, produces a 50% screen on paper. Note: 
Con-
tinuous tone devices (Contone, Gray) are linearized using Gammatic. Since “Tone Curves” require a 
calibration curve to enable their use, “EnableToneCurves” is provided for Contone and Gray printers.
Tone Curves
Tone Curves are “adjustment curves” that modify the output of a printer currently using a cal-
ibration set. Used with both halftone and contone printers. For example, if a monochrome 
printer using the “Linear Monochrome” calibration set produces dark output, apply the Tone 
Curve “Light+10%” to lighten output by 10%. Where it may seem effectively the same as 
modifying the calibration set, the power of Tone Curves is five-fold:
Available to all printer types.
Curve effect is the same, regardless of printer type.
Standard calibration sets (linearization curves) remain unaffected, providing a consis-
tent baseline from which to work.
Since the printer is already linearized using the calibration set, Tone Curve values are 
absolute, meaning a 5% increase in tone curve value will create a 5% decrease on 
paper.
Can be used with the ICC Profile Processor to provide color adjustment capability and 
color matching.
Using Tone Curves with Contone or Gray Printers: Contone and Gray printers are linear-
ized by Gammatic and do not require a calibration set. However, since Tone Curves are only 
effective when a calibration set is loaded, a special calibration set called "EnableTone-
Curves" is loaded to enable Tone Curve use with these printers.
When to use Tone Curves: A Tone Curve modifies all jobs sent through the RIP. For half-
tone printers, this is the only method available for adjusting jobs. Contone or gray devices 
can use both Tone Curves and PSM ColorCurves. ColorCurves are applied to individual Pos-
tRipped jobs so they don't affect other jobs or jobs being sent through the system (see the 
PrintStation Manager Reference Manual). If you consistently use a particular ColorCurve for 
adjustment, consider creating its Tone Curve equivalent and load it into the RIP to be auto-
matically applied.