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Name
Data Type
Description
AngleMap are specified, the angle is determined by the default of
the selected ScreeningFamily.
AngleMap ?
New in JDF 1.1
string
Specifies the mapping of the angle of the screen to the angle of a
different separation when AM screening is used, e.g., a spot color
that has the same screening angle as the cyan separation is specified
by AngleMap = Cyan. In FM screening, AngleMap specifies the
mapping of the separation specific screen functions, e.g. threshold
arrays.
[RP504]
Only one of Angle or AngleMap may be specified.
This mapping is not transitive, so, when Separation already
specifies a color with a known default
7
, it specifies the angle of the
separation defined by AngleMap prior to that separation being
mapped, e.g., the following example specifies that Black should be
mapped to the Cyan default separation and Cyan to the Black
default separation. The third line maps Spot1 to Magenta.
<ScreenSelector AngleMap=”Black”
Separation=”Cyan”/>
<ScreenSelector AngleMap=”Cyan”
Separation=”Black”/>
<ScreenSelector AngleMap=”Magenta”
Separation=”Spot1”/>
[RP505]
AngleSecondary ?
New in JDF 1.2
double
Allows optional specification of the second angle of the screen
when AM dot screening (ScreeningType = “AMDot”) is used,
otherwise AngleSecondary is ignored. If Angle is not supplied,
AngleSecondary is ignored.
AM screens may be dot screens or line screens, or they may be a
combination of these. In a particular instances, two angle values
(Angle and AngleSecondary) may be used to specify the
directions of two fundamental AM dot screen frequency
components.
Commonly, if only Angle is supplied, the frequency components
are orthogonal, i.e., angle1=angle2+90, or the second angle is
implementation dependent on the first. For backwards
compatibility with JDF/1.1, if only Angle (and not
AngleSecondary) is supplied, the second angle is system
specified.
Either Angle (with AngleSecondary) or AngleMap may be
specified, but not both. If neither Angle nor AngleMap are
specified, the angle is determined by the default of the selected
ScreeningFamily.
[RP506]
DotSize ?
New in JDF 1.1
double
Specifies the dot size of the screen in micron[µm] when FM
screening (ScreeningType = “FM” or “Adaptive”) is used.
Frequency ?
Clarified in JDF 1.2
double
Specifies the halftone screen frequency in lines per inch (lpi), when
AM screening is used, otherwise Frequency is ignored.
With some screens, frequency may change as a function of gray
level. In this case, the Frequency value is interpreted for a
midtone (50%) gray level.
If Frequency is not specified, the frequency is determined by the
y the
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In general this will be a CMYK process color, but it can also be another process color, e.g., HexaChrome
TM
