23
Slope Calibration for the
IQ150 & IQ200 Densitometers
The SLOPE mode can bias the calibration of the IQ150 or IQ200 so that
the displayed density will match that of another densitometer.
Densitometers from different manufacturers have differing optical
characteristics; therefore they do not always display the same density
values across their full operating range. When the slope calibration has
been selected, the IQ150 or 200 applies a multiplier to every reading to
compensate for these differences. Following pictures are EXAMPLES
only.
To enter the slope values, press the [SLOPE] key. When this mode is first
entered, the values of the slope multipliers will be displayed.
If you wish to change the slope of any color channel, read a sample
patch of that color, preferably on the main process colors of the control
strip or the T-ref. (Retain the sample in a safe place when this session
concludes, so that you can return to it for future slope sessions.) After you
read the patch, its color and density will be displayed. At this time you
can change the displayed density value by pressing the [+] or [-] key until
the desired value is attained. To the right of the density display will
appear the number signifying the slope multiplier. (It will be a slight
variation above or below 1.000, for examples: 0.950 or 1.050) Do not use
numbers that are extreme amounts in attempts to compensate for a defect.
This number to the right of the density reading is the multiplying factor
that is used to bias the density value to its new value. Once the desired
density value has been attained press the [SAVE] key. The slope value
will be thereby stored and will be used on subsequent readings.
