User Manual

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8. Where is my software serial number?
Your serial number will be either 17 or 18 digits long; depending on your
application. It is located on the inside of your box under the hardware
device. Please do not confuse this with the hardware serial number for
your hardware device(s).
9. Why don’t my monitors look the same after calibration?
Visual observation of two monitors sitting side-by-side will never appear to
match. Even if they are the same type, make and model, two displays will
have subtle differences that are readily discerned in side-by-side
comparison, but become negligible when each display is viewed
separately.
Comparing a CRT monitor to an LCD monitor will be even less rewarding
because of the inherent differences in display technology. In a side-by-
side comparison between a CRT and an LCD, the LCD will always be
perceived as 'brighter' and having 'higher contrast'. This is because the
peak luminance of an LCD is typically about twice that of a CRT, even
when you calibrate both monitors to have the same Gamma and White
Point.
To compound the effect, the organic eye-brain colorimeter (aka human
color perception) causes one kind of difference to be perceived as if it
were another kind of difference. Even if two samples have the same color
but different luminance, they will be perceived as also different in color.
Thus, when you calibrate a CRT and an LCD to the same Gamma and
White Point and place the monitors next to each other, the fact that the
LCD is twice as bright will cause them to appear different in color even if
an instrument records identical chromaticities.
The human visual system has another powerful feature, referred to as
'adaptation'. For example, if you move from a room with incandescent
lighting to one that is lit with fluorescent tubes, you will initially perceive
white objects as having a bluish cast, and possibly brighter than they
were. However, after a few minutes, your visual system 'adapts' to the
new environment and your 'adapted' perception is that white objects are
merely white.
Visual adaptation allows us to use two different technologies, like CRT
and LCD, to view the same image file with similar perception. However, if
you place two different monitors side-by-side and view them
simultaneously, the visual system cannot adapt to both simultaneously.
They will always appear different (in color, luminance and contrast) due to
that very sensitive 'comparison' function of human visual perception.