Re: Monitor calibration
Re: Monitor calibration
- Subject: Re: Monitor calibration
- From: email@hidden
- Date: Fri, 19 Oct 2001 08:20:58 EDT
In a message dated 10/18/01 7:22:18 PM, email@hidden writes:
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A working draft of the upcoming ISO 12646 (soft proof comparison of
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screen to print) recommends at least 100 cd/m2 and should be more than
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that.
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I had excellent match between the Cinema Display 130 cd/m2 and some of
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the
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viewing booths I reviewed for an upcoming PEI article. The Cinema Display's
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higher luminance level necessitated less compensation [dimming or dumbing
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down :) ] of the light booth to balance with the screen's perceived
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illumination. Luminance level does not effect your shadows it just
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increases your dynamic range from black to white. Personally, I think a
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bigger dynamic range is ideal.
Certainly agree with all that...
The bunk floating around about pushing the
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luminance level will prematurely age a monitor is a myth. I have been
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running an old Lacie 21/108 for several years at 100 cd/m2 and am still
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able
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to hit that target luminance level even with the monitor on every day --
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sadly, I still work weekends :(
Its not "bunk" it's just difficult to say if a monitor fails due to the guns
dropping off, or the phosphors fading; due to the interaction of the two.
Phosphors fade at pretty much the same rate in all CRTs at a given luminance
level, and that fade rate increases as that level gets higher. If your guns
are stronger, or last longer, then they will continue to illuminate those
weaker phosphors successfully. If they aren't... well, running the device at
a lower luminance level *would* have kept this failure from occuring so soon,
by reducing the rate of phosphor fade... but one could equally blame the
guns... but the only factors you have control of, once you have purchased a
given monitor, are the luminance level you run it at, and the number of hours
per week you burn it. Oh, there is one other factor that comes to mind for
CRTs: whether you optimize the display area to fill out the screen of the
monitor. Doing this does nothing to the phosphors (except age the ones at the
edges too), but it increases the load on the guns significantly for a given
luminance level, at the inverse square formula for luminance over area.
So the fact that one monitor has lasted for several years at medium luminance
levels does not "prove" that higher luminance levels don't decay phosphors
faster... any more than one old lady still smoking proves that tobacco
doesn't cause lung cancer.
C. David Tobie
Design Cooperative
email@hidden