Re: Monitor Calibration
Re: Monitor Calibration
- Subject: Re: Monitor Calibration
- From: Dan Reid <email@hidden>
- Date: Wed, 13 Dec 2000 12:37:03 -0700
on 12/12/00 12:24 PM, Anthony Sanna at email@hidden wrote:
>
> Most have experienced dingy yellow monitors not because of the white
>
> point being calibrated to 5000K but because the luminance level is reduced
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> to an unacceptable level when compared to a light box. I have had excellent
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> results with 5000K white point and 100cd/m2 level.
>
>
Well then, this begs the question of what the appropriate luminance level
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should be. It was never much of a concern before, since most of us were
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probably fighting for every lumen we could get on our calibrated
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monitors. I know that as mine aged I was continually shrinking the
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screen dimension to keep it's head above the 75 cd/m2 PressView minimum
>
standard.
I shoot for 100cd/m2 luminance level. ISO 3664 (Viewing Conditions)
recommends the luminance be ". . .shall be greater than 75cd/m2 and should
be greater than 100 cd/m2 using a D65 white point."
>
But now I have a new Sony GDM-F500R, a DTP 92USB, and Pre/OptiCal, and
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even with the screen dimensions to-the-max (about a 1/4" border), when
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the red gun is run at 100% for the PreCal settings, my final luminance is
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around 110 cd/m2 at D50. If I do the same for D65, I end up in the 125
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cd/m2 range. Right now my red gun is running at 85% to give me a
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luminance of 90 cd/m2 at D65. Why 90 cd/m2? Because Bruce recommended
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85 cd/m2 and I just couldn't bring myself to drop it that low. So what
>
is the best setting?
What ever luminance level is closest to your light booth. Obviously you want
to use a dimmer on the booth and increase the luminance level on the monitor
until there isn't a strong difference in comparing. I like to keep the booth
to the side or behind me so I must physically turn around. This gives my
eyes a moment to adjust to difference in intensity.
>
>
A second question would be: How (and where) should you set the luminance?
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What I've been doing in PreCal/Optical is to fiddle with the gun levels
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in PreCal to get luminance level I'm looking for BEFORE running OptiCal.
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So now, if I check my monitor settings, my gains are set to 85/75/75%,
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and brightness/contrast are at 49/99%. Now I realize that these numbers
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are meaningful only to my monitor setup, but I can also calibrate to the
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same color temperature and luminance by setting the gains at 100/90/90%
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in PreCal and arriving at a different brightness/contrast setting in
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OptiCal - 34/90% let's say. So what IS the best way, and what IS the
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most appropriate luminance when dealing with these modern, bright
>
monitors?
As I said before I drive the Red gun at 100% and calibrate the other guns to
meet my target white point. If I have too much luminance output (which you
can note while in PreCal) then I decrease my contrast setting until I reach
the desired luminance level. I may have to adjust the guns again but usually
only slightly. Then go to Optical and run through the full calibration and
characterization process.
--
Dan B. Reid
RENAISSANCE PHOTOGRAPHIC IMAGING
Color Imaging Solutions Provider
http://www.rpimaging.com | email@hidden
Toll Free: (866) RGB-CMYK [ 866-742-2695 ]