Re: Monitor calibration
Re: Monitor calibration
- Subject: Re: Monitor calibration
- From: email@hidden (Anthony Sanna)
- Date: Thu, 18 Oct 2001 17:15:54 -0500
>
You said it, the shadow "appeared" too open. Do you know in actuality the
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device-dependent (RGB or CMYK) data remained the same accross the two
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monitors or that it varied because of the difference in absolute brightness
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between the two monitors? I would venture to say that it should not happen.
We were dealing with hypotheticals, here. Jack's in California and I'm
in Wisconsin, but to answer your question, the color values are not the
variable, here, but rather what we see on screen - or more precisely,
what visual information we are basing our color adjustments on. IOW,
would shadow detail "appear" more open on a brighter display, and from
that "appearance" could the wrong assumptions be made when correcting the
file.
Here's a more extreme - and real life - example. A couple of years ago,
I had a b&w doutone job running at a local engraver/printer. His shop
was an old-line engraving operation that had recently installed a press
to generate work for his real bread & butter business, making film. He
didn't have much experience with doutones, but said that he could do it
(Hey! It's two less colors. How hard could it be?). When I got the
separated file back it was a muddy mess. I dropped by his shop to talk
to him about it, and he sat me in front of one of the monitors, opened
the file, and turned the brightness all the way up (and I mean WAY UP).
"SEE!", he said. "There's lots of detail in the shadows." Then he
turned the brightness down until the screen was mostly dark gray, and
continued "...and look at that highlight detail!"
In the end I opted to let him run the job as a CMYK b&w - what he wanted
to do in the first place, and what he had experience in doing. It turned
out ok, the client was happy, and I was off the hook. Maybe he was right
and the job would have printed just fine - filled with detail from shadow
to highlights. I'll never know, but I was unwilling to find out on
someone else's job. Watching him twirl the brightness knob gave me the
willies.
So..... Although we're talking about a brightness variation that's a
fraction of the above example, could the assessment of shadow tones, and
a subsequent decision to open them up, be affected by the brightness of
the monitor? ...or, stating it differently, is there a monitor
brightness standard or recommendation - similar to color temperature,
let's say.
Years ago I had a PressView. When it was new, calibrating with the
ProSense puck was a simple lick, stick, & click operation resulting in a
simple "monitor has been calibrated to D50" dialog (or something like
that). As it aged, however, the message changed along the lines of
"monitor has been calibrated to D50, but monitor brightness failed - 72
cd/m2". When I called Radius tech support about this, they said that it
really made no difference as long as critical work was being done in a
darkened room.
THE QUESTION: Does this mean that monitor brightness has more to do with
environment adaptation of the eye, than it does to any set brightness
standard? OR would Jack, sitting in a dark room in California looking at
an image in Photoshop displayed on a calibrated monitor set at 75cd/m2,
make different decisions about the file than I would, sitting in a dark
room in Wisconsin looking at the same image displayed on a calibrated
monitor set at 90cd/m2? Oh... BTW, we both think alike.
>
But, isn't it odd, Anthony, that your old faithfull PressView at 70 cd/m2
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and your Sony at a blazing 120 cd/m2 are both "normalized", internally by
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profile makers, to a Y=100 for usage in an ICC workflow?
I'm not sure I understand this one. Explain, please.
Tony
Anthony R. Sanna
Vice-President
SACO Foods, Inc.
6120 University Avenue
Middleton, Wisconsin 53562 USA
email@hidden
www.sacofoods.com
1-800-373-7226
(608) 238-9101
(608) 238-8149 - fax