I love this conversation, and I love coming back to it again and again as we seem to do, because even after reading all the responses over and over again, I never can quite figure out exactly what the answer is — or even exactly what y'all are saying the answer is.
Here, for example, the illustration says "Booth dimmed 50% to match LCD" and "LCD with proper luminance calibration ... to match booth." So which is it? Do we change the luminance of the monitor to match the print (in a given viewing light), or do we change the print viewing/assessment light to match the monitor?
The part that buffaloes me particularly is that I can never make sense of the notion of changing the light on the print in the assessment context to match the monitor. It seems to me that, except perhaps in galleries or in our own controlled environments, prints can rarely be expected to be viewed by our customers in precisely the same light that we choose to evaluate them in. That suggests to me in turn that we should choose print assessment lighting environments that come as close as possible to our reasonable predictions of the range of lighting that we expect the print ultimately to find a home in, or at least that come as close as possible to letting us make a good judgment of whether the print is going to hold up and be successful in that range of environments.
Now it strikes me that for the most part this ought to be a reasonably standard color temp and lighting level. I think of the example of magazine covers. They're viewed in everything from dark waiting rooms to harsh airport newstand lighting — but how often do you find yourself looking at a magazine cover and thinking "They printed that too dark" or "Wow, Newsweek is really looking washed out and reddish this week." This tells me that there must be a brightness and color temperature sweet spot (or at least a very narrow range) out there for print assessment lighting that is simply right[/b]. Not right for you, or right for me, but just right, period.
And so I conclude that we don't — ever — change our print viewing light to match our monitors. We do change it to get to that sweet spot, so that we can have some level of confidence that the judgment we make about the print in that light is going to hold up when the print arrives at, and basks in the light of, its final destination. And, having found that sweet spot for viewing the print, then we adjust the luminance of the monitor[/b] to match the print.
Throw into this mix the fact that our subjective judgment of the image on the monitor is influenced by the ambient light in our respective work environments, and you're back to having a wide variation in "correct" monitor luminance settings, but a very narrow range of "correct" lighting for assessing prints.