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What is the Best Multi-Monitor Calibration Tool?
sojourndeath asks: "I am looking for a good way to calibrate multiple monitors (30-40), so that their color looks similar? It seems like everything I find is for profiling your monitor to your printer and scanner. I need to be able to have a bunch of users see the same color on any monitor? Does anyone have a good, accurate way of doing this?"
> I need to be able to have a bunch of users see the same color on any monitor?
If you wanted to have the _same_ user see the same color the same way on
different monitors, that is theoretically achievable with good quality CRTs,
assuming you can put them in identical settings and so on.
But with different users, there is going to be a difference in perception.
Some people see *significantly* more color depth than others, for instance.
Also, some people's retinas are more sensitive to light than others, so they
have most of their color resolution in the darker ranges; other people have
eyes less sensitive to light and distinguish brighter colors better.
I've discovered that most of my coworkers can't tell #305050 from #294D4A,
even when they're side by side. To me, they're noticeably different in
character, and if you show me one of them by itself, I know which of the
two it is. (This is probably attributable more to the difference in
blue/green balance than the slight variation in brightness, but anyway, I
can tell.) One time I asked for a coworker's opinion on the brightness of
a certain background, and she said it was too dark, so I grabbed the V
slider (in Inkscape) and lightened it up a bit, then looked at her; she
obviously didn't realize I'd changed it at all. So I dragged the slider
over a bit more, and a bit more... after a bit I asked her how that was,
and her response clearly indicated she still didn't see a difference. I'd
changed it by probably 20 or 30 units per channel. (I quit asking for her
opinion on colors after that.) She's an extreme case, obviously, but the
basic phenomenon is universal: people don't all have the same eyes.
Cut that out, or I will ship you to Norilsk in a box.
I've discovered that most of my coworkers can't tell #305050 from #294D4A,
even when they're side by side.
Uh, this depends on the monitor you're using as well.
Most of the time people are just just lazy, they're not really paying attention to the differences because they don't care. Those colors look similar enough that most people just ignore the differences. That doesn't mean they can't see the difference, they just don't want to.
This is one of those ambiguous uses of the English language.
When I read it, I took it to mean,
I want any given user out of a set of users to see the same colors on all monitors.
It appears that you took it to mean,
I want every user out of a set of users to see the same color on any single (or) on all monitors.
Since the phosphers are fairly standard from monitor to monitor in the same manufacturing run (ie, red gives of a certian wavelength across a range of monitors) then it's easily possible to make it so that any group of monitors made at the same time produce the same color regardless of the user's perception. Blue may look different for user A than for user B, but user A will see that same blue on the other monitor that they saw on the first, and user B will see the same blue they saw on the second monitor that they saw on the first.
I imagine that phospher emission wavelength is fairly standard within a narrow range, but I suspect that different models, even within the same original manufacturer, may have slight variations in emission. Therefore to get the best matching color you'd really need to purchase high quality (meant for imaging applications) monitors from the same manufacturer at the same time. You can usually tell that they're high quality and meant for imaging applications by inflated cost and included calibration device, though it's not universally true (ie, if you don't know any better, then this is about as close as you're going to get without a lot more research)
-Adam
I suppose he's building something like a multi-monitor wall or an art installation where multiple monitors form a single or repetitive image. In that case a monitor with different color reproduction would stick out like a bad pixel on a TFT screen.
Heh, well said - it's quite surprising how many crap comments there are on this story, you'd think more pro photographers/designers (or their IT techs) would chip in with some decent advise on colour workflow and calibrating to a specific target. Though, as is usual on Ask Slashdot, the submitter didn't provide many details, so it's harder to give him specific information to help him find a solution.
With regards to colorimeters -- these'll all allow you to calibrate to a "baseline" rather than the best that each device can display -- I've got a Spyder (mk.1) and it's not too bad, though the new ones look much better (increased sensitivity) - though no-one's mentioned so far that the software that comes with these (PhotoCal or OptiCal) requires a seperate licence for each machine they're installed on, so at 30-40 monitors it's not going to be as cheap as it first appears. The GretagMacBeth stuff seems like another good choice (e.g. the Eye-One), as do the Monaco/X-Rite calibration tools, but they're more expensive. Ideally you go for a solution that's not just limited to calibrating screens, but can do printers as well, but again it'll cost more (it's usually worth it though - you might as well do the entire loop while you're at it). Or, if he's really serious about it, standardise on the same model of monitor, such as the Sony Artisan (with built-in calibration that actually adjusts the CRT guns, rather than just generate a profile).
Like another poster said, lighting's also an issue, too; hooding the monitors to minimise reflections is usually a good idea, and standardising on specific lighting such as Just Normlicht fluorescent tubes or Solux halogen bulbs (fed with a specific regulated voltage) helps immensely.
Once upon a time we used to adjust 20+ monitors in a television control room manually by following these steps:
;)
1. Send colorbars from the same source (if possible) to all the monitors;
2. Kick each monitor into blue-only mode, which turns off the green and red guns;
3. Adjust the contrast, brightness, tint and color (saturation) so that all the bars look the same;
(You see, color bars are set up so that, when viewed on the blue gun only, adjusting the tint adjusts the brightness of two bars in opposite directions, the brightness another two bars, and so on. To adjust the contrast, you twiddle the contrast knob and look at the two associated bars -- one gets brighter, one gets dimmer. You set it such that the two bars appear to be the same brightness. Repeat for the other controls.)
4. Pop out of blue mode, and all the monitors look essentially the same. Piece of cake.
Of course, computer monitors don't come with a blue-only mode, and I believe even component monitors pull the sync signal off of green, so you couldn't just unplug the red and green.
So perhaps this advice isn't helpful. But if anyone out there is trying to calibrate TV monitors...well, glad I could help.