Monitor Calibration--Again

[rdenney]

Interesting. What video card is best for wide gamut monitors? The only reference to "bits" I am seeing on my video card specs is "64 bit memory interface".

I'm not sure any of them are really displaying only 8-bit color. I surely do often get smooth gradients. But if the monitor is really out of whack, and the profile is having to make big, big moves to get it back in whack, it could cause some posterization. I've seen it, but mostly I think it's more a scanner artifact (with a flatbed) than a monitor thing. The video card in my computer is not designed to be quick, but it is one of the better Radeon display adapters with native dual monitors and a separate LUT for each display. I am quite sure that is NOT my problem, at least for monitors that can be calibrated to be pretty close before profiling. But that calibration uses the same sensor that the profiler uses, and if the sensor can't see the display's gamut, it won't control the extremes. I don't think their software sets gray to be neutral, but rather looks at pure red, green, and blue, plus a sampling of other colors. If the pure red, for example, is significantly brighter than the sensor can see with only red light, it won't adjust the red enough and the result will be a reddish cast on the neutral colors. The profiler will try to correct the middle values, but it can't fix everything.

Rick "who didn't know the trouble being caused by buying a wide-gamut monitor, and who didn't even know it was a wide-gamut monitor when it was bought" Denney

[pherold]

To answer your question about 8-bit video cards I risk giving you more information than you want to know....!
There's been a movement afoot for a couple of years to try to get true 10-bit color from Photoshop to be actually viewable on a monitor. This requires a pipeline that has 10-bit support all the way from Photoshop to the operating system to the video card to the monitor. The monitor for example, would have to be one of the high end NEC's or Eizo's that support this. This article gives a lot of good information - like some of the common confusion about this - what OS's work - what video cards work...
http://www.imagescience.com.au/kb/qu...Output+Support

One of the reasons why NEC's and Eizo's are expensive is because they have their own high-bit graphics card built in to the display. This way these wide gamut monitors can have at least 1024 steps with which to define color (instead of 256). This helps, because the monitor can do the "heavy lifting" of adjusting the color and allow the computer's graphics card (which is almost always 8-bit) to not have to do much adjusting. This is why a Dell will tend to get some banding - especially if as Rick says, it has to make big moves which will limit the number of definable points to even less than 256.

[rdenney]

One of the reasons why NEC's and Eizo's are expensive is because they have their own high-bit graphics card built in to the display. This way these wide gamut monitors can have at least 1024 steps with which to define color (instead of 256). This helps, because the monitor can do the "heavy lifting" of adjusting the color and allow the computer's graphics card (which is almost always 8-bit) to not have to do much adjusting. This is why a Dell will tend to get some banding - especially if as Rick says, it has to make big moves which will limit the number of definable points to even less than 256.

So, you could say that the calibration step in software like iMatch is taking the place of all that LUT management inside those high-end monitors. We just achieve it by manipulating the brightness, contrast, and color controls on the monitor. I suppose the question would be whether those controls are software-driven and subject to their own limited data space, which I suspect some are. The objective of the exercise (whether done using the buttons or using a sophisticated monitor-base calibration system) is to minimize the color conversions that have to be made by the computer's video card software. We are working around a data-width bottleneck, same as we do when scanning.

And it's apparent, based on what you've provided, that my response to Kirk was related to whether 8 bits were being well used vs. whether they were being poorly used.

I don't think I can afford the 10-bit setup, even though I have some of the pieces in place. I guess when we target our images for web display, we ought to worry about it, though few on the viewer side will be able to see it anyway. When we target our images for printing, however, it seems to me that prints have less gamut than monitors, and that a bit of banding on the monitor is no issue if we know it won't be on the print.

Most of my output since upgrading to this monitor has been related to Blurb books and to making prints. I'm uploading scanned photos to my web page for the first time in a couple of years, after revamping my web page to make it easier to do, and now I'm running into all these issues.

Rick "appreciating the lessons" Denney

[Kirk Gittings]

Ok my info above was full of s__t.

I actually have an Eye One Display 2 and now I am confused about what I borrowed to check mine out. Anyway my ColorMunki Display came yesterday and I ran it a few minutes ago-truely dramatic difference from the profile created by the borrowed calibrator and clearly more neutral. That is hard to grasp unless you can look at the rendering of two profiles side by side. This program and hardware is simply more sophisticated and in sync with this generation of monitors and IMO well worth the $.

[rdenney]

Ok my info above was full of s__t.

I actually have an Eye One Display 2 and now I am confused about what I borrowed to check mine out. Anyway my ColorMunki Display came yesterday and I ran it a few minutes ago-truely dramatic difference from the profile created by the borrowed calibrator and clearly more neutral. That is hard to grasp unless you can look at the rendering of two profiles side by side. This program and hardware is simply more sophisticated and in sync with this generation of monitors and IMO well worth the $.

Okay, that confirms it for me. Time to whip out the plastic...

...again.

Rick "for whom this will be his third color management system" Denney