Card and Monitors and Color Space

This continues discussion in Buy & Sell on the CG220, a wonderful monitor.
Asher


FYI, Matrox Parhelia cards (which I have worked with for some years) show 10-bit colours by means of a PS plug in (the so called "10-bit GigaColor Plugin for PhotoShop").

FWIW .

Regards,

Cem

Can monitors take the 10 BIT and use it?

This may have hte potential if anything did!!

Asher

Asher Kelman said:

Can monitors take the 10 BIT and use it?

This may have hte potential if anything did!!

Asher

Click to expand...

A post that's worth repeating (from Karl Lang of Pressview and Artisan fame):

Here's an in-depth reply (from the Betterlight forum):


Greetings, fellow betterlight users. I lurk here and I try to keep my
mouth shut ;-) I can't spend too much time on this right now so
forgive me if I don't respond to questions quickly. For those of you
who don't know me I was the architect of the Sony Artisan, the Radius
PressView, ColorMatch, ProSense and many other products. I have worked
with display technology both CRT and LCD for the last 15 years.

Color accurate LCDs pose many problems. I will not argue the CRT vs LCD
debate. Suffice to say there are elements of a calibrated CRT that
still can't be matched by any LCD - available - and there are also
elements of LCD technology that exceed CRTs. We are improving things
at a rapid pace. I expect within 2-3 years to be able to finally feel
comfortable stating that we have an all around superior product in the
LCD space.

I am writing this email to attempt to dispel some myths and provide
some guidance for your LCD purchasing. You can't buy a good CRT any
more, the only ones left are of poor quality because the cost has been
reduced so much all the expensive quality components are not used
anymore. There was a reason that some CRTs cost 2-3K - the parts were
very expensive. Now the analog electronics use VLSI to reduce cost,
resulting in poor comparative quality.

1) A wide gamut LCD display is not a good thing for most (95%) of high
end users. The data that leaves your graphic card and travels over the
DVI cable is 8 bit per component. You can't change this. The OS, ICC
CMMs, the graphic card, the DVI spec, and Photoshop will all have to be
upgraded before this will change and that's going to take a while. What
does this mean to you? It means that when you send RGB data to a wide
gamut display the colorimetric distance between any two colors is much
larger. As an example, lets say you have two adjacent color patches one
is 230,240,200 and the patch next to it is 230,241,200. On a standard
LCD or CRT those two colors may be around .8 Delta E apart. On an Adobe
RGB display those colors might be 2 Delta E apart on an ECI RGB display
this could be as high as 4 delta E.

It's very nice to be able to display all kinds of saturated colors you
may never use in your photographs, however if the smallest visible
adjustment you can make to a skin tone is 4 delta E you will become
very frustrated very quickly.

2) More bits in the display does not fix this problem. 10 bit LUTs, 14
Bit 3D LUTs, 10 bit column drivers, time-domain bits, none of these
technologies will solve problem 1. Until the path from photoshop to the
pixel is at least 10 bits the whole way, I advise sticking to a display
with something close to ColorMatch or sRGB.

3) Unless the display has "TRUE 10 bit or greater 1D LUTs that are
8-10-10" user front panel controls for color temp, blacklevel and gamma
are useless for calibration and can in fact make things worse. An
8-10-8 3D LUT will not hurt things and can help achieve a fixed
contrast ratio which is a good thing.

Only Mitsubishi/NEC displays with "GammaComp" have 8-10-8 3D LUTs at
this time. Some Samsung displays may have this I don't test many of
their panels as the performance in other areas has been lacking.

Only the Eizo 210, 220 and NEC2180WG have 8-10-10 paths. If you really
want to know... the path in the Eizo is "8-14bit3D-8-10bit1D-10" go
figure that one out ;-) The 2180WG has an actual 10 bit DVI interface
with a 10-10-10 path but nothing supports it so you can't use it yet -
but for $6500 your ready when it does ;-)

4) The testing methodology for the seybold report article was very
poor. It demonstrates the authors complete lack of understanding with
regards to LCD calibration. At some point I may write a full rebuttal.
As an example the fact that Apple's display has no controls other than
backlight is actually a very good thing for an 8-8-8 LCD if your going
to use calibration. Apple optimizes the factory LUTs so as to provide
the most individual colors. smooth greyscale and the least loss. Then
the calibration is done in the graphic card LUT. As these are all 8 bit
it's best if the user does not mess with the display LUTs at all.
Overall Lab to Lab Delta E of 23 patches is a very poor metric to
evaluate a display. It completely leaves out many areas of color space
(the tool they used is designed to make the colorimeter look good so
tuff patches are not included) contrast ratio, stability, aging,
greyscale performance and other important considerations.

Many people ask for my recommendations. I am not happy with anything we
have right now. That said I can evaluate what there is.

Price performance wise the great bargain is the NEC 1980SXI BK the
price/vs colorimetric performance of this display can't be beat. The
2180ux Is a great display at a reasonable but high end price.

In the mid-high wide screen I like the Apple and the SONY. Reject the
display if uniformity is bad and make sure whomever you buy it from
will exchange it.

The Eizo 210 is great if you can justify the current cost. Give it two
years and most high-end displays should perform at this level. 220 is a
great display but suffers from all the downfalls of any wide gamut
display.

There is no reason to buy the La Cie 321 it's just an NEC with their
label on it and an extra $400.

The Monaco Optix XR is the best colorimeter for LCDs at this time.

These are my personal opinions.

Karl Lang

Well Andrew,

That's a fine piece of information! When was it written?

I think that having an aRGB gamut includes of more (of the printable colors) in what one can actually see! One can still make the adjustment on the CG 210 but look at the CG220 see those tones excluded in the CG210's monitor gamut to see what is happening. I'm not yet sure in my mind hoe beneficial that might be.

Asher

The same quote appeared last Christmas Day at LL. ~year is a long time in this biz....

http://luminous-landscape.com/forum/index.php?showtopic=9613

Scott,

That thread died out without adding more light to the debate.

Maybe an update by Karl lang, Bart or someone else might be helpful!

Asher

It was that thread and particularly this statement:

"Price performance wise the great bargain is the NEC 1980SXI BK the
price/vs colorimetric performance of this display can't be beat. The
2180ux Is a great display at a reasonable but high end price."

... that led me to look at the NEC displays. The xx80 series mentioned was replaced this year by the xx90 series. I looked at the market and concluded that, at about US$1k, the 2090uxi seemed to represent a pretty compelling "sweet spot" for someone looking for a serious 1600x1200 monitor without breaking the bank. I've had mine for about six months and could hardly be happier with it, and even moreso since I got the dedicated NEC Spectraview II software that calibrates the monitor directly via its internal 12-bit LUTs.

There's also the 19" 1280x1024 1990sxi and the 21" 1600x1200 2190uxi. And widescreen 24" and 26" versions — the 2490wuxi and 2690wuxi — are due to start shipping momentarily. The latter is spec'd to cover 92% of the Adobe RGB color space.

Nill
~~
www.toulme.net

Little has changed since Karl's first report with respect to more high bit support (nothing new in the OS, Photoshop, etc). Some new models yes, the OPTIX is being discontinued but nothing that solves the issues we have with display technology which no doubt is lagging way behind just about every other aspect of imaging hardware.

Hi Andrew,

You may have mentioned this previously, but in any case the question is worth repeating. Is there any practical benefit you see with the Gamut of the Adobe RGB monitors' larger space, (which of course anyway is insufficient), to work on say landscape or portraits or clothes photographed with say a Canon 5D and printed on a modern inkjet printer.

After all we are perceptually mapping anyway.

Is that perception better with ARGB so one might be able to more faithfully reproduce colors or create colors in phoroshop that can be seen and printed?

Asher

Having an extended gamut display is great (I have one) if you're working with extended gamut images. Where they fall apart, and to Karl's point is when you're NOT working on an extended gamut image. So if you have an image, say a bride in a white wedding dress that would fall completely into sRGB, you're spreading the bits too much in the display. What we need, and what I've yet to see is a display that can alter it's chromaticity for both and allow you to switch on the fly. The current wide gamut displays based on CCFL can't do this. I've seen one LED based LCD that supposedly can do this and that would be ideal. You use sRGB when the image dictates and Adobe RGB when such an image dictates and switch when necessary.

Thanks again Andrew for the helpful reply.

Do you have examples of scene types where sRGB is insufficient and Adobe RGB is helpful?

When you talk about "spreading the bits too much" are you referring to the accuracy of coordinates by which colors are accurately mapped in a 3D color space.

Or else do you mean the number of different colors defined (in a particular given image) in that space?

Asher

You can plot any rendered images color gamut in ColorThink. OR in ACR, toggle the Color Space options while viewing the Histogram and you can see if one falls outside gamut by clipping (in colors) on either end of the scale.

Great. That is useful!

Asher