wide gamut monitors

[DanK]

[Edited to reflect information in an earlier thread.]

I apologize if this has been asked and answered. I searched for old threads but didn't find one that was exactly on target. This one (Clarification on Color Management (Working Spaces and Rendering Intents)) comes close.

Dell now sells 4K monitors that cover nearly all of the Adobe RGB color space. I'd like the finer resolution, but it's not clear to me how much the wider gamut would help.

To the extent that the gamut produced by my printer includes colors that are in Adobe RGB but not in sRGB, it seems to me that I can do better editing/soft proofing for my printer with an Adobe-RGB-gamut monitor. However, most people are viewing photos with sRGB monitors, so it seems to me that one would have to switch the display to sRGB at some point in editing to be confident of how the images would look to them.

So, if I am right, if one is concerned with accurately predicting what an image looks like on screen, an issue with Adobe RGB monitors would be how easy it is to switch to an sRGB color space when editing. I wouldn't want to work in the sRGB space in general, to avoid losing information. Do those of you with Adobe RGB-capable monitors find that you need to do this, and if so, how do you do it?

Many thanks

Dan

[ajohnw]

That's how I see it too Dan with the rider that if some one want to adjust to the best of their abilities and wants others to see what they saw the web has to be sRGB. That makes prints and soft proofing entirely separate. Some people do this already via aRGB monitors. They soft proof in that and jpg's in sRGB mode. Some also view images in 10bit aRGB but currently that's all they can do - view them maybe along with max resolution problems due to available band widths on pc to screen links at the moment.

Where you may run into some grief going to a higher resolution is text sizes in places around in a PC. I've been there in the past where higher resolutions than the OS was intended for are available. Some font sizes can be adjusted to suit and I found that some couldn't be. Actually I feel a bit like that on my 30in 2560x1440 Dell in places. I think the dot pitch is close to 100 dpi, can i see them from normal viewing distance - no. I feel 4k is really for much larger screens where currently on TV's for instance I understand some use interpolation ftom HD and get away with it because it can't be seen at usual viewing distances where as none HD interpolated to HD is clearly visible even on a 40in TV from a couple of m.

Looking at their 32in 4K Dell for instance the dpi comes out at close to 140. That will make text rather a lot smaller than my current monitor. the $2500 price tag might put me of too by the time it gets to £'s. If they did say a 40in the dot pitch would be greater and maybe match my 100 so text size and image size and everything else would be the same and I would have more real usable real estate. I feel this sort of thing is worth thinking about before making a change. On that score you might like to read this on an other 4K monitor. Just the beginning and conclusions really. I'd also note it's a true 8bit panel unlike some of Dell's more recent sRGB ones. Maybe they will do an aRGB version at some point. Also notice comments about refresh rates and cards noting Dell's drop to 30Hz on HDMi - I assume because their HDMI interface is out of date but there does seem to be some problems in that area at the moment.

http://www.tftcentral.co.uk/reviews/..._bdm4065uc.htm

John
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[DanK]

John,

thanks. I had not thought about font sizes on 4K monitor.

I would be limited to 24" or at most 27" by space constraints. Those are far less expensive.

Dan

[xpatUSA]

[Edited to reflect information in an earlier thread.]

Dell now sells 4K monitors that cover nearly all of the Adobe RGB color space. I'd like the finer resolution, but it's not clear to me how much the wider gamut would help.

To the extent that the gamut produced by my printer includes colors that are in Adobe RGB but not in sRGB, it seems to me that I can do better editing/soft proofing for my printer with an Adobe-RGB-gamut monitor. However, most people are viewing photos with sRGB monitors, so it seems to me that one would have to switch the display to sRGB at some point in editing to be confident of how the images would look to them.

So, if I am right, if one is concerned with accurately predicting what an image looks like on screen, an issue with Adobe RGB monitors would be how easy it is to switch to an sRGB color space when editing. I wouldn't want to work in the sRGB space in general, to avoid losing information. Do those of you with Adobe RGB-capable monitors find that you need to do this, and if so, how do you do it?

Many thanks

Dan

I don't have a wide-gamut monitor, Dan, but was looking at some very wide-gamut monitors a few days ago, prompted by the recent "Pointer's Gamut" thread. Since I only view my images on my monitor and I don't print, I though it might be nice to have a 4K monitor that complies with Rec. 2020 (much wider than Adobe RGB (1998)). Now, if the Dell 4K monitors cover "nearly all" Adobe RGB (1998) that tells me that they are only a bit better than Rec. 709 (HD TV) which is more or less sRGB, see here. I'm thinking that their native primaries are different than sRGB which means a native gamut wider than sRGB but not completely encompassing Adobe RGB (1998) (prob the easy-to-do green primary). If I were in your position, I'd be looking for a monitor that encompasses all of Adobe RGB (1998), not "nearly".

I too am stumped by the practicalities, but a Rec. 2020-compliant monitor would be my choice. 'mongst other things Rec.2020 specifies 10-bit or 12-bit color. No more ditherin'

For sure, images for printing would need different profiles from web output, as already true. But now 3 profiles might be needed for me . . another for the Rec.2020 primaries which are far beyond Adobe RGB (1998) but not as far as ProPhoto.

[ajohnw]

I feel that other than maybe buying an aRGB monitor with the normal resolution limits it would be better to wait for the dust to settle which is likely to take a long time. TV panels eventually find their way into monitors and just maybe gamuts will be standardised at some point.

aRGB is only needed by people who print. Not that I have any strong opinions. It's whole purpose in life is to get round the limited dynamic range in that media while just stopping short of banding. 10bit aRGB removes that but go find a 10bit printer. It doesn't help with so called prophoto printers that can't really print that full gamut as people finish up trying to correct colours they can't see. The problem with printing is that it has something like a 6 stop dynamic range against a monitors circa 9. The fix for this is supposed to be to use more saturated colours to make up for lack of contrast from dynamic range. I have seen an argument on the web that applying gamma to monitors decreases it dynamic range for 8 stops to 7. Missing the point that gamma is intended to correct the relationship between the numbers and the amount if light the display emits as a result. In other words some number that represents mid grey wouldn't show mid grey without it.

Out of interest some astute people bought TV's rather than monitors when HD arrived because bigger ones were cheaper. Might be the same with 4K but not yet I would have thought. To be honest if the Phillips one had been around when I bought this Dell I would have gone for it. I have space for a larger monitor but not 2.

John
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PS a 9 stop dynamic range implies a dynamic range of 512:1 my monitor has a measured dynamic range of 894:1. If I ran at 150 cd/m^2 it would probably be higher. I run it at 103.

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[Manfred M]

Let's differentiate between what 4k gives you and what wide gamut gives you; especially from a photographer who does PP viewpoint...

Good colour reproduction is very important to getting a top-notch colour corrected image. I work with a dual screen setup; with my main screen being a wide gamut one (most of Adobe RGB) and my second one is 100% sRGB compliant. Both screens are calibrated and profiled and run off the same video card.

Yes, there is definitely a difference between the output of the two screens and the colours are a lot more vivid (when those colours are in the image of course) when I edit in a wide gamut colour space (Adobe RBG or ProPhoto). The is little difference between the two when I work in sRGB, although my sRGB screen does have a touch of a bluer colour cast than my main screen. I print a fair bit and do use a wide gamut colour space; there is defintely a difference in colour depth on my Epson 3880 when I use ProPhoto or AdobeRGB rather than sRGB. My default working colour space is ProPhoto.

I remember when Apple first came out with their Eyefinity displays; they had great resolution and poor colour reproduction (this was fixed in later models). Same issue here - high gamut versus 4k resolution.

The arguments regarding dithering is an interesting one, as the various computer screen manufacturers do not share their data on this technology, so it's anybodies guess as to what the technology really does. I firmly am on middle ground here; convinced that you do get better colour performance out of these displays (8-bit + 2 bit via dithering) than without it, but would love to see a true native 10-bit display. None exists so far as I know, and if they do, these would be far outside of any price range I would be willing to pay for one.

Bottom line; for photo editing, I would definitely go for a high gamut screen rather than a 4k one. for photographic work. I would never use an sRGB screen if I had a high gamut option available to me.


Now if I were concentrating on editing 4k video, I would go the other way. Getting a native resolution screen is the only way to do video, in my experience. Any non-standard modes tend to give misleading artifacts when working video.

[Manfred M]

Not that I have any strong opinions.

John - I think someone has hijacked your user ID!

[Simon Garrett]

There are certainly problems with high-res monitors on smaller screens in Windows; at higher resolution the default text size can be too small to read comfortably. You can alter the default text size (from the screen resolution page in Control Panel) but it's not wholly effective and not all applications take note of that setting, so you can end up fiddling with text size all the time. Been there, done that, didn't like the T shirt. Personally I would not go beyond 1920 x 1200 in 24 inches. But 4K is great in larger (= more expensive) screen sizes - 31 inches or preferably more.

Another issue: many graphics cards won't go to 4K resolution, so you might need a new graphics card.

As to wide gamut: I like having wide-gamut displays, but it's useful to be able to switch to sRGB to see how things will look on the web. On many modern wide-gamut monitors you can switch with a single click (which changes the colour space of the monitor and usually changes the Windows profile, so software knows to use a different profile - although some software requires a restart to recognise a change of profile).

Also, unmanaged software looks too saturated on a wide-gamut monitor (e.g. the Windows desktop). Some browsers don't do colour-management properly, and don't look good on wide-gamut; in fact, Firefox is the only fully colour-managed browser, with Safari a close second. Chrome is not properly colour managed (it was, but an update earlier this year broke it, and I don't think it's fixed), and Internet Explorer (even the latest) is a complete waste of space for colour management (contrary to what Microsoft wrongly claims, and some so-called browser test pages suggest - IE does only half the job of colour management and is useless for wide-gamut monitors).

PS - aRGB is not the same as Adobe RGB; "aRGB" or "ARGB" have various meanings quite different from Adobe RGB. You'll get some very strange looks from people that know what ARGB really means.

[xpatUSA]

. . . , but would love to see a true native 10-bit display. None exists so far as I know, and if they do, these would be far outside of any price range I would be willing to pay for one.

How about $599 at B&H, Manfred?

HP DreamColor LP2480zx Professional LED Backlit 24" IPS LCD Monitor

Rec.2020 gamut and 10-bit if that Pointer's Gamut link is to be believed. There's at least one other.

bits description is a bit weaselly though "Minimum 10 bits/color throughout video processing pipeline" . . hmmm . . .

[Manfred M]

bits description is a bit weaselly though "Minimum 10 bits/color throughout video processing pipeline" . . hmmm . . .
[/SIZE]

Sounds really weasly to me. If it were truely 10-bit they would be shouting that fact off the roof-tops, rather than using language like that. I would be very surprised if it were anything other than 8+2. From a price point, it fits into the other 24" 8+2 IPS displays.

[Simon Garrett]

HP DreamColor LP2480zx Professional LED Backlit 24" IPS LCD Monitor

Trusted Reviews liked it (http://www.trustedreviews.com/HP-Dre...Display-review) but it's not very new - I found a reference that it was launched in June 2008 (http://www.tftcentral.co.uk/news_arc....htm#hp_lp2480).

[ajohnw]

It's better to look at tftcentrals actual reviews on monitors. They dismantle them to see what panel is actually fitted. I'll leave you to guess why they do this. Some interesting things emerge such as Dell were producing good 8 bit panel sRGB monitors, now they seem to be offering 6+2. There hardware calibrated just like the bulk of aRGB monitors are 8+2. Of late they have mentioned that dithering can be seen but as I have a phobia about that I might be reading something into their comments.

There are true 10bit channel monitors about. The only ones I have found are mainly intended for video work, small and rather expensive. There is also the

Eizo ColorEdge CG223W - 22" 10-bit VA Panel. There may be a few others. There may be more at reasonable prices when and if TV's go 10 bit. I wouldn't accept that the Eizo is really 10bit unless the actual panel type was available.

Some argue that 10bit is needed to ensure coverage of all of the sRGB space. Well have a look at mine - 30in was wishful thinking I have the 27in I wish it was bigger.

http://www.tftcentral.co.uk/reviews/dell_u2713hm.htm

It fully covers sRGB, in fact over covers it. My previous ViewSonic monitor just lacked a tiny bit of blue. All down to LED back lighting. The 40in phillips monitor is so close to covering it that measurement errors would be significant. It isn't an easy thing to measure.

( A clue as to why they dismantle and take a look - claims like 30 bit have been miss represented before in the past. )

John
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[davidedric]

A few months ago I bought a Samsung Tab S tablet. It has a pretty amazing screen. Here is a review with the measured gamut:

http://www.displaymate.com/Gamut_20.html

Doesn't do me much good with photos since I always export from Lightroom in sRGB, and it's not colour managed,but some of the supplied sample images look spectacular.

Dave

[ajohnw]

Make a nice change to see another review site that actually measures it. May a well just read the manufacturers blurb rather than bother with most of the rest.

It looks short of aRGB to me though. This gives some idea of what that looks like against sRGB



If I had selected perceptual the missing colours in aRGB would look worse. Interesting what. (Using a Victorian expression.) Changing the colour space format used alters the relationship as well but I have used the same format as the tablet link. The other formats make the difference look smaller. I wonder which one people who are reading this would use if they wanted to argue aRGB is better? When this is changed the visual gamut size/shape alters as well.

John
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[xpatUSA]

<>

PS - aRGB is not the same as Adobe RGB; "aRGB" or "ARGB" have various meanings quite different from Adobe RGB. You'll get some very strange looks from people that know what ARGB really means.

Thanks for the reminder, Simon - I was getting lazy . .

And we should all note that "Adobe RGB" by itself does not specify a particular Adobe gamut, there being two that I know of: "(1998)" and "Wide Gamut".

For anyone deeply interested in color, there's a nice calculator on Bruce Lindbloom's site here:

http://www.brucelindbloom.com/

Click on the Calc button, then select "CIE Color Calculator". Since we're posting several type of gamut diagrams here, it can convert coordinates from one CIE color model to another, set white balance parameters, and quite a bit more.

[ajohnw]

It crops up so often I am fed up with typing the name adobe so will stick to aRGB as it's pretty obvious that it doesn't relate to an alpha channel in the context that it is used.

John
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[ajohnw]

This always makes me smile.

Historical background[edit]
Beginning in 1997, Adobe Systems was looking into creating ICC profiles that its consumers could use in conjunction with Photoshop's new color management features. Since not many applications at the time had any ICC color management, most operating systems did not ship with them.

Lead developer of Photoshop, Thomas Knoll, along with his brother John, decided to build an ICC profile around specifications he found in the documentation for the SMPTE 240M standard, the precursor to Rec. 709. SMPTE 240M's gamut was wider than that of the sRGB color space, but not by much. However, with the release of Photoshop 5.0 nearing close, Adobe made the executive decision to include the profile within the software.

Although users loved the wider range of reproducible colors, those familiar with the SMPTE 240M specifications contacted Adobe, informing the company that it had copied the values that described idealized primaries, not actual standard ones. The real values were much closer to sRGB's, which avid Photoshop consumers did not enjoy as a working environment. To make matters worse, Knoll had made an error when copying the red primary chromaticity coordinates, resulting in an even more inaccurate representation of the SMPTE standard.

Adobe tried numerous tactics to correct the profile, such as correcting the red primary and changing the white point to match that of the CIE Standard Illuminant D50, yet all of the adjustments made CMYK conversion worse than before. In the end, Adobe decided to keep the "incorrect" profile, but changed the name to Adobe RGB (1998) in order to avoid a trademark search or infringement.[1]

Some companies would edit it out.

John
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[Simon Garrett]

I agree with you both about aRGB - in photographic circles it's often used instead of Adobe RGB, and even if it's not correct, everyone knows what you mean. I'm just being pedantic

Happy New Year everyone!

[xpatUSA]

Dan, if you haven't read this yet, it explains the pros and cons very well, IMHO.

http://www.xbitlabs.com/articles/mon...0_2.html#sect0
.

[xpatUSA]

Sounds really weasly to me. If it were truely 10-bit they would be shouting that fact off the roof-tops, rather than using language like that. I would be very surprised if it were anything other than 8+2. From a price point, it fits into the other 24" 8+2 IPS displays.

Found this snippet at the TFT Central site:

In fact, modern RGB LED displays such as the HP DreamColor LP2480zx even use a one-of-a-kind true 10-bit H-IPS panel (not 8-bit +AFRC like some of the other modern "10-bit" screens)

http://www.tftcentral.co.uk/articles...cklighting.htm

As our Bill might have said "it all depends on what the meaning of 'such as' is . ."