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Author Topic: Maybe someone who is completely up to speed can elucidate  (Read 4943 times)

Lundberg02

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Maybe someone who is completely up to speed can elucidate
« on: September 02, 2014, 02:53:15 am »

In Mac OS 10.9.4 what does ColorSync do with embedded gamma, and what happens if the monitor is cal at 1.8? Similarly, what does the latest Safari do?
What do each of them do with an untagged image?
What is the situation with Windows and IE?
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pfigen

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Re: Maybe someone who is completely up to speed can elucidate
« Reply #1 on: September 02, 2014, 03:33:26 am »

Richard - If your file is untagged, both the Mac OS and Safari are going to assume the file is in Monitor RGB. If your file is tagged with an embedded profile, the OS will read that and use your monitor profile to display properly, no matter what the gamma - within reason. There's not much reason anymore (and hasn't been for a very long time) to use gamma 1.8 for monitor calibration. Unless you have a good reason for doing otherwise, 2.2 is the best all round choice. You're on your own with the PC.
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Lundberg02

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Re: Maybe someone who is completely up to speed can elucidate
« Reply #2 on: September 02, 2014, 08:13:55 pm »

I was pretty sure that was the case for Mavericks and Safari when the image was untagged now. I am not really sure what "display properly" means.  If the image is in ProPhoto the gamma is supposed to be 1.8. Before I got this new monitor, and before Mavericks, I got very good screen to print with the monitor at 1.8. When Mavericks came out, ColorSync was supposed to do magical things with gamma, but there was no explanation of what that means. Now that I have an aRGB screen , I am using the factory cal which is set for almost exactly 2.2, but I haven't tried any screen to print yet, because I want to have some idea of what is really going on if I convert RAW to ProPhoto, edit, and print from Photoshop manages colors to my six color Epson. I did this as an exercise before I got the new monitor, using one face from the ProPhoto test image and doing all four rendering intents just to see the differences. All I could tell from that was, yeah, they're different, and I actually liked the saturation better than the perceptual, which I suppose qualifies me as a weirdo if something else here in the forum hasn't already. I did that test using 10.9.2  and that version used sRGB as untagged default I believe.
 I'm trying to think whether I could use the black to white bars to figure what is happening to gamma if i use the ProPhoto test image or an Adobe 1998 test image. Maybe there's a better way to see the treatment of ProPhoto native gamma?
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pfigen

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Re: Maybe someone who is completely up to speed can elucidate
« Reply #3 on: September 02, 2014, 08:46:27 pm »

Richard - In the really olden days, back when people were concerned with printing to a first generation Laser Printer, and there was no color management, gamma 1.8 on a monitor was a closer match to the output than anything else, and it became the Mac standard that stuck around long after it was needed.

If every file has an embedded profile (sRGB, AdobeRGB, etc.) and you've got a good monitor profile, then any application that can use both profile will use those profiles to display your image properly. It does not matter if your working space is gamma 1.8 and your monitor is gamma 2.2, or the other way around. The profiles provide the conversion between the color spaces and it all happens without you ever having to lift a finger.

Gamma 2.2 for monitors has become more or less the norm because most uncalibrated screens were in the neighborhood of 2.2-2.4, and because for years, most screens were approximately sRGB, even untagged sRGB files would look pretty look on non color managed systems. Now, with more and more people, yourself included, using wide gamut screens, the importance of embedding profiles, calibrating screens, AND using color managed applications is more important than ever - if you're interested in seeing images how they were intended.

If you haven't gone out and picked up an i1Display Pro yet, you really should. I would not rely on factory settings or calibration for anything. You have no idea what that means or even what it is.

I think that you're really overthinking the whole process. Just get the calibrator, tag your images and forget about it. You really don't have to fret over this stuff anymore.
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MarkM

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Re: Maybe someone who is completely up to speed can elucidate
« Reply #4 on: September 02, 2014, 09:05:49 pm »

Richard - If your file is untagged, both the Mac OS and Safari are going to assume the file is in Monitor RGB.

I don't think this is true any more. Safari seems to assume untagged images (and HTML colors) are sRGB — at least in my tests.
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digitaldog

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Re: Maybe someone who is completely up to speed can elucidate
« Reply #5 on: September 02, 2014, 09:53:33 pm »

I don't think this is true any more. Safari seems to assume untagged images (and HTML colors) are sRGB — at least in my tests.
Mine too (10.9.5). Which is nice, about time.
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Lundberg02

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Re: Maybe someone who is completely up to speed can elucidate
« Reply #6 on: September 03, 2014, 02:08:48 am »

Peter, thank you for your cogent review of the history. Gamma 1.8 was used because boosted the mid tones the same way printers did to avoid flat looking prints, I believe. That is what I mean by asking, what does "properly" mean.  Properly for what and for whom? What actually happens to an embedded gamma correction?

I would have gotten an i1 Display Pro, but after steadily decreasing in price on Amazon from about 225 to 164 after rebate, it suddenly jumped back up to 234. Screw that. I don't know if they released a new version or what, I have seen nothing about it.

Andrew has 10.9.5 because it was just seeded. If it has returned to default sRGB this is about the fifth time they have switched sides. Why can't they make up their  (*&^&^%(IO* minds? i have 10.9.4, which was stated to be Monitor RGB.

Yes, I could stop fretting, but I'm an engineer and all engineers are OCD.
At night , I go to sleep muttering "color management is so f--- up no wonder no one does it right".
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pfigen

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Re: Maybe someone who is completely up to speed can elucidate
« Reply #7 on: September 03, 2014, 02:35:25 am »

Well, if Safari is now assuming sRGB for untagged files and web elements, it sounds good at first, but that's only going to create the opposite problem for anyone using a wide gamut monitor and happens to come across untagged files or elements. You really need to be able to specify how exactly you want untagged files treated, and that will change depending on what your screen is. That's not fixing the problem, only shifting it somewhere else.
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pfigen

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Re: Maybe someone who is completely up to speed can elucidate
« Reply #8 on: September 03, 2014, 02:51:00 am »

"Peter, thank you for your cogent review of the history. Gamma 1.8 was used because boosted the mid tones the same way printers did to avoid flat looking prints, I believe. That is what I mean by asking, what does "properly" mean.  Properly for what and for whom? What actually happens to an embedded gamma correction?"

I think you're still getting hung up on old technology and old terminology. Just ignore gamma 1.8 entirely. For your purposes, it does not come into the equation. It's the wrong thing to be focusing on. By "properly" I mean that you have a hardware calibrated monitor with it's own custom monitor profile combined with your working space profile, whatever that may be. To display properly, you always need at least two profiles - an source and a destination. For monitor viewing, the source is your working space RGB profile (or CMYK if you're in that space) and the destination is the monitor. Source = Working space. Destination = monitor. If you're going to print, then you add a third profile into the mix - your printer profile, and the monitor profile becomes in intermediate along the way to the printer. If you don't have a profile embedded, the application has to guess at what the source is, and that's where problems arise.

"I would have gotten an i1 Display Pro, but after steadily decreasing in price on Amazon from about 225 to 164 after rebate, it suddenly jumped back up to 234. Screw that. I don't know if they released a new version or what, I have seen nothing about it."

I just wouldn't worry about a few dollars. I think I paid about $225 at the time. The time you spend waiting for the absolute best deal is just not worth it for the amount of money you're talking about saving. Better to just get it and learn how to use it and then know that you're calibrated and not waste more time and money on bad prints

"Andrew has 10.9.5 because it was just seeded. If it has returned to default sRGB this is about the fifth time they have switched sides. Why can't they make up their  (*&^&^%(IO* minds? i have 10.9.4, which was stated to be Monitor RGB."

Sideways move and another bad decision by Apple.

"Yes, I could stop fretting, but I'm an engineer and all engineers are OCD.
At night , I go to sleep muttering "color management is so f--- up no wonder no one does it right".

Color management is not screwed up at all, but the implementation of it certainly is. I live this crap all day every day and there are more people who think they know what they're doing who have no clue than you could ever imagine. It's not really that hard to understand if you take it one step at at time. I'm going to push you one more time to just go ahead and get the X-Rite. Do it and you will just stop worrying about all these questions, or at least move you to a new set, which is moving forward.
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D Fosse

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Re: Maybe someone who is completely up to speed can elucidate
« Reply #9 on: September 03, 2014, 06:13:09 am »

Color management is not screwed up at all

Exactly what I've been saying for years. As long as you keep this little formula in the back of your head: source profile > destination profile, there's really nothing to it. That's the basic underlying mechanism that all color management operations, everywhere, rely on.

I think much of the confusion related to display is a failure to distinguish between calibration and profiling. Actually the calibration plays no part in color management - it just sets the environment. The profile OTOH is just a description of the display in its current state, whatever that is, calibrated or not.

As for browsers and untagged images - what needs to be done is to assign sRGB. Specifically. Not "assume", which really means "doing nothing". But assigning sRGB allows the color management chain to operate, and then it will display as intended even on wide gamut monitors.

Firefox has done this for a long time (mode 1), but it now appears that Safari (at least for Mac) has followed. I'm on Windows, so I can't test.
« Last Edit: September 03, 2014, 06:15:43 am by D Fosse »
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digitaldog

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Re: Maybe someone who is completely up to speed can elucidate
« Reply #10 on: September 03, 2014, 10:05:44 am »

Well, if Safari is now assuming sRGB for untagged files and web elements, it sounds good at first, but that's only going to create the opposite problem for anyone using a wide gamut monitor and happens to come across untagged files or elements.
Indeed but it's better than the old behavior of assuming your display profile. But you make a perfect point; if you want anyone to possibly see the previews correctly, you have to embed the profile that describes the numbers. Untagged files = bad.
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Lundberg02

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Re: Maybe someone who is completely up to speed can elucidate
« Reply #11 on: September 04, 2014, 06:38:40 pm »

pfigen is being gently didactic because we're old friends, even though we have never met. We used to attend the Apple, I mean Adobe, Seminars in Santa Monica in the last century, but didn't who was who.  Before I buy  an i1 for the equivalent of two months gas and electric to profile a wide gamut monitor whose factory cal on paper is better than I could ever do, and that I purchased brand new direct from Dell through a combination of fortuitous circumstances that could never be repeated by anyone, for half the price of the i1, I would like to know the following:
Does the i1 produce a  LUT profile with selectable rendering intents?
The Dell can have its LUT adjusted only by using the i1, does that whole process still allow selecting perceptual for the display rendering intent if the first question answer is yes?
I believe the i1 probably only does LUT profiles, so it should probably allow at least perceptual.
To respond to pfigen's  vowel movement and consonantal drift (his phrase), I naively trust the giant corporations and convert RAW from my Fuji to Pro Photo, edit, print using Photoshop manages colors using the correct Epson printer and paper settings with perceptual rendering intent. Six color printer, matte Epson paper, OS 10.9.4, CS 5.5.  This has produced prints that seem to match my old  Dell sRGB screen good enough for me. I haven't gone through the exercise with the wide gamut yet because I want to better understand what I'm actually doing since Apple gratuitously decided that ColorSync is omnipotent.

I am going to make a bold statement:  Adobe soft proofing doesn't really soft proof because you don't know the display rendering intent and couldn't change it anyway.
I have never used soft proof, because it's easier for me just to print.  So I speak as an idiot, just like television.

 Another question: Does Photoshop CC use v4 LUT profiles for its working spaces now, so that rendering intents can actually be used when converting, and might actually be seen on a wide gamut monitor?
« Last Edit: September 05, 2014, 12:00:33 am by Lundberg02 »
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digitaldog

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Re: Maybe someone who is completely up to speed can elucidate
« Reply #12 on: September 04, 2014, 07:12:20 pm »

Another question: Does Photoshop CC use v4 LUT profiles for its working spaces now, so that rendering intents can actually be used when converting, and might actually be seen on a wide gamut monitor?
It can if you have such profiles. None are installed by Adobe. And sRGB is the only V4 working space profile I'm familiar with and further, if it doesn't fully follow the V4 spec (support what is called the PRMG), it's a V4 profile in sheeps clothing. You can get additional rendering intents but not the full functionality that V4 promised.
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pfigen

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Re: Maybe someone who is completely up to speed can elucidate
« Reply #13 on: September 04, 2014, 07:38:48 pm »

Richard,

You wouldn't really want Perceptual for your display profile. You really want to see the colors that your screen can show you to be shown as accurately as possible. At least that's my way of looking at it. Perceptual tables can change for the color rendition and the luminance of in gamut colors as they get squished together, and for my money, I want it Relative.

Soft proofing does work just fine as you have all the available rendering intents available in your printer profile. When you're printing, the monitor is only an intermediate destination for the file that is on its way to the printer - the final destination. You do have, in that case, Perceptual, Relative, Absolute and Saturation all there for those conversions - from working space to output space.

Stop comparing the price of an i1 to your utilities or anything else. That makes no sense at all. And even IF you screen came well calibrated from the factory, which I highly doubt, you're going to want to recalibrate it every month or so anyway. Whatever price you pay is a bargain. You're an engineer, you should know that already.
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Lundberg02

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Re: Maybe someone who is completely up to speed can elucidate
« Reply #14 on: September 05, 2014, 12:13:25 am »

What I should have said and was in too much of a hurry, was that an sRGB monitor can't really soft proof because the display gamut is smaller than a lot of printers or at least doesn't contain some printer colors in the case of ink jets. I'm not sure what the display's rendering intent does either. I have read that monitors use perceptual. I think that would depend on the manufacturer and/or the display profiler app.
I think that an aRGB monitor would provide a much better, but still not totally accurate soft proof, but what do I care, I'll never use it un;ess I decide to check a print after the fact.
I go from RAW to ProPhoto to manages colors to perceptual for my prints, so when I do it now with a wide gamut display I'll get more colors in gamut and be pretty, oh so pretty, lala la lala la la.

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pfigen

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Re: Maybe someone who is completely up to speed can elucidate
« Reply #15 on: September 05, 2014, 01:08:59 am »

"What I should have said and was in too much of a hurry, was that an sRGB monitor can't really soft proof because the display gamut is smaller than a lot of printers or at least doesn't contain some printer colors in the case of ink jets."

On the surface, that sounds well and good but in practice, soft proofing works very very well with an sRGB-ish display. It really does. I've made thousands of print over the last decade on large formate Epson's and soft proofed them all on a lowly Sony Artisan. Every once in a while there'd be a surprise, but not where you expect. I specifically remember printing an image for Honeywell that had factory workers in standard issue blue smocks. The files (sRGB btw) looked perfect on the Artisan, but the first print, printed through my own custom paper profile, rendered those blue smocks way too saturated. sRGB file. sRGB monitor, and an Epson 9900 printer using Lexjet eSatin, which is the equivalent of Epson Premium Luster. Now that was a surprise. I dropped the saturation of the blues and reprinted. Perfect. But, by and large with many thousands of images, they just printed right and we moved on to the next. Not a big deal.

Now, with a new Eizo CG277, which has ninety-nine percent of Adobe RGB, the results are basically the same. Yes, there are some brighter colors on the Eizo but for most images, it just doesn't matter, and when it does matter it's never as huge a deal as so many here would have you believe.

"I'm not sure what the display's rendering intent does either. I have read that monitors use perceptual. I think that would depend on the manufacturer and/or the display profiler app."

No, the monitors, as far as I know all use Relative to go from working RGB to the monitor profile. As I said earlier, it wouldn't make any sense to use anything else. It's not "up" to the monitor manufacturer. It's up to the color management system, and the imaging application you are using. A display doesn't have a rendering intent itself, only the system of profiles  - Source and Destination - that are in place to display your images.

And to  further emphasize this, you need to go no further than the advanced panel in the Color Settings dialog and look to the "Desaturate By ___ Percent" option for you display. That option, which virtually no one ever uses and even fewer actually know about, was put there to simulate the effect of a Perceptual rendering intent on you monitor. And it does indeed work. Take a saturated ProPhoto RGB file with super saturated color with detail (you can measure the detail you can't see using the Info Palette - if the numbers move around as you move the cursor, you know there's color differentiation even when it's invisible on screen), then put in a number - say thirty percent or so, and magically, you'll be able to see the gradations in you file that were once completely hidden. Of course, the overall color accuracy will be compromised. It's a cool feature but it's not very practical on a day to day basis. But now you know about it.

"I think that an aRGB monitor would provide a much better, but still not totally accurate soft proof, but what do I care, I'll never use it un;ess I decide to check a print after the fact."

Yes, in theory you're right, the wider gamut monitor will be more accurate, but only in the areas and in images that actually have larger than sRGB color data.

"I go from RAW to ProPhoto to manages colors to perceptual for my prints, so when I do it now with a wide gamut display I'll get more colors in gamut and be pretty, oh so pretty, lala la lala la la."

Well, maybe. It all depends on your exact workflow and how you handle your files. It's all too easy to push your files too far in ProPhoto, particularly if you aren't paying close attention to the numbers as you manipulate your image. Perceptual rendering is always a compromise and it's not always the best compromise. If you're using a wider-ish gamut inkjet paper with a gloss or semi-gloss paper, you might actually like Relative Colorimetric rendering, especially when you're dealing with most "ordinary" images - those without super saturated flowers and the like.
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Lundberg02

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Re: Maybe someone who is completely up to speed can elucidate
« Reply #16 on: September 05, 2014, 01:53:01 am »

I have looked at the Desaturate By, but never needed to try it. That's a good hint. I know that you are the best sRGB worker I've ever seen so your experience with soft proofing is gospel as far as I'm concerned.
BTW the damn i1 just went up another twenty bucks or so. What in the  h e hockey sticks is going on?
Are the terrorists buying them to scare us?

One more thing. And this is wack.
I just went to ColorSync Utility to inspect all the profiles I use under System , Display, User, Other, Printer, and the Inspector says every one of them is Perceptual.  Not a single Colorimetric in the bunch. OS 10.9.4.  Color management is not screwed up? It is to laugh.
« Last Edit: September 05, 2014, 02:12:40 am by Lundberg02 »
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pfigen

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Re: Maybe someone who is completely up to speed can elucidate
« Reply #17 on: September 05, 2014, 02:24:12 am »

Don't believe everything you read. Often the default rendering intent is set to Perceptual in profiles but that does not mean that's what is happening in actual use. The ColorSync Utility reports working space profiles as being Perceptual as default and those don't even have perceptual tables. Means nothing. 

The old X-Rite DTP-92, which I still have laying around was $600 back in the day. $245 is still a bargain. Price the Discus from BasicColor and you'll buy it before the price goes up even more.
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digitaldog

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Re: Maybe someone who is completely up to speed can elucidate
« Reply #18 on: September 05, 2014, 11:12:09 am »

What I should have said and was in too much of a hurry, was that an sRGB monitor can't really soft proof because the display gamut is smaller than a lot of printers or at least doesn't contain some printer colors in the case of ink jets.
Maybe not a great analogy but that's like someone needing a 100 watt bulb for a lamp, only finding 60 watt bulbs and deciding they will just sit in the dark.
Even with a wide gamut display, there are colors outside it's gamut that does fit in gamut of the output device. And the point is, there are lots of colors that can be seen. And there's far more to soft proofing than just seeing all the saturated colors that can be output! Anyone that tells you that soft proofing is 100%, is confused or lying. But a 95% match is better than a 80% match and soft proofing is about using the tools we have to better predict the final output. So this idea that soft proofing isn't effective because you're stuck with an sRGB-like display is throwing out the baby with the bath water.

IF you can make lots of prints without regard to the display, either with or without a soft proof, you could be working on a grayscale display. You don't need a lick of color management. Suggesting that soft proofing isn't effective because of the display gamut (and there are colors the display can emit you can't print FWIW) is like suggesting you don't need a color display, let alone one that is sRGB-like and calibrated. Just print, alter the numbers in the document, print again until you get what you want. It's time consuming and expensive but works if you are using OPM (Other People's Media) and get paid by the hour.
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digitaldog

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Re: Maybe someone who is completely up to speed can elucidate
« Reply #19 on: September 05, 2014, 11:13:06 am »

I have looked at the Desaturate By, but never needed to try it.
It's a kludge and should never have been placed in the color settings in the first place.
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