AdobeRGB & ISO profiles incompatibility?

Discussion in 'Digital Darkroom' started by jonathan_mcgraw, Apr 28, 2019.

  1. There is a tool in Photoshop, "View/Gamut Warning" you can click to highlight any parts of the image out of gamut in the current color space. I can't find any examples in my photos rendered under AdobeRGB and sRGB. I suspect you have to go out of your way to create them.
     
  2. digitaldog

    digitaldog Andrew Rodney

    Yes and it doesn't matter. They key is sending the best quality 8-bits per color to the drivers and OS.
    On the Mac, on a few Epson's, the driver passes full "16-bit" to the driver. There are other ways to do this too (Canon Plug-in, 3rd party drivers). I've never seen any difference nor measured any difference sending either and comparing. High bit data is about editing overhead. So the drivers really don't need more data.... Today.
     
  3. Jonathan,

    “The responses above include a lot of what you need to know, but given that you are new to this, I will wager that you find this discussion more confusing than helpful. So, let me try to pare things down, at the risk of repeating in a different form a few things already mentioned.”

    Hi there paddler4

    I realized when I read the above posts, that I got ISO & ICC confused. I have tried to res;pond to many of the above posts, but I can only get this one to reply to.

    Thank you, for your points below, Jonathan

    “1. If you want to preserve as much color detail and editing flexibility as possible, shoot in raw. That will give you a wider gamut (a wider range of colors) than either Adobe RGB or sRGB.”

    I shoot nikon RAW aRGB-Jon

    “2. Good printers (and in terms of gamut, the Pro 100 is a very good printer) can print colors that are outside of the sRBG gamut and some that are outside of Adobe RGB.”

    Sounds good-Jon

    “3. If you take JPEGs, then the colors outside of whichever gamut you pick are simply gone. If you shoot raw, it makes absolutely no difference whether you set the camera to Adobe RGB or sRGB.The data outside those gamuts is still present, and Lightroom will ignore the setting you choose.”
    I'm going to have to Google this. It doesn't make sense. (Although when I was a adolescent & teenager learning photography I was sometimes able to learn something as just a fact w/o understanding the why, but I've usually done better when I understand something on a conceptual level)-Jon

    4. Lightroom's internal working color space is "Melissa," a variant of the Prophoto color space, which is larger than the other two. Unfortunately, if you shoot JPEG, this doesn't help you much, other than giving you a little more flexibility in editing. If you shoot raw, it preserves more of the color data.
    So "Melissa," has a larger color gamut than aRGB or sRGB. No? -Jon

    “5. If you want your display to look similar to the final print, you have to calibrate the monitor.” OK-Jon

    6. The gamut produced by the printer is a function not only of the printer, but also of the paper you use. That's what you need ICC profiles for. All of the major paper vendors I have used provide ICC profiles for the Pro 100. they also provide instructions about the paper setting you should use.” This makes sense-Jon

    7. LR allows you to soft proof, that is, to see approximately what a print will look like with that printer and a given paper, if you have loaded the ICC into Windows. I don't think it is terribly accurate, but it can help. - Soft proof I've wonder what that meant. Not terribly accurate. OK -Jon

    8. If you are printing in color from Lightroom, you have to tell the software that it should control color, not the printer. This requires two steps with your printer. First, in the lightroom print module, down at the lower right, you will see "color Management." The first entry in that box is "profile". Change this from "managed by printer" top the profile for your paper. (Note: when you load the ICC into windows, it will show up here, but you have to check a tick box to tell LR to consider this an active profile.)-OK-Jon Then, when you to to the page setup (left bottom) or print (right bottom) dialog, go to properties. This is where you set the paper type, the paper size, etc. Go to the second tab and you will find a section labeled "color matching". Set this to "none." This tells the printers firmware that it is not supposed to manage color.
    -I think I will be able to do this, although so often w/ software it doesn't show up on my screen the same as in an example-Jon

    It's worth the time getting familiar with all of this. That printer is capable of stunning results. Since it uses dye-based inks, the prints aren't archival, but they are very good. I have printed quite a bit with one of them, and the results are very hard to distinguish from the prints I produce with a $1300 printer.

    Paddler, I've learned more about Digital processing from this post that I have from all my past futile studying. Thank you so much
     
  4. Thank you, Joe “…..about the colour space if it causes printing issues.” How would this type issue manifest it's self ?[/QUOTE]
     
  5. Nick Thank you, I've printed this out-Jonathan
     
  6. OK Ed. I'm making notes from this thread. This has been added-Jon
     
  7. Yes, that is correct.

    The key to this is that the camera setting you use--sRGB or Adobe RGB--simply has no effect on the raw file at all. The setting is there only for shooting JPEG. Think of it as a number line. Say, just for illustration, that the raw file read into Lightroom contains colors 1-100 in the big color space Melissa. If you convert that to Adobe RGB, you might loose 30 of those 100 colors. if you convert to sRGB, you might lose another 20. (These are just for illustration--I haven't looked up the actual size of these three color spaces.

    If you edit in Lightroom and print directly from Lightroom, you never have to convert to JPEG at all, which means that you don't need to convert to the smaller color space. You will lose some colors that the printer can't manage--which will show up as "out of gamut" when you soft proof in Lightroom.

    On the other hand, if you want to post online, then you do need to convert to JPEG, and you need to pick one of the smaller color spaces. Since the large majority of computer monitors are at best sRGB-compliant, most of us produce sRGB JPEGs to post online.
     
  8. What happened to Ed's post? I need to find how to correctly reply to a post in this forum. Another thing to study/ learn :-\
    So "Melissa," has a larger color gamut than aRGB or sRGB. No?

    Yes, that is correct.

    “The key to this is that the camera setting you use--sRGB or Adobe RGB--simply has no effect on the raw file at all. The setting is there only for shooting JPEG. Think of it as a number line. Say, just for illustration, that the raw file read into Lightroom contains colors 1-100 in the big color space Melissa. If you convert that to Adobe RGB, you might loose 30 of those 100 colors. if you convert to sRGB, you might lose another 20. (These are just for illustration--I haven't looked up the actual size of these three color spaces.”

    -I understand that the numbers you listed are an example only. So is it fair to say that Nikons' listing of 2 RAW types is marketing dept hype?-Jon

    “if you edit in Lightroom and print directly from Lightroom, you never have to convert to JPEG at all, which means that you don't need to convert to the smaller color space. You will lose some colors that the printer can't manage--which will show up as "out of gamut" when you soft proof in Lightroom.”

    -I've suspected for quite some time, that JPEG is similar to reversal film & RAW is comparable to negative printing only much more versatile than the wet darkroom-Jon

    “On the other hand, if you want to post online, then you do need to convert to JPEG, and you need to pick one of the smaller color spaces. Since the large majority of computer monitors are at best sRGB-compliant, most of us produce sRGB JPEGs to post online.'

    -OK, I've wondered about this. I understand now-Jon


     
  9. Paddler4, I want to thank you for giving the OP such a good answer. I want to add something tho for anyone (like me) who uses a Mac with OS X. When you choose a printer profile from Lightroom, the Mac printer driver automatically turns off color management in the printer. If you open the "Color Matching" part of the print dialog, you will see this:
    nochoice.jpg
    Notice that the two choices are greyed out, but "ColorSync" is selected. ColorSync tells the printer to use the profile, not the printers own management.

    If you choose "let printer manage" in Lightroom, you see this:
    choice.jpg
    Notice that the selected button is "Canon Color Matching".

    If you choose "Color Sync" in this case, you are then given a drop-down list of profiles to choose from - the same list that you could have chosen in Lightroom.

    I hope this helps Mac users: I have not found this documented online before.
     
  10. digitaldog

    digitaldog Andrew Rodney

    That 'tool' is nearly worthless for so many reasons: Buggy, inaccurate and predates soft proofing and the use of ICC profiles to convert and handle Out of Gamut (OOG) colors. All explained here:

    The Out Of Gamut Overlay in Photoshop and Lightroom
    In this 25 minute video, I'll cover everything you need to know about the Out Of Gamut (OOG) overlay in Photoshop and Lightroom. You'll see why, with a rare exception, you can ignore this very old feature and still deal with out of gamut colors using modern color management tools.

    YouTube:
    High resolution: http://digitaldog.net/files/OOG_Video.mp4

    Not at all difficult to create them or see the differences given proper tools to do so: take a colorful image in raw, render and encode into ProPhoto RGB, plot in 3D the image gamut compared to Adobe RGB (1998).
     
  11. digitaldog

    digitaldog Andrew Rodney

    MelissaRGB is the name of only one color space used in one place in LR (although you can make them to use in Photoshop etc); the Histogram shown in Develop module. That's ProPhoto RGB gamut (primaries) with an sRGB tone curve (not gamma). It isn't the color space used for processing. It reflects the current rendering settings within that converter (and ACR). It's not a raw Histogram nor tell us anything about raw in that respect. You can or course soft proof and update the Histogram based on anything you have profiles for to select.
     
  12. I think that's good advice, and often overlooked by colour-accuracy purists.

    How many real-world Cyans hit or exceed the CMYK printing space? How many real-world reds and greens go out of gamut in sRGB? And does it really matter if that red pillar box is a shade out on screen or in print? Royal blues might well be problematic, but unless you have that particular piece of cloth in front of you, who's going to know?

    It really only concerns e-commerce that colours are accurately presented. For the rest of us it's a nicety that probably doesn't warrant the trouble or expense.
     
  13. digitaldog

    digitaldog Andrew Rodney

    It is a great idea, never overlooked by color purists who have the tools and knowledge to colorimetrically analysis color images against color spaces. Tell us how you propose your readers do this, I'll point to the tool to do so: CHROMiX ColorThink

    Is color accuracy purists another term for professional, or someone who strives for the best quality image data to process and print? I suppose some amateurs who have no idea how to 'look at the kinds of images before you shoot to chose a color space' should stick with sRGB front to back workflow rather than learn how to properly evaluate scene gamut with working space gamut.
    The question as placed makes no sense and shows a misunderstanding of basic color management. The images are all RGB due to the fact every capture device is that color model. Cyan shows up after conversion to an output color space based on the CMYK color model and output profile used. Until that point, there's no cyan to deal with and the final cyan for output hasn't been defined or applied. So the question makes no sense. Do you wish to see RGB image data of 'real life' images that exceed the gamut of a defined CMYK (not all CMYK) printers? Ask with specifics. EDIT: BTW, got a Macbeth ColorChecker? The cyan patch falls outside sRGB color gamut! :eek:
    Billions potentially. See one example and a thread that might explain to you, if you read and understand it, exactly the answer:

    Re: "sRGB is enough": Photographic Science and Technology Forum: Digital Photography Review

    FACT is, no printer can produce all of sRGB. That is, sRGB has a color gamut in portions of it's color space that exceed every printer on the planet.
    FACT is, those who wish to capture and reproduce all the possible colors they are able to, shoot raw and render then encode in the largest gamut working space they can. There is ZERO downside to this workflow and only a downside to encoding into a smaller working space (clipping of colors captured that can be reproduced).
    IF you're a rank amateur and don't know anything about this topic of color, color gamut etc, stick with sRGB; JPEG on the camera, and everywhere else. IF and when you decide you'd like to up your imaging gamut and utilize more of the data you were able to produce and use, study some basic aspects of color management.
    Speak for yourself not others, don't comment on color accuracy; you're not there yet. After the other two video's referenced that explain this stuff thus far, you can learn about color accuracy, what it means, how it's measured and reported:
    Delta-E and color accuracy

    In this 7 minute video I'll cover: What is Delta-E and how we use it to evaluate color differences. Color Accuracy: what it really means, how we measure it using ColorThink Pro and BableColor CT&A. This is an edited subset of a video covering RGB working spaces from raw data (sRGB urban legend Part 1).

    Low Rez:
    High Rez: http://digitaldog.net/files/Delta-E and Color Accuracy Video.mp4
     
    Last edited: May 2, 2019
  14. So many things I shoot look like this, so you can see why I don't agonize over color space. I also shoot black parts on light backgrounds. The last thing I shot had a couple red and green LEDs as the most colorful thing in the shot. Even the colorful things I shoot personally are rarely brightly colored. And compressed jpegs are just fine, in fact my client would be annoyed if I used anything else. I'm pretty sure only photographers, printers and glossy magazine people lose sleep about color space. Few people today, unless you're working in a specific (and hopefully high $$) environment, have the experience or education to know the difference between sRGB and anything else. (FWIW, I do hope most of you aren't trapped in a monochrome world like this!)

    shuttlebush.jpg
     
  15. digitaldog

    digitaldog Andrew Rodney

    No one needs to agonize over color spaces from raw. They simply need to select one. There is one that's sufficiently large, some raw processors utilize it (a variant in a differing TRC), many allow you to encode into it without clipping: ProPhoto RGB. The object can be totally neutral or super colorful; no difference: color spaces are containers for numbers. You don't have to fill the container. But if the container isn't large enough to fit the contents, you have to clip that data to place it into the container. There's zero reason to do so clipping. And lots of reasons not to do so.
     
  16. All e-commerce is done using the sRGB colour space. It would be foolish to use anything else for internet use. So even (most) colour professionals need to compromise their colour management into that space.

    I'm certainly not suggesting not to shoot RAW, just that agonising over colour spaces might not be a high priority for many casual, and not so casual shooters.

    And if you have a RAW file, why would you bother to put it into the ProPhoto 'container' when there's no output device that can display that gamut?
     
  17. I've been shooting more RAW lately and have discovered that not all RAW converters are created equal. But, if you have RAW, you can take advantage of whatever improvements come along. Along with whatever color space you want.
     
  18. More headroom for grading.
     
    digitaldog likes this.
  19. In what way?
    The RAW file contains all the colour information that's available from the sensor. So a ProPhotoRGB conversion is simply an intermediate stage and, presumably, a degradation from RAW.
    You have the RAW file, and a monitor profile. Surely it makes more sense to convert the raw directly to the monitor space for editing? Such that you have a manipulation matrix that's a single step, rather than converting to ProPhoto first, and then to whatever output profile is needed.

    How does conversion to ProPhotoRGB get you any closer to the desired practical output space? Your raw file is as good as it gets - and according to one of the above links contains 'imaginary' colours that can't be seen even if you can find a display with primaries well outside of its own boundaries. A good trick for a plain old set of dye filters stuck over a slice of silicon!

    No magic monochromatic primaries sitting well outside of the CIE horseshoe, just some RGB subtractive filters of finite width.
     
    Last edited: May 2, 2019
  20. digitaldog

    digitaldog Andrew Rodney

    Surely not. It's why RGB working spaces are divorced from the display.
     

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