Understanding COLOR PROFILES, ICC.

Discussion in 'Digital Photography' started by ZballZ, Feb 28, 2009.

  1. ZballZ macrumors regular

    Nov 11, 2006
    Understanding the importance of this has come to my attention, since my prints always look different than my retouched images in photoshop. Especially skin-tones are really hard to retouch, and it really frustrates me that the tone is off in the print...

    But I cant really get my head around the best settings for my workflow when it comes to color profiles. As far as I understand, profiles to consider:

    1) The camera has a profile - in my case an Eos Rebel: I have it set to Adobe RGB 1998.

    2) The display has a profile, I work on my MBP set to Color LCD (I have messed around with different ones, but ultimate choose the native one, thinking that it might be more "true")

    3) Photoshop has a profile. And I can honestly say I have always just left these settings alone.

    Now, I know that retouching on a laptop in the first place is a sure mess-up, but this is just the way it is for me at the moment.

    But could someone with more knowledge than me in this matter explain how the camera, display and photoshop profiles interact with each other, and how to work with these in a proper fashion. Do these profiles work on top of each other, or does the photoshop setting rule the others out?

    And ultimately, an explanation to any kind-of-simple way to adjust the display and photoshop to a (better) "true-to-print"-colors would be AWESOME...

    ...any help appreciated, since this really bugs me and my head might explode soon :)

  2. MisterMe macrumors G4


    Jul 17, 2002
    You are going at this all wrong. It is possible for you to select a profile for each element in your workflow that does a passable job. However, you cannot expect guesswork to be a successful strategy.

    The thing that you need to understand is that cameras, scanners, monitors, and printers can drift from their factory specifications. Also, the light in which your pictures are taken, the medium on which your photograph is scanned and printed, and the light in your computer room all affect the colors that you see.

    Rather than counting on guesswork for your color profiles, you should do what the professionals do. Buy a calibration kit and calibrate your camera, scanner, monitor, and printer.
  3. Cliff3 macrumors 68000


    Nov 2, 2007
    SF Bay Area
    Profiles are really a series of mappings that define how color values are rendered by the various hardware devices that consume your file. Hardware devices have color profiles, while image or graphic files are associated with color spaces. It is important to distinguish between a color space and a profile, as your post indicates some confusion on that.

    A color space defines the domain of possible colors that can be rendered. Adobe RGB 1998 (aRGB) is a color space. ProPhoto is another, and it is a larger color space than aRGB in that it contains more possible colors. sRGB is a smaller color space than aRGB. Hardware color profiles are nearly always based on the sRGB color space. Printers might be CYMK or other color spaces, and a very small number of monitors exist that can display most or all of the aRGB color space.

    It sounds like you're shooting jpegs. If not, then the specification of aRGB only governs the behavior of the embedded jpeg which is used to calculate histograms and similar shot analytics. If you save your photos to raw, then they are not associated with a particular color space until they are consumed by Photoshop or Lightroom.

    Since you're using Photoshop, Adobe has provided camera profiles for the Camera Raw/Lightroom software. Those govern the raw conversion process. I shoot Nikon, so Nikon-specific profiles appear in my list. There are Canon-specific profiles too. You can also create your own raw conversion profiles, and that process is discussed here: http://fors.net/chromoholics/support/?w=GettingStarted.

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    I use a colorimeter and calibration software from Xrite to profile my displays. Display profiles are specific to a particular display and the environment in which it is used. There have been previous threads talking about display calibration in various forums on this site.

    Actually, Photoshop (and Lightroom and presumably Aperture too) have a default color space. Lightroom's default color space is ProPhoto, while ACR's is aRGB (and this can be changed on the camera raw screen).

    And rendering for the output device is the final stage of the color management process. Note that I didn't say printing, since the output device might be a computer screen (which lives in the sRGB color space). ICC profiles for specific printer and paper combinations are frequently provided by printer and paper manufacturers and the better printing service bureaus. Soft proofing is the term for previewing printer output on the screen, and articles have been published on the web discussing that subject (not to mention searching Photoshop help for soft proofing).

    Whole books have been written about color management. This is one of the better ones: http://www.amazon.com/Real-World-Color-Management-2nd/dp/0321267222/ref=sr_1_4?ie=UTF8&s=books&qid=1235829831&sr=1-4.
  4. OreoCookie macrumors 68030

    Apr 14, 2001
    Sendai, Japan
    Using Color profiles without at least a calibrated monitor is pointless. The least you have to do to work with color profiles is use a hardware calibration tool to calibrate your screen. That's relatively inexpensive and easy to do. Profiling your camera and your printer is much more expensive and challenging.

    You can use a laptop screen for retouching (with some limitations, especially when it comes to skin tones), but they're plenty for some quick retouches (if calibrated!).

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