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Participant
January 14, 2009
Question

Assign- Convert - Proof Colors

  • January 14, 2009
  • 51 replies
  • 15476 views
In Photoshop, I can choose to assign or convert to profile. This seems straight forward, I think.

I was given images in ProPhoto RGB color space (8 bit). Just as a test, I did two things. I created a Proof setup that used Adobe RGB and Peceptual Rendering intent. Then, I also went to Assign Profile. Both cases the image was darker and lacked detail (given the smaller color space)...

My working space for RGB is Adobe RGB with perceptual rendering intent.

Next I turned the proof colors off and I converted the file to Adobe RGB. In this case, the color changed very little (was not dark at all).

I thought I understood that if you assign a profile, the appearance on screen will differ (and the numbers will stay the same), If I convert, the numbers actually change.

question: Why would the image look very dark when I was assigning the profile, but look the same as the original when converting?
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    51 replies

    Was DYP
    Inspiring
    January 17, 2009
    Afraid to think outside of the box are we?
    January 18, 2009
    >Afraid to think outside of the box are we?

    What's
    i that
    supposed to mean? What's this got to do with any boxes? And what out-of-box experience would you wish to propose? Dan Margulis'?

    Try again.
    Ramón G Castañeda
    Inspiring
    January 17, 2009
    :)
    Ramón G Castañeda
    Inspiring
    January 17, 2009
    For the sake of clarity, it must be pointed out that the OP has changed his user ID from csullivan to junglebunk . This information is necessary to understand the references to csullivan in replies to his posts.
    Ramón G Castañeda
    Inspiring
    January 17, 2009
    By now it's clear that Mr. Margulis is fossilized in the stone ages.

    There is no doubt that he can be a magician when it comes to color correcting images for press printing, but his stand on color management has no place in today's technology.

    Unfortunately, my first attempt to get serious in the use of Photoshop years ago was through his Professional Photoshop book. I can now say in good conscience that my unfortunate and uninformed decision to read his book at that point set me back several years, or at least it delayed my understanding of color management by several years. :(

    DeMargulisation ( Entmargulisierung) is an essential step in understanding color management.
    January 17, 2009
    >DeMargulisation (Entmargulisierung) is an essential step in understanding color management.

    Das stimmt, mein freund!
    Ramón G Castañeda
    Inspiring
    January 17, 2009
    > if we Convert AdobeRGB to sRGB -- and back again --

    then that "we" stands for a group of totally deranged individuals. :|
    Participating Frequently
    January 16, 2009
    ASSIGNING "FALSE" PROFILES

    then you always got the calibrated monitor issue -- if the genius Assigning profiles in Photoshop has a good monitor profile enabled to make a better call -- or if his monitor is so off he is actually hosing good color

    +++++++

    Color Management is very simple in theory, but easily confused by smoke and mirrors and misinformation

    I believe if one takes a few minutes time to learn the core basics of how profiles work, most of the rest will fall into place under commonsense logic and following the chain for the broken link

    there is rocket science involved, but if the geniuses do their job, most of us will never have to think past the simple basics:

    HONOR the Source Space

    CONVERT to Target Space (or workflow)

    Use GOOD PROOFING PROFILES for our devices
    Participant
    January 16, 2009
    OK Marco,

    I overstated my stance.

    But oddly enough, some of my new responsibilities include finding out exactly what went wrong, where in process and with very little (if any) contact with the users. It makes it extremely difficult.
    Was DYP
    Inspiring
    January 16, 2009
    I found the whole article.

    http://www.ledet.com/margulis/Makeready/MA48-Fate_and_False.pdf
    Was DYP
    Inspiring
    January 16, 2009
    Let me throw this into the mix. There is a case for assigning (false profile).

    http://www.accessmylibrary.com/coms2/summary_0286-781223_ITM
    January 16, 2009
    >There is a case for assigning (false profile).

    There is no such thing as a "false" profile.

    Profiles are real and quite "true". This preposterous terminology was coined by Mr. Margulis, and as far as I know is only used by him and his acolytes.

    When you assign a profile, you assign a profile. Period. There is absolutely nothing "false" about it.

    The assigned profile may work or not with the image, visually speaking. This "false" appellation is bunk.
    Participant
    January 16, 2009
    All,

    The conversation has been great.

    When one is part of a large industry such as graphic arts, you will deal with all kinds (those who are first time graphic designers, free lance operators, etc.)

    Your assumptions are that each of these individuals will understand the dialog boxes which appear. What I was hoping was that I would be able to give a good explanation to those who are faced with such dialog boxes. I am never one to say "DO THIS BECAUSE." I am one who wants explain exactly what will happen if (you make the wrong choice)... and I have not come up with a very good example to explain TECHNICALLY what will happen if they choose to do such things (heck, many people have the ask check-boxes off in the color settings)

    The prime example is having to deal with those who like to use the new features of just realeased software. The why of such "effects" don't output is just as important as why to do things a different way (Remember when Illustrator transparency first reared its ugly head?)

    >>Unless one is still unclear about the distinction...in which case it's better to admit it.>>

    You missed the point completely. Knowing and using the correct workflow and processes is a VERY, VERY small part of the equation. Understanding what happens when you don't is more important
    January 16, 2009
    >Knowing and using the correct workflow and processes is a VERY, VERY small part of the equation.

    Definitely
    i not.
    >Understanding what happens when you don't is more important.

    How do you understand that if you don't understand what needs to happen so that things are done as intended?