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I don't know much about color management even though I read a lot about it today. I know a computer needs calibration in order to render colors accurately, but as an amateur, I don't have the tools or the budget for that. And I'm not sure it would solve my problem anyway.

All I need is, within my screen and its color inaccuracies that I'm well aware of, to be sure that the colors are ate least visually in sync between softwares so that I can trust the internal colors when I work. It's ok at this point if those colors are not necessarily correct out of the box (printing), as long as they are consistent inside the box (editing).

So here is my actual problem:

I try to reproduce, in photoshop and Illustrator, some illustrations that I have in a PDF file. But the same PDF file renders differently within Acrobat DC, iMac Preview and Photoshop. I don't know which one to trust.

I would tend to believe Acrobat is the one to trust because PDF's are native but the result is very vivid for a file that was made to be printed (it seems very "RGB"). The iMac preview software however seems strangely the most "accurate" (it does look like the physical prints I have of the same illustrations).

Left = iMac Preview software, right = Acrobat DC

enter image description here

As you can see, the rendering discrepancies from the same reference PDF file I use are huge. So, I don't know which one to trust. The left one is so close to the actual physical cards bit it's just a preview. The right one is less faithful to the real thing but it is native Acrobat PDF. I think I should logically stick with Acrobat DC but my eyes keep telling me otherwise.

Here are my settings( I'm in Central Europe):

I set the color workspace as CMYK within Photoshop and Illustrator because, I would like to print the result when finished (I'm not there yet so that's not the point right now).

iMac colorsync:

  • profile : sRGB IEC61966-2.1

Photoshop Edit/Colors:

  • RVB : sRGB IEC61966-2.1
  • CMYK: Coated Fogra39
  • Grayscale : Dot Grain 15%
  • Direct tone: Dot Grain 15%
  • Color management: Keep the incorporated profile

Illustrator Edit/Colors:

  • RVB : sRGB IEC61966-2.1
  • CMYK: Coated Fogra39
  • Color management: Keep the incorporated profile

Acrobat DC Preferences/Color management:

  • Options: Pre-press for Europe 3
  • RVB : sRGB IEC61966-2.1
  • CMYK: Coated Fogra39
  • Grayscale : Dot Grain 15%

The iMac preview software however doesn't want to let me set up anything when I use a PDF. The proof options are greyed out when previewing a PDF.

So, Is there anything (else) I should do (or something I do wrong) in terms of basic settings ? Any advise that is realistic in my case (buying a tool or hiring a pro to calibrate my computer for a few hundred of euros just for editing a few files as an amateur is overkill).

I totally get that my screen will not render the same way as my printer or as any other screen. But I don't get why, within the same screen different pieces of picture dedicated software would render colors so differently when set up the same way. I really tried to understand but it's beyond me. Any help would be appreciated.

Thanks.

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    At minimum, we need to know the input profile (the one embedded in the original document) & what your output intent is, precisely.
    – Tetsujin
    Dec 19 '20 at 12:51
  • Well, I told you everything I know. Anything else I don't know where to find that (where can I see the input profile ?) The output is just printing at home but I haven't discussed this part because at this point, all I want is to know which piece of software to trust in order to replicate its colors within the computer. I mean: I'm re-drawing the cards but I need to know which piece of software is showing me the accurate colors I need to use as a reference for my own design. printing is not the point yet. And if it's not about the software, what is it about ? A setting ? Which one ? Dec 19 '20 at 16:21
  • I had to go into the details but may question is fairly simple actually: If I want to redraw accurately something on my computer that is shown on my computer and if several pieces of software are showing several results on the same computer, what should I do so that my drawing is accurate and faithful in terms of colors to the original file ? The output is not the point at all here, it's just me trying to re-draw something I see but that shows differently according to what software is displaying it. It's all happening on the same screen here. Dec 19 '20 at 16:25
  • Color management is not one thing. Its a tool that can be used in multiple different use cases, not all of the use cases are the same. It can de used to covert values form a system to another, the aim here is to make you see the color the same. But this only works if you hardware is calibrated or even remotely close tho what it is assumed to be. Usecases for this is to make sure two connected moniters show same color, or that what you see is what is printed. IT can be used to present you different colorspaces numeric values as they are or as they are on your system, both are valid uses.
    – joojaa
    Dec 19 '20 at 19:33
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    It can be used to describe a visually pleasing transform that has no intention of keeping the color because it can not be kept. But instead do the best you possibly can, with choice to originbal author how it should be handled. And last but not least it can be totally just tagged and invisible to you.
    – joojaa
    Dec 19 '20 at 19:36
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Garbage in → Garbage out! This is exactly what a uncalibrated system should produce. Inconsistent results. But also note your not telling me the most important part, what is your conversion intent.

Anyway the purpose of color management is to simulate a result. Explicitly it is not geared to make same colors same on all system applications. Indeed it is because of this purpose that they are different! But offcourse a simulation thats done wrong is wrong.

Your screengrabs dont also help because i have no way of knowing what you see. But those differences indeed tell you how much the color can easily vary between two uncalibrated systems.

Simply your software use different color engines that have been calibrated differently. Also we know nothing of how your print service is tuned. Indeed many cheap systems act like rgb systems no point in making cmyk on devices that dont act like cmyk devices.

Think about a similar situation. Lets compare a cheap home piano and a grand concert piano. Which do you assume sounds correct? Which is more likely to be recently tuned? Which needs more tuning? Which has more options when it comes to tuning? Which will when not treated properly work good?

PS: also it is very unlikely that a system would be tuned so that every application is correct. Since many apps are just way too buggy to do that even though both mac and widows is color managed. You would only tune and trust a part of your system. I would not expect all apps to display same even on a perfectly calibrated system especially for CMYK data.

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  • Actually, on a Mac, once you get your correctly calibrated profile set up (& set profiling correctly in such as Photoshop) then you do have system-wide accuracy. I definitely agree with the rest, though. GIGO.
    – Tetsujin
    Dec 19 '20 at 11:31
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    @BachirMessaouri THats the point you can not know. No calibrated system means that the value #d01818 is meaningless. it can be some ssort of red or it might be pink. The numbers have no meaning unless you have a calibrated system
    – joojaa
    Dec 19 '20 at 18:58
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    @BachirMessaouri so simpler a rgb color triplet is not a color. Its a signal to a unknown system.
    – joojaa
    Dec 19 '20 at 19:01
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    @BachirMessaouri the relative and absolute value is only meaningful if your devices know what their values are. Without calibration equipment they do not know this. That is the crux of the issue, if you cant measure your devices all talk about color is meaningless. There are some complications to this when you have colors that can not be handled. Its far from a simple thing. But you can revert to a older method of doing this. Print a sheet of color switch your printer and use that to set colors, wont work if you c change printers but at least you get consistent color.
    – joojaa
    Dec 19 '20 at 19:12
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    @BachirMessaouri but if your system is closed. You can print a sheet of different swatches and choose form those. Its not useful for others but at least its ok for you in this subset of problems. Personally i feel like a hundred or so bucks is a cheap way to deal with this.
    – joojaa
    Dec 19 '20 at 19:17
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This is an approximate guesstimate method of trying to calibrate your workflow. It is not the way the professionals do it & there is much more margin for error...

For home printing you can entirely ignore CMYK, unless your existing images are already in CMYK, in which case you've a bit more approximation to do at the end. Home printers don't use CMYK, they convert internally from RGB, using your printer profile & screen profile, both managed outside of Photoshop.

To see what the image should look like, then you need an accurate colour calibration of your screen. Without that everything, absolutely everything you do is guesswork.

You can have a go at manually calibrating your screen on a Mac by opening Syetem Prefs > Displays > Colour, then hold Opt & Click Calibrate…
In the new screen that opens, make sure the Expert mode is on, then work through each section until you reach the point you can save your new profile.
Because it's a bit hit & miss doing this manually, I'd suggest you do it 3 or 4 times, each time saving a new profile name. At the end, go back to the initial Displays pref & click between them. If you get two or three that look very similar to each other, pick one of those as your profile. Discard the rest. This eliminates some, but not all, of the human error you will encounter trying to perform this task by eye.

Once you have your Display profile established, you can then ignore it. The Mac will look after it for you.

Go to Photoshop & in the Colour Settings prefs Cmd ⌘ Shift ⇧ K set your Working space to sRGB IEC61966-2.1 (you can ignore the others for now.) In Colour Management below, set all three to Preserve Embedded Profiles. Set Mismatches & Missing profiles to Ask.
Everything else should default as follows:-

enter image description here

The logic behind Asking at mismatch or missing is it's a quick way to discover what profile your existing documents have. As soon as you open one, if it's not already sRGB Photoshop will ask you. Tell it to preserve anyway, but you'll at least have a known quantity.

If the images are in any kind of RGB, then preserving that until the end is 'safer' in some respects. I very much doubt they would be in P3, ProRes or even Adobe RGB which can cause issues of perception vs accuracy in an unregulated workflow (but not enough to worry you unless you do this for a living).

If they start in CMYK, then you might have to take a punt. See what it looks like unconverted vs converted to sRGB.
This is going to have to be an artistic decision, because you can't accurately compare between them & CMYK is no use to your home printer.
It would probably be worthwhile printing one as as further test of this rather guesswork part of your process to decide what's best for your overall workflow.

I'd then recommend, from CMYK probably to convert to sRGB (after your tests), from any RGB work in the existing profile. Again, try a test print.

If any of this is as confusing as all heck… welcome to colour management workflows ;)
Professionals have expensive hardware devices to measure all this. Home users have to do a lot of guessing & testing.

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  • H,i and thank you very much for your answer. It is thorough. Yes, it's confusing because we are still taking about the output, the printing and calibration while I don't understand why because it's not about how the colors "feel" but just matching the colors within the computer, independently from what they look like actually.. I'm sorry If you addressed that, as you said, it's hard to understand... Here below a simplification of the problem (I need to use another comment because it's too long). It's idealized but it's exactly my issue. Dec 19 '20 at 17:10
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    You only know what absolute values he used if your workflow is calibrated & correctly profiled. Once you have that, then all eye-dropper values should then agree. The potential discrepancies between eye-dropper values is quite complicated (too much to cover here)
    – Tetsujin
    Dec 19 '20 at 17:17
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    @BachirMessaouri Stop using Preview :) It's for the average non-professional user to view and make minor adjustments to images (rotate, crop, etc.) Preview is not now and never has been a professional-level tool. When considering PDFs in Preview, there are a ton of things Preview wont' support correctly. PDF support in Preview is merely there so PDFs can be viewed, that's all.
    – Scott
    Dec 19 '20 at 18:25
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    If Preview "follows the color profile of your computer" and your computer is not calibrated... that should tell you something.
    – Scott
    Dec 19 '20 at 18:44
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    Knowing your input profile & having the rest of the machine calibrated will go a long way towards solving this. Preview is good at colour-matching profiles, but we're back to GIGO (garbage in, garbage out). You have to have a base point to start from, otherwise anything you do will simply produce random results.
    – Tetsujin
    Dec 19 '20 at 18:45

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