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Author Topic: Avoiding color management when printing from Photoshop on Windows  (Read 21121 times)

r010159

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Re: Avoiding color management when printing from Photoshop on Windows
« Reply #20 on: September 02, 2015, 02:53:09 pm »

Interesting results. I have compared a standard RGB profile where a color patch chart was printed using managed color within PS. The target for the RGB profile was printed using the Adobe print utility. The same color patch chart was printed using the CMYK profile through PrintFab. The CMYK target was  printed using what others here are calling the "null profile" approach to disabling color management within PS. In both cases the printed color managed target was compared to the reference values provided by the target generation software for the color patch chart used in the comparison. Other than a subtle green tint to the PrintFab print, both Delta-E error report compared favorably. I have no reason to believe the profile generation software used in both cases is at fault.

>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>

Test Chart printed as CMYK file with PrintFab, using Photoshop color management with the built CMYK profile.

--------------------------------------------------

dE Report

Number of Samples: 418

Delta-E Formula dE2000

Overall - (418 colors)
--------------------------------------------------
Average dE:   3.73
    Max dE:  10.58
    Min dE:   0.40
 StdDev dE:   1.94

Best 90% - (375 colors)
--------------------------------------------------
Average dE:   3.24
    Max dE:   7.00
    Min dE:   0.40
 StdDev dE:   1.34

Worst 10% - (43 colors)
--------------------------------------------------
Average dE:   7.99
    Max dE:  10.58
    Min dE:   7.00
 StdDev dE:   0.76

--------------------------------------------------

Test Chart printed as RGB file with Epson driver, using Photoshop color management with an RGB profile created with same tools.

--------------------------------------------------
--------------------------------------------------

dE Report

Number of Samples: 418

Delta-E Formula dE2000

Overall - (418 colors)
--------------------------------------------------
Average dE:   3.96
    Max dE:   7.08
    Min dE:   0.90
 StdDev dE:   1.21

Best 90% - (375 colors)
--------------------------------------------------
Average dE:   3.72
    Max dE:   5.64
    Min dE:   0.90
 StdDev dE:   1.03

Worst 10% - (43 colors)
--------------------------------------------------
Average dE:   6.08
    Max dE:   7.08
    Min dE:   5.64
 StdDev dE:   0.33

--------------------------------------------------
--------------------------------------------------

>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>

The results would be better compared without the green tint in the result with PrintFab. But I do not have a verified RIP available to me. Perhaps this unorthodox technique only works for PrintFab? I will try to replicate Andrews results. This should provide me with a more definitive result.

I will say here both printed charts I used for comparison, one using a CMYK profile with the PrintFab route, and the other using the RGB profile generated through the Epson driver, did compare favorably. Both results did visually compare. There were no obvious difference to my eye until I carefully compared the two side-by-side. Looking very closely, I did see some differences.

Bob
« Last Edit: September 02, 2015, 03:11:50 pm by r010159 »
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Ferp

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Re: Avoiding color management when printing from Photoshop on Windows
« Reply #21 on: September 03, 2015, 06:05:00 am »

OK, I've done Andrew's test.  I took a simple 288 patch one-page chart, converted it to the printer profile for the paper in question, and printed using both Photoshop with the "null profile" setting and also ACPU.  Below is the delta E result.  Measured in Match3 3.6.2 using an i1 Photo V1 and compared in Measure Tool 5.0.10.  Essentially they are the same.  I've also done a couple of real prints, and as you'd expect, I can't spot any difference.

This demonstrates that Windows and Mac are quite different.   The "null profile" setting doesn't work on a Mac but it does on Windows, at least at the moment.  I'm sure that I read somewhere that the Photoshop warning that you get in Windows about the "null profile" setting is just to have similar messages across the two OS, even if the actual behavior is different.  This confirms the correctness of that statement, whoever said it (I think it was Jeff Schewe).  In MacOS you have to use Print Tool I guess.  In Windows you can use Qimage, although at present you don't have to.

Thanks to all for helping clarify this and for Andrew for suggesting how to test it.


--------------------------------------------------
dE Report
Number of Samples: 288
Delta-E Formula dE2000

Average
--------------------------------------------------
          Total:  0.19
  Best 90%:   0.16
Worst 10%:   0.43

Sigma
--------------------------------------------------
          Total:  0.11
  Best 90%:   0.08
Worst 10%:   0.09

Maximum
--------------------------------------------------
          Total:  0.64
  Best 90%:   0.34
--------------------------------------------------
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RHPS

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Re: Avoiding color management when printing from Photoshop on Windows
« Reply #22 on: September 03, 2015, 07:15:37 am »

As an occasional PrintFab user (I only use it for panoramas to overcome the 95cm limit on the 3880) I have followed this thread and other PrintFab related threads with interest. I have always found the "null" method clumsy, and consequently I have used PrintFab in exactly the same way that I use the Epson driver. I just set PrintFab to "No correction" and then let Photoshop manage colours. Naturally the (RGB) profile is generated from targets printed using PrintFab. This method gives me the same kind of accuracy as I would expect from using the Epson driver - no better, no worse.

This thread prompted me to do a comparison of the two ways of printing using PrintFab on the Windows platform. I wasn't prepared to waste good paper so I only printed my version of the ColorChecker24. I printed once using the conventinal "PS manages colors" way and once using the PrintFab null method. For the latter I used AdobeRGB(1988) as the document and printer profiles. Comparing the two prints in MeasureTool this is what I got.

DeltaE2000

Average

Total            0.56
Best 10%      0.47
Worst 10%    1.15

Maximum

Total            1.56
Best 90%      0.87

What I found interesting is that the biggest differences are in the two darkest greys with Photoshop giving lower L values. The Photoshop print was done with BPC off. PrintFab doesn't have an option for BPC but this suggests to me that PrintFab is using BPC by default. with no option to turn it off.

This experiment, although by no means definitive, convinces me that the best way to use PrintFab is to truly let Photoshop manage colors. This gives the benefit of soft-proofing and control over BPC. Avoiding color management in Photoshop then becomes academic.
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Ferp

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Re: Avoiding color management when printing from Photoshop on Windows
« Reply #23 on: September 03, 2015, 08:14:11 am »

This experiment, although by no means definitive, convinces me that the best way to use PrintFab is to truly let Photoshop manage colors. This gives the benefit of soft-proofing and control over BPC. Avoiding color management in Photoshop then becomes academic.

If you've created an ICC for printing through PrintFab, then surely you can soft-proof in Photoshop no matter which program handles CM?  Surely the two CM engines are not that different?

But I agree with your basic conclusion.  Although I didn't want to burn through too much ink and paper either on this exercise either, in the lead-up to doing these measurements I did some test prints comparing CM in PrintFab and CM in Photoshop and I couldn't pick the difference.  Which is broadly consistent with your measurements, although I'm not sure that my test prints are a good indicator of any differences over BPC.  But it seems like we have a number of options.
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RHPS

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Re: Avoiding color management when printing from Photoshop on Windows
« Reply #24 on: September 03, 2015, 08:57:03 am »

If you've created an ICC for printing through PrintFab, then surely you can soft-proof in Photoshop no matter which program handles CM?  Surely the two CM engines are not that different?
You're right of course. What made me think this way is that (as far as I can tell) it isn't necessary to install the profile on the system for it to be used by PrintFab. My profile was generated in Argyll so I had to specifically install it to use it in PS.
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Ferp

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Re: Avoiding color management when printing from Photoshop on Windows
« Reply #25 on: September 03, 2015, 11:02:58 am »

You said that you found the "null" method in Photoshop clumsy, but I find turning off CM in PrintFab not entirely intuitive or fool proof.  To deal with this I guess there are two options. 

(i) Print from Qimage, which can save driver settings such as CM Off as printer presets, unlike Photoshop will seems to have partial recall and partial amnesia about printer driver settings.  Although that's then yet another CM engine, and I find the differences between Qimage's LCMS engine and the Adobe engine to be noticeable at times, albeit small. 

(ii)  Don't import the ICC into PrintFab, just install it in the OS and use it in Photoshop to soft-proof and convert when printing.  If you do this, then you're using a paper definition in PrintFab that doesn't have the ICC data and PrintFab will complain about it each time you print, but you can at least guarantee that CM is off I guess.

I'm not sure which CM engine to use.
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RHPS

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Re: Avoiding color management when printing from Photoshop on Windows
« Reply #26 on: September 03, 2015, 11:58:19 am »

I prefer your option (ii). It's true that PrintFab puts up a warning that has to be accepted, but if you use the null method then PS throws up a warning. I print from PS all the time and my paper presets in the Epson driver all have No Color Management so my workflow is the same for both drivers.
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r010159

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Re: Avoiding color management when printing from Photoshop on Windows
« Reply #27 on: September 03, 2015, 01:30:13 pm »

Interesting. FWIW I cannot use this method using a CMYK profile. The  CMYK color spaces, which is one of the CMYK standard printer gamuts, has a gamut much less than AdobeRGB.

UPDATE: I have printed a target from within Photoshop using the "null" profile method, and then again using the Adobe print utility. Visually, the print from ACPU has some colors that are more chromatic then the ones printed from Photoshop. But it takes a very close examination to tell this difference.

All I did too see similarities between the two printed charts is measure and run the results through ColorThink. This is what I ended up with:

--------------------------------------------------

dE Report

Number of Samples: 418

Delta-E Formula dE2000

Overall - (418 colors)
--------------------------------------------------
Average dE:   0.78
    Max dE:   2.51
    Min dE:   0.10
 StdDev dE:   0.40

Best 90% - (375 colors)
--------------------------------------------------
Average dE:   0.68
    Max dE:   1.27
    Min dE:   0.10
 StdDev dE:   0.26

Worst 10% - (43 colors)
--------------------------------------------------
Average dE:   1.65
    Max dE:   2.51
    Min dE:   1.28
 StdDev dE:   0.33

--------------------------------------------------
--------------------------------------------------

As you can see, the worst 43 colors have a minimum Delta-E of 1.65, which is a visible difference. I think this in part is due to the chroma differences between the two prints. Note also the average of the 375 majority of colors are barely discernible, with a minimum Delta-E of 0.10. So you see that PrintFab is doing something to the colors it prints even when its color management is disabled. I suspected this from previous tests of mine. But whatever its doing, I have been able to get relatively good profiles from the "null" Photoshop method, except for a subtle green-cyan tint to a good part of the grey scale.

Just for shits and giggles, I will build a profile from the prints made using ACPU. I wonder if the green "tint" will be measurably reduced?

Bob
« Last Edit: September 04, 2015, 01:06:22 am by r010159 »
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Ferp

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Re: Avoiding color management when printing from Photoshop on Windows
« Reply #28 on: September 04, 2015, 08:57:36 am »

@RHPS:  You said that you were only using Printfab to overcome the 37.4" limit.  The problem with using Printfab to do this is that you have to reprofile, and these new profiles aren't going to give you exactly the same result.  How much of an issue have you found this?  Did you vary the ink limit?  Did you print the ink limit strip as part of reprofiling?

@Bob: I can't help.  I don't get these problems with RGB profiles and I know next to nothing about CMYK ones.  The differences that you're measuring are not large, but I don't doubt that you can see them.  Either the "null profile" method doesn't work as well for CMYK, or there's something about Printfab's handling of CMYK which is not right.  It is still a beta after all.  I see that you're looking at other RIPs, but if you want to pursue this for Printfab, you're probably going to be better off asking these questions on the Printfab support forum.
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RHPS

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Re: Avoiding color management when printing from Photoshop on Windows
« Reply #29 on: September 04, 2015, 09:38:11 am »

@RHPS:  You said that you were only using Printfab to overcome the 37.4" limit.  The problem with using Printfab to do this is that you have to reprofile, and these new profiles aren't going to give you exactly the same result.  How much of an issue have you found this?  Did you vary the ink limit?  Did you print the ink limit strip as part of reprofiling?
I started to use PrintFab for printing panoramas canvas when I wanted the extra length. For my canvas profiles I started from scratch, with the ink limit strip, and then printed the targets using ACPU. I am very happy with the results that I get this way so I use PrintFab for all my canvas prints, even if they are under the Epson driver limit. PrintFab is certainly not the easiest application to set up and generate profiles for; but, once it is set up I find that using it in the same way as the Epson driver it is very easy especially now that they have incorporated the Print Preview facility.
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RHPS

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Re: Avoiding color management when printing from Photoshop on Windows
« Reply #30 on: September 04, 2015, 10:02:07 am »

So you see that PrintFab is doing something to the colors it prints even when its color management is disabled. I suspected this from previous tests of mine.

I'm a bit confused by this. Did you print both targets using PrintFab as the "driver" with its color management turned off? If so then surely PrintFab would behave in the same way for both conditions - the difference would only be between PS and ACPU.

As an aside, in an earlier post you gave a comparison between prints made with two different profiles. What image did you print for this exercise? I get the impression that it was a profiling target. If so then I think you need to revise your method. A profiling target will contain maybe 50% or more patches that are out of gamut for your printer so the rendering of these patches only tells you about the gamut boundary, not about accuracy.

But whatever its doing, I have been able to get relatively good profiles from the "null" Photoshop method, except for a subtle green-cyan tint to a good part of the grey scale.

I hate to say this, but if I had even a subtle green-cyan tint in my greyscale I wouldn't consider that I had a relatively good profile.

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Ferp

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Re: Avoiding color management when printing from Photoshop on Windows
« Reply #31 on: September 04, 2015, 10:15:34 am »

For my canvas profiles I started from scratch, with the ink limit strip, and then printed the targets using ACPU. I am very happy with the results that I get this way so I use PrintFab for all my canvas prints.

Perhaps I can ask a more specific question or two.  Did you find the ink limit strip much help in determining the ink limit?  Because I didn't.  So I stuck to the default.

Prints using Prinfab and its profile seem a little darker and more saturated than using the Epson driver.  I guess you could bring Printfab closer to the OEM driver by lowering the ink limit from its default.  But I'm not sure what the point of that would be.  At one level it doesn't matter because you can soft-proof the outcome and adjust to taste.   It sounds like you haven't done this comparison, but given the differences I found, I'd be interested in whether you varied the ink limit from its default and if so, what to.
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RHPS

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Re: Avoiding color management when printing from Photoshop on Windows
« Reply #32 on: September 04, 2015, 11:36:05 am »

Perhaps I can ask a more specific question or two.  Did you find the ink limit strip much help in determining the ink limit?  Because I didn't.  So I stuck to the default.

Prints using Prinfab and its profile seem a little darker and more saturated than using the Epson driver.  I guess you could bring Printfab closer to the OEM driver by lowering the ink limit from its default.  But I'm not sure what the point of that would be.  At one level it doesn't matter because you can soft-proof the outcome and adjust to taste.   It sounds like you haven't done this comparison, but given the differences I found, I'd be interested in whether you varied the ink limit from its default and if so, what to.
I did find the ink limit strip useful. For my canvas I found that I could go to 300 without visble bleeding or blocking of shadows. For my recent experiment I used a very cheap (and nasty) RC paper. For this paper I couldn't go above 150 without producing nasty artifacts. I had already profiled this paper using the Epson driver and I can't say that the rendering is very different between the two profiles.
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r010159

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Re: Avoiding color management when printing from Photoshop on Windows
« Reply #33 on: September 04, 2015, 04:04:23 pm »

I'm a bit confused by this. Did you print both targets using PrintFab as the "driver" with its color management turned off? If so then surely PrintFab would behave in the same way for both conditions - the difference would only be between PS and ACPU.

IMO PrintFab is still doing some color manipulation. That is why the "null" profile method and the ACPU both produce respectable profiles. Andrew performed the same experiment using the printer driver in place of PrintFab with significantly different results from what I ended up doing his same test. Due to this and other tests that I have made, I am convinced that PrintFab is doing something to the colors, otherwise "null" profiler method with Photoshop would simply not work in any respect.

As an aside, in an earlier post you gave a comparison between prints made with two different profiles. What image did you print for this exercise? I get the impression that it was a profiling target. If so then I think you need to revise your method. A profiling target will contain maybe 50% or more patches that are out of gamut for your printer so the rendering of these patches only tells you about the gamut boundary, not about accuracy.

I used the same test target in both instances. The target was created from a commonly used printer test photo with a majority of colors in gamut. But this still would not make any difference, for the color management was "disabled" in both cases per PrintFab instructions using the same printer, print paper, and test target.

I hate to say this, but if I had even a subtle green-cyan tint in my greyscale I wouldn't consider that I had a relatively good profile.

Please remember that I have been explicitly following the documentation that came with PrintFab. Right now the maker of PrintFab is looking into this problem to see if I am doing anything wrong. But since that 99% of PrintFab users will use RGB profiles or CMYK profiles for proofing to standards like SWOP, using  the canned profiles, I do not think this a problem they would normally run into.  

But back to your statement, the RGB profile made in the same way is relatively good with any tint virtually unrecognisable. It's the CMYK profile that has a subtle green tint in its middle and darker greys. Other color aspects appear to be right on. I imagine this is not the first instance of a profile ending up with non-neutral greys. But on close examination not as apparent as I see in my examples.

Bob
« Last Edit: September 04, 2015, 04:12:37 pm by r010159 »
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Ferp

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Re: Avoiding color management when printing from Photoshop on Windows
« Reply #34 on: September 04, 2015, 08:10:58 pm »

I did find the ink limit strip useful. For my canvas I found that I could go to 300 without visble bleeding or blocking of shadows. For my recent experiment I used a very cheap (and nasty) RC paper. For this paper I couldn't go above 150 without producing nasty artifacts. I had already profiled this paper using the Epson driver and I can't say that the rendering is very different between the two profiles.

Thanks.  If you ever try this on a non-canvas, non-cheap & nasty paper paper then I'd be interested to hear of your experiences.

IMO PrintFab is still doing some color manipulation. That is why the "null" profile method and the ACPU both produce respectable profiles. Andrew performed the same experiment using the printer driver in place of PrintFab with significantly different results from what I ended up doing his same test. Due to this and other tests that I have made, I am convinced that PrintFab is doing something to the colors, otherwise "null" profiler method with Photoshop would simply not work in any respect.

This is a sweeping statement. There are four possible combinations - Mac vs Win and RGB vs CMYK.  It's not clear which ones your comment refers to.  Andrew's test indicates that it doesn't work on RGB-Mac.  Mine indicates that it does work on RGB-Windows.  That indicates to me that the Mac problem is in fact a Mac problem, and not an intrinsic problem with the "null profile" approach, at least in the case of RGB. 

Your results seem to suggest that it doesn't work on CMYK-Win.  We don't have a CMYK-Mac result to try to isolate the issue, although I strongly suspect that there would be a similar discrepancy.

What I'd do in your case to try to further isolate the problem is do the test printing from Qimage to Printfab, since Qimage has a genuine no-CM option.  You'd also need to turn off all resizing and sharpening.  If that print is close to the ACPU but different to the "null" approach, then we know that the "null" approach is the problem.  If it's close to the "null" approach and different to the ACPU result, then we know that Printfab is the problem.
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r010159

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Re: Avoiding color management when printing from Photoshop on Windows
« Reply #35 on: September 05, 2015, 03:17:07 am »

This is true for at least CMYK.  The "null" method to disable color management in Photoshop works for PrintFab and does not work for the native printer driver. This is all I really care about. You can read my previous posts to find out what process I went through to prove this to myself.  Also, we do  have a Mac example, my Mac. This is the computer I have been using during this time in this conversation.

Bob

PS: Yes, your suggestion was the obvious next step for me. Using disabled color management in Photoline just verified in my previous results.

EDITED 9/5/15 6:17 PM MST I removed irrelevant statements.
« Last Edit: September 05, 2015, 11:19:03 pm by r010159 »
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Ferp

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Re: Avoiding color management when printing from Photoshop on Windows
« Reply #36 on: October 08, 2015, 08:36:10 am »

This thread started out as being about "Avoiding color management when printing from Photoshop on Windows".

I'm not sure how many readers of this forum also read Ctein's latest article on Printer managed color, and especially the comments, and extra especially the comment from Dave Polaschek (from Adobe) near the bottom of the comments section:
http://theonlinephotographer.typepad.com/the_online_photographer/2015/10/photoshop-vs-printer-managed-color-printing.html#comments

For ease of access and preservation, his comments are below in italics.  He was replying to a post questioning whether the null conversion method is using a Photoshop quirk or bug, or is by design.  A lot of this reads as Esperanto to me.  Is there anyone here who can translate it into English?  I find it hard to accept the suggestion that the null conversion technique is "lying about the color space of the image data".   For example, if an image is in AdobeRGB and I use the null conversion technique, the technique says that it's still in AdobeRGB en route to the printer driver, and so it is.

If one day we lose this capability from Photoshop, then so be it.  What isn't clear to me from these comments is whether any changes that Microsoft might make to Windows would mean that Qimage couldn't print with CM off either.  That would be a disaster.

~~~~~~~~~~~~

"Printer Manages Colors guarantees a conversion to sRGB IF you are printing with a color profile attached to your image data. This is how StretchDIBits (which is the bottleneck routine used on Windows operates) works. ICM2, when designed by Microsoft back in the 90s, chose to use sRGB as their interchange space, so any image data with an attached profile, and with ICM enabled fed into StretchDIBits will be converted to sRGB.

Any image data fed to StretchDIBits that does not have a profile attached to it, is assumed by the OS to already be in sRGB (again, if ICM is enabled). So if you send AdobeRGB data in this manner, and want to get correct colors, you need to check the "AdobeRGB" checkbox in the Epson printer driver so the driver can know that you lied to the OS.

We're trying to avoid lying to the OS. So everything gets funneled through sRGB when you print with "Printer Manages Colors" (because ICM is enabled in that case).

When using "Photoshop Manages Colors" we explicitly call SetICMMode(printDC, ICM_OFF), which disables the conversion done by StretchDIBits. It also disables conversions done by printer drivers which "play by the rules." This is why the "null conversion trick" works - there is a color profile attached to the image, but it is ignored by the OS, bypassing a conversion to sRGB (remember, that's the default interchange colorspace for ICM2). If a printer driver were to pay attention to the color profile attached to the image data (in spite of us telling it not to), you would get incorrect color because the image data is not actually in the space described by the color profile attached to that image data.

That is the bug / loophole you are exploiting. You are lying about the color space of the image data, but convincing the system to ignore your lies.

Finally, Photoshop (and Lightroom) also use bits of XPS Printing (aka Metro, aka Direct2D Printing, and probably a few other names I missed over the years), which are normally only available to C# or managed C++ applications, to further tell the driver exactly what we've done with the image data (this was part of an attempt to make double-color-management and other user mistakes more difficult). We negotiated this protocol with Epson, Canon and HP during the CS3-CS4 development cycles, and got it debugged during CS5 and CS6. Photoshop and Lightroom are, to my knowledge, the only two applications mixing GDI printing (StretchDIBits and DEVMODEs) with XPS printing and the XPS Print Ticket. But if you want no color management at all, you really should be printing from Photoshop CS3 or earlier where that option is explicitly available, rather than lying with the "null conversion hack."

It is possible that a printer driver (such as the "Print to XPS" driver which I have used for testing) will listen to the SetICMMode() call made, AND listen to the information in the XPS printing calls. In this case, the lies made to the OS and driver by way of the "null conversion hack" will be caught, and will lead to incorrect color. Thus the warnings I have asked Ctein to attach to people who are trying to circumvent the system. Microsoft has hinted about dropping support for GDI at some point in the future, and when that happens, the hack will die for sure because all image data in XPS is tagged with a color profile, and there is no way to shut ICM off.
"
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Ernst Dinkla

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Re: Avoiding color management when printing from Photoshop on Windows
« Reply #37 on: October 09, 2015, 09:29:13 am »

More on topic here I transferred this message from another thread on LuLa. Given what I see in driver color management choices I find it hard to believe that Windows shrinks everything to sRGB at some point in the cm route.

There's no intention to go the printer color management route here with my HP Z3x00 printers. I am using Windows and Qimage Ultimate and its color management. The integrated calibration and profiling available on the printers + the default profile creators + the optional profile creators were satisfying so far for photography and already give a choice in profile tastes that can even be widened to more profile creators as the measuring data can also be exported as CGAT.

I am curious though on the choices within printer driver color management on OS-X and Windows. I understand that in OS-X and selecting Colorsync the printer driver will use the OEM ICC profile that corresponds with the chosen media preset, rendering choice is absent. The same ICC profile would be used in application color management for that paper if no custom profile exists. In the other choice it will use LUTs in the driver itself that correspond with the chosen media preset and no use of the Colorsync color engine then. Ctein used that last one.

In my HP Z Windows driver PCL3 choices I see a selection for Application Managed Colors and Printer Managed Colors, the last gives a choice for the Source Profile; sRGB or AdobeRGB, say the color space assigned to the image you want to load. There is no choice for the Windows color engine ICM-WCS or a vendor matching system there. I had no clue what it uses then. It is similar for the Postscript PS3 driver but the Source Profile choices goes up to 4 for RGB and includes way more CMYK color spaces. Both can be set in view of PS PDF documents with both RGB and CMYK aboard. I think the choices of source color spaces are defined by the printer language, PCL or PS, and the limitation in source profiles supported is set there. I can not imagine that they all are converted to sRGB before going into driver color management as Ctein and others suggest for Windows' printer color management. It is more likely the printer language that defines the transfer states.

In the Printing Preferences>Advanced Document Settings tab/menu of both the PCL3 and PS3 driver there are choices for Graphic>Image Color Management>ICM method: ICM disabled, ICM Handled by Host system (ED: Windows I guess), ICM Handled by Printer, and PS3 only; ICM Handled by Printer using printer calibration. There is also an ICM Intent range of choices; graphics, pictures, proof, match, for all the 4 ICM management choices. The default setting in the driver is ICM disabled. My guess is that this range of choices matches the two choices Ctein was confronted with when he went  for Printer manages color; Colorsync or Epson Color matching. HP offers more choices though, at least in my Windows system. The ICM choices represented in this menu of the driver only come in action if the user selects Printer managed color on the other menu page, I can not interpret it otherwise. Not that HP explains that carefully and worse, the driver's defaults are Printer Manages Color + ICM disabled, which should result in no CM at all. In the beginning I had the impression that it only applied to documents like PDFs etc but meanwhile I learned it works for Printer manages color on all what is thrown at it.

It would be nice to get a better understanding of what happens under the hood with those choices and where the differences are between OEM drivers + their OS-X and Windows versions. Again, not to use that CM route for Tiffs etc but for an understanding of the method. For PDFs etc with known RGB + CMYK color spaces assigned the PS3 driver offers at least a kind of RIP CM route this way and I know it is used by Z users for that task.

Met vriendelijke groet, Ernst

http://www.pigment-print.com/spectralplots/spectrumviz_1.htm
December 2014 update, 700+ inkjet media white spectral plots
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