Apple and Colour Management – Just When You Thought It Was Safe To Go Out

[Doyle Yoder]

Because I woke up early (at least for me, 8AM is early)... and I've already taken some melatonin and it's beginning to take effect (I'm sleepy... ). 

Printed yet another copy with a Null Transform and visually that matches the 16 bit plugin (I've yet to confirm that with some measurements). I'm hoping that's enough confirmation that all is well with the 16 bit Plugin but damn... these things don't instill a whole lot of confidence in... well, I'm still not exactly sure who it is that I should or shouldn't have confidence in. Apple writes the APIs, it's their job to maintain the codebase and gracefully deal with changes to said codebase so I feel like they deserve a big finger pointed at them but... When ACPU is supposed to solve such problems and it doesn't match something which is.. err... was... um... is??? a known quantity, I start questioning everything. 'Tis frustrating.

Time to sleep so I can look at this with a clear head tomorrow (profiling Innova's IFA-45... very very nice stuff)

ACPU will only print correctly if it is listed in the AppColorMatchingInfo.xml file.

What are your driver settings when printing from ACPU? Specifically under Main/ColorMode:?

Doyle

[Scott Martin]

Which method of printing targets should we trust ?

I propose the null transform trick for most RGB and CMYK (Postscript) printers and the Canon printing plug-in for their large format iPF printers. This approach works 100% of the time on any system.

[Schewe]

I propose the null transform trick for most RGB and CMYK (Postscript) printers....

It won't work with Photoshop CS6. Trying to use the "trick" results in a warning dlog from CS6's Print window.

[shewhorn]

It won't work with Photoshop CS6. Trying to use the "trick" results in a warning dlog from CS6's Print window.

What's it using to identify the profile? If it's just using the name you could always duplicate and rename a profile's file name and internal name.

Cheers, Joe

[Doyle Yoder]

Well I guess the story that 16-bit applications have to use Apple's new printing path has been debunked.

Illustrator CS6 is 16-bit and does not use Apple's new printing path. It print routines still function the same as ILCS5.

[Doyle Yoder]

What's it using to identify the profile? If it's just using the name you could always duplicate and rename a profile's file name and internal name.

Cheers, Joe

Why can't you use ACPU? Answer my question if you are having trouble with it.

Or use Indesign CS6 if you have it. It still allows you to turn off CM with the "Emulate Adobe Indesign 2.0 CMS Off."

Doyle

[shewhorn]

Why can't you use ACPU? Answer my question if you are having trouble with it.

I was going to use it as I've been printing in CS4 with the Canon 16 bit plugin but I've had CS5 on my machine for 1/2 year now and I'd like to get rid of CS4. Knowing that there were some issues with CS5 (I wasn't aware that the 16 bit plugin was exempt from those issues but makes sense that it is) I thought I'd try out ACPU and compare a chart from ACPU and the 16 Bit plugin (on the ipf8300). There was a 12.99 dE2k between the charts.

I just ran a null transform with the regular PS printing workflow to see if that agreed with the Canon plugin and indeed it does... Average dE2k of 0.33 for 1005 patches. So that's encouraging but it leaves me scratching my head as to why I'm getting such different results with ACPU.

[shewhorn]

ACPU will only print correctly if it is listed in the AppColorMatchingInfo.xml file.

What are your driver settings when printing from ACPU? Specifically under Main/ColorMode:?

Doyle

Sorry Doyle... I missed this earlier. I'll double check the AppColorMatchingInfo.xml file tomorrow! Thought I'd changed it but maybe I did it on one machine and not another? Always a possibility.

[Doyle Yoder]

It won't work with Photoshop CS6. Trying to use the "trick" results in a warning dlog from CS6's Print window.

Yes but you can cancel it and still print with the printer profile that same as the assigned profile. Doesn't that work.

[Scott Martin]

It won't work with Photoshop CS6. Trying to use the "trick" results in a warning dlog from CS6's Print window.

Well I need to do some more testing on this and confirm with Adobe's printing engineer but it does appear to work to me.  Sure they warn us that it's not officially supported, and AdobeRGB is hidden but one can assign and print using sRGB for example... Besides the dialog box, what experiences have you that suggest it doesn't work?

While it works great for many users with limited usage, the ACPU has too many problems for someone like myself to consider using. Image resizing and no support for CMYK or grayscale being the biggest issues. There is another application coming soon that will be better, IMO. Can't say more just yet.

[Scott Martin]

Well I finally spoke to Adobe's printing engineer this morning and yes, they've intentionally removed working space profiles from the print dialog box which makes the Null Transform Trick we know and love pretty much dead. That's not to say you couldn't use other profiles to make this trick work but some testing is in order...

[digitaldog]

Well I finally spoke to Adobe's printing engineer this morning and yes, they've intentionally removed working space profiles from the print dialog box which makes the Null Transform Trick we know and love pretty much dead. That's not to say you couldn't use other profiles to make this trick work but some testing is in order...

I’ve talked to them too and the reason they did this was, like removing the no color management option, to make the print process easier on the masses. It wasn’t to piss color geeks off <g>.

You’ll notice that sRGB is still around thanks to Epson, assuming you’ve got an Epson driver installed.

[Scott Martin]

I’ve talked to them too and the reason they did this was, like removing the no color management option, to make the print process easier on the masses. It wasn’t to piss color geeks off <g>.

The removal of working space profiles was specifically to make things easier on Adobe's support team, which is distinctly different from customers.

[digitaldog]

The removal of working space profiles was specifically to make things easier on Adobe's support team, which is distinctly different from customers.

Sorry, that doesn’t make sense to me. If it was no issue for customers, why would they be bugging Adobe Support?

Outside of such rare null profiles, when would a user be selecting these RGB working space profiles in this print module?

[Scott Martin]

Your points aren't lost on me Andrew. I just think there could a more elegant way of keeping all users happy. Photoshop's traditional massive list of profiles in the print dialog contrasts with Lightroom's highly focused customizable menu. Why not have a customizable menu that allows for working space profiles but shows only printer profiles by default? Simplicity and powerful flexibility can exist together - and do in the best GUI implementations.

[digitaldog]

Your points aren't lost on me Andrew.

My only point was that the addition of these profiles are unnecessary for the vast number of Photoshop users and apparently Adobe felt it was confusing and removed them. Just as the removed the NCM option. Other than those tiny few who print targets, it wasn’t necessary. If you look at the 20+ years of Photoshop history, it is really rare to have them remove anything, even stuff that should be removed (or at least fixed, like the Gamut warning overlay).

Photoshop's traditional massive list of profiles in the print dialog contrasts with Lightroom's highly focused customizable menu. Why not have a customizable menu that allows for working space profiles but shows only printer profiles by default?

I’d love to see that. The Photoshop team is moving into that direction as the result of output profiles for the selected printer, at least those in the packages, float towards the top.

[Scott Martin]

Having a bunch of display profiles show up in the print dialog is useless. Hiding working space profiles and custom printer profiles is going to be pretty problematic for a fair number of users I think!

[Tim Lookingbill]

Would this document shed any light on this subject? Help me understand it.

http://developer.apple.com/library/mac/#technotes/tn2035/_index.html

I've been reading up on that after concerns over unexpected behavior changes in my Epson driver interface and how it deals with tagged images out of CS3 Photoshop print dialog using "Printer Manages Color" with my Epson NX400 in Mac OS 10.6.8.

At first in Tiger the Colorsync radio button was selectable over Epson Color Controls in "Color Matching" menu by first selecting "Photoshop Manages Color" in Photoshop print dialog. Now they're both grayed out with Colorsync selected. It's vice versa when "Printer Manages Color" with Epson Color Controls selected and both grayed out.

In Tiger and throughout all the driver updates I always get pretty darn close color matching where at the beginning it required the color space data be in AdobeRGB and using AdobeRGB and 1.8 gamma selected in Epson's Color Management menu.

Upgraded to new computer with OS 10.6 and now it worked having the data converted to sRGB. If I didn't have the right conversion it would show up in print similar to assigning each color space to the wrong data with regards to hue/saturation.

Now after subsequent Epson printer driver updates from Apple with the final in OS 10.6.8, it doesn't matter what color space the data is written printed out of Photoshop. I can edit the image in any color space and the Epson print using "Printer Manages Color" and the AdobeRGB 1.8 gamma Epson setting will render it faithfully in the print.

That document above got me to wonder how and in what spooling format the data of the image in Photoshop is being handed off for Epson to print from where I still get the same color match even with all these on/off driver settings and color space data changes. How is Epson, Photoshop and the image data working between each other in translating the data so it provides this match without "Photoshop Manages Color"? It's like it's generating the data from the color managed display screen dump.

This is the quote from the above Apple developer doc that makes me wonder if Quartz, PDF and Colorsync is getting involved under the hood when using "Printer Manages Color"...

From "Color Model In Quartz" chapter:

PDF color space equivalence

Another simple but very important concept that Quartz inherited from PDF is color space equivalence. An implied rule is that color conversions are necessary only if the source color space is different from the destination. Quartz takes advantage of this simple rule to properly organize the flow of color data through multiple rendering stages:

How is the data being handled and in what format is it being spooled from Photoshop and handed off to the Epson driver to get such close and consistent color matching through all the driver setting/color space changes that don't happen in Safari and Preview where I don't get a color match no matter the Epson setting or color space?

It looks as if there's something going on under the hood I don't think even the Apple and Epson engineers understand.

Correction: I can now get color matching out of Preview using Epson Color Controls and the AdobeRGB/1.8 gamma setting with the image written in sRGB. And now it works with the image written in AdobeRGB.

[Nora_nor]

question: with Preview, you mean the apple program called Preview that comes with macs?

[Tim Lookingbill]

question: with Preview, you mean the apple program called Preview that comes with macs?

Yes.

But to clarify I only get matches printing on Ultra Premium Photo Glossy paper with Premium Photo Glossy selected in the Epson driver Print Settings menu where you set High Speed, Color Photo, etc. I only use the NX400 for low volume printing like on demand business cards runs which look quite good.