Grayscale ICC profiles and soft proofing

Inkjet printing has advanced enormously in the past 15 years. From the expensive Iris giclée printers to our current pigment ink models, all this progress not only improves the maximum reproduction quality attainable on this medium, but also makes it easier to get excellent results without much tinkering.
Published by Fábio Pili on July 26th, 2011. Last updated on April 24th, 2013.
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Sand and wind. © Fábio Pili

Black and white prints have always been a weak spot for this technology. While top quality, fade resistant color inkjet prints could be made in the 1990s—by IRIS printers—or in 2000—when Epson introduced the first affordable pigment printers—getting neutral B&W prints was possible much later, with the first printers that incorporated multiple shades of gray inks and adequate driver support for monochrome output. Before that, only specialized methods were available, and they were both expensive and difficult to master.

Nowadays, it's possible to produce excellent black and white prints on any professional inkjet printer, with quality that easily matches the best chemical darkroom prints on fiber paper. Best of all, 95% of this quality can be obtained by sticking to the printer defaults and a professional paper from the same manufacturer.

Is it all that simple? Yes, it is. Buy an Epson R3000, a pack of Epson Exhibition Fiber Paper, hit print, and select the ABW mode (advanced black and white). Done. You'll be amazed.

Even so, there's still room for improvement. One of the techniques I've explored recently is the use of grayscale ICC profiles for B&W printing.

What are ICC profiles and why do they exist?

ICC profiles, or color profiles, exist to characterize how a particular device reproduces color and, ultimately, to allow software to compensate for that in order to output color accurately.

B&W ICC profiles do exactly that, but use a single table to describe the printer grayscale values, from paper white to solid black. These monochrome profiles allow us to linearize the printer output, compensating for minimal ink batch variations and printer manufacturing inconsistencies.

There are mainly two advantages of working with B&W profiles: output linearization and soft proofing.

Linearization ensures that your printer reproduces tone values evenly throughout the scale, from paper white to solid black. For example, if the 50% percent gray of a particular printer comes out as a 47% gray, we should output it roughly 3% darker to get a perfect tone. By describing a printer, ink, and paper combination through an ICC profile and printing with it, we are able to effectively make output linear.

Soft proofing is the holy grail of digital printing: being able to see in your display the exact simulation of your final printed output. Even though professional Epson, Canon, and HP printers come with dedicated black and white modes, none provide means for accurate soft proofing. This is where building your own monochrome profiles comes in handy.

How to create grayscale ICC profiles

Software and hardware needed:

Color profiled display. It's not possible to accurately preview your printed output without a properly profiled display.

Professional inkjet printer that has a dedicated black and white mode. For example: Epson R2880, R3000, Stylus Pro 3880, and other professional models; Canon PIXMA Pro9500 Mark II and imagePrograf series; HP Z3200 models, etc.

A suitable colorimeter or spectrophotometer, such as: Datacolor Spyder3Print, X-Rite ColorMunki, X-Rite i1, etc. This device will be used to evaluate the output of your printer by measuring a calibration target.

QuadToneRIP (QTR) to build the profile. This is an inexpensive ($50—shareware) software package dedicated to black and white output on inkjet printers. It includes a simple utility for creating B&W profiles that works even if your printer is not supported by QTR itself. In this guide, we'll be using this utility to create our ICC profile, but we won't use other QTR functionalities and will stick with the original printer driver for output.

Step by step instructions

Install QuadToneRIP.

Download the 21 step grayscale L* gamma target.

This target uses the QTR – Gray Lab color space, bundled with QuadToneRIP, which has a linear gamma response. This is my current workspace of choice for grayscale files. The linear gamma preserves shadow detail much better than a 2.2 gamma color space, like Gray Gamma 2.2, which I used previously. It is also impossible to obtain a perfectly linear curve when using a non-linear gamma, since, by function, gamma transformations compress tonal information in some parts of the scale. Read more about gamma correction here. (Thanks Mike King, on the QTR mailing list, for the tip.)

Print the target without color management and make sure to keep the original profile assigned when opening it.

If you’re using Adobe Photoshop CS5, this version doesn’t have the “No Color Management“ option on the print window. The workaround is to do a null profile transformation by outputting with the same profile as the image. In this case, in the print window select:

Color Handling: Photoshop Manages Colors
Printer Profile: QTR – Gray Lab
Rendering Intent: Relative colorimetric
Black Point Compensation: Off

Adobe provides a free utility for printing calibration targets, called Adobe Color Printer Utility. It bypasses the system color management to make sure it doesn't alter the printed target. Unfortunately it doesn’t support grayscale images, but works perfectly for color targets.

Make sure the target is printed with the same exact settings you'll be using later for your images and without any color management applied during output. Save these settings as a preset, so they're easy to remember later.

Let the print dry for a few hours to make sure it reaches color stability.

Measure each patch and export the values in the QTR format. I'll be using a Datacolor Spyder3Print in this guide. It provides an option to export directly in QTR measurement format and is the cheapest measuring device available. This procedure varies depending on the spectrophotometer you'll be using. You can also manually insert the measured LAB values in the QTR-21-gray.txt template file, located in the QuadToneRIP folder.

measuring-with-Spyder3Print.jpg

SpyderPrint can read and export targets directly into QTR format.

Save the measurements file with the name you'll be using for your ICC profile. Keep it simple and descriptive: you'll want to remember what paper and settings this profile is for.

Drag and drop the measurements file on the QTR-Create-ICC-RGB droplet, located in the QuadToneRIP folder. It'll generate two files: an output text file, with the measurement analysis results, and an .icc file, which is your actual ICC profile. The output file will show a crude graphical representation of your measurements. Notice that the luminance curve is not perfectly flat and linear, as we'd want. This means my printer was not perfectly linear. The A and B channels represent the slight color tones caused by paper color, black ink tone, and spectrophotometer accuracy, which is worse on the near black tones. This color cast is imperceptible.

qtr-out.png

QTR-Create-ICC output.

Why not use the QTR-Create-ICC droplet instead? Because grayscale ICC profiles are not supported by Lightroom. The RGB droplet creates a monochrome profile, but using a RGB color space, so Lightroom can load it. The end result is the same, but the RGB profile is more compatible. Depending on how you’ll be using the profiles, it might be useful to have both versions installed.

Copy the resulting profile to your system profiles folder.

MacOS
/Library/ColorSync/Profiles

Windows 7, Vista and XP
/Windows/system32/spool/drivers/color

Results

Note that the grayscale after profiling is more linear, almost a straight line. Besides soft proofing, which is handy, a linearized printer preserves better the subtle tonal separations throughout the scale. The end result is a slightly better and much more predictable print, even though the default driver output was pretty good, to begin with.

before-and-after-ICC-profile.png

Epson 3800 + Canson Baryta Photographique 310g/m2 - before and after profiling comparison.

Always use the “Dark“ tone setting when printing on the Advanced Black and White mode of an Epson printer. It’s the most linear of all presets. Make sure to check it before printing, since the “Darker“ setting is selected by default.

Measurement file format

If you're using a different measuring device that can't export directly on the QTR format, such as the Colormuki, use this file as a template and fill in the measurements manually. Each line contains: line number, patch percentage, Lab L value, Lab A value and Lab B value.

Read more: Which is the most linear Epson ABW mode?

Comments

chad
Nov 9th, 2011 - 21h58

I just picked up the R3000. I am going to give this "advanced B&W" setting a shot. I bought this printer hoping to make B&W printing simpler. Got my fingers crossed!!

Reply
Fabio
Nov 10th, 2011 - 10h18

Chad, this is a great printer and the advanced B&W mode gives excellent results without any tinkering. I'm sure you'll like it.

Keep in mind that the technique explained in this article is intended to get that extra percent of quality from the printer, but it isn't mandatory at all. Printing using the default advanced B&W settings and no output ICC profiles is fine for most users.

Thank you for your comment,

Reply
bill
Sep 4th, 2012 - 18h55

Hi Fabio,

How can this workflow be adapted to photoshop cs6? If one uses the ABW driver, there's no way to use a linearization file.

Reply
Fabio
Sep 20th, 2012 - 17h39

Hi, Bill.

The whole idea is to use QTR only to create the profile, but keep printing with the Epson ABW driver, which allows you to output from Photoshop or Lightroom using the profile on the print window. As long as you keep the printer driver configuration the same, the output will be linear, with the ICC profile compensating for the driver, paper and ink discrepancies.

Keep in mind that Lightroom requires RGB output profiles, so it's necessary to use the QTR-Create-ICC-RGB droplet to generate the profile.

Feel free to contact me if you have any questions.

Best,

Fabio

Reply
Franz
Nov 14th, 2012 - 04h16

Thanks for writing this. I've been reading a lot on this subject recently, and this is the best description I've seen, and the closest match to my needs. Questions:

1) I don't have PhotoShop, so I used Lightroom to print the gray scale, using "Profile: Managed by Printer". Do you think that'll work?

2) I measured the print using my Spyder3Print and created the profile using QTR as you describe, but when I use it in Lightroom 4 for soft proofing, it shows much of my image to be out of gamut. For example, if I soft proof the 21-step grayscale, it shows steps 9 through 20 as out of (destination) gamut. I'm wondering if that's caused by my measurements showing some color tint. Steps 9 - 20 all have LAB_B less than -2, but the others are all greater than -2. Maybe Lightroom is saying that it won't be able to print true neutrals of these values. Any thoughts?

Reply
Fabio
Nov 14th, 2012 - 18h19

Hello, Franz.

I think it's more straightforward to specify the color profile in Lightroom and disable color management on the printer driver. This would give you more control of the output and rendering intent and is less prone to user errors or incorrect driver configurations. I always take note of all driver settings used to create the profile, as it's very easy (for me) to forget them after a few days.

Regarding the out of gamut warning, I'm not encountering the same behavior with my profiles. The only case I've been able to find out of gamut colors on B&W images was when printing a very dark gray shade, almost black, on a lesser grade photo paper that had a low max density value and not-so-good shadow detail. In this case, Lightroom pointed correctly that the gray I was seeing on that image could not be reproduced by the printer, since it was so low that the printer clipped it to black.

Maybe the image you're using to test the gamut warning is not perfectly neutral and also not set in Black & White on Lightroom's develop module. I don't think the other way around (printer profile with some tint on the Lab A and B channels) would give you an out of gamut warning. But I may be wrong, since this is not something that I've tested extensively. Please report back with you findings when you track down the error.

I'll e-mail you a sample profile for you to test. Feel free to write me with any questions you may have.

Fabio

Reply
Franz
Nov 15th, 2012 - 01h57

Thanks for the reply (and the emailed samples). Two responses:

1) I'm not sure I understand you about how to print the grey scale. I thought the goal was to print it using my intended settings (Epson ABW mode in my case) *without* a profile. (And I've saved my settings as a preset so I don't forget them.)

2) I agree that it is hard to see how having a big LAB_B in the grey-scale measurements would produce a profile that causes out-of-gamut warnings, so I tried an experiment. I edited the measurements to set all the LAB_A and LAB_B to 0.0 and regenerated the profile. Now I don't get any out-of-gamut warnings, so that must be it. And, yes, my images are in Black & White mode.

Reply
Fabio
Nov 15th, 2012 - 10h23

Hello, Franz.

1) Sorry, I was thinking about the final images, not the target. Your settings are absolutely right, the target should always be printed without any color management and you should double check the driver settings to ensure color management is also disabled there.

2) Thank for reporting back. I didn't know this small and normal color cast could give out of gamut warnings. Living and learning.

Fabio

Reply
IDC
Apr 23rd, 2013 - 18h45

Hi Fabio,

I'd like to try your workflow but I have colormunki so I can't export directly in QTR measurement format. Can you show/explain to me how i can manually insert the measured LAB values in the QTR-21-gray.txt template file? Have you un example of an QTR-21-gray.txt filled? ths

Reply
Fabio
Apr 24th, 2013 - 14h35

Hello. You can use this file as a template for your measurements. Thank you for your comment.

Reply
Rusty
Jun 6th, 2013 - 13h57

THURSDAY JUNE 6, 2013 9:30 AM

I am in the Penticton Photography Club. We have an assignment for our next meeting and are to submit 5 B/W images to the club by email withing the next 3 days. I am 84 years old & am getting forgetful of all the things I have learned over the years with the many courses & seminars I have taken & attended. I have Adobe Photoshop Elements installed in my full sized Dell computer & Dell Laptop. I am thinking of having 'Lightroom' installed, however, you can't have both in the computers at the same time I understand. I would appreciated your comments about that I have a new 'Canon MX870 Printer that I am still in the process of learning about all the wonderful things it can do.

My question is....can I select 5 of my best coloured images that I already have and convert them to black & white images so I can submit them to the photo club for our assignment..... OR..Do I do I have to take my Canon G11 camera and reset the settings and then go out and take some new images?

I appreciate any advice you can give me about this photo project.

Bye for now,

RUSTY

Reply
Fabio
Jun 8th, 2013 - 10h54

Dear Rusty,

You can use either Photoshop Elements or Lightroom to convert your pictures to B&W. Both programs allow you to manipulate the conversion parameters, adjust the tone balance and contrast.

Lightroom combines image manipulation with cataloging and is, in my opinion, easier to use than Photoshop Elements. I'd suggest you to look into it for future projects. If you want a similar, more beginner friendly and free alternative, take a look at Google Picasa. It also combines cataloging and image manipulation on the same interface and works well.

After you convert your images to B&W for printing, make sure to select the grayscale or B&W mode of your printer on its driver settings page or printing dialog. Those modes combine the printer's basic colors in a way to avoid color casts and get the best B&W tonal response possible.

Thank you for your comment.

Fábio Pili

Reply
John O'Neill
Jun 25th, 2013 - 20h47

Dear Fabio

Thanks so much for your detailed article on this very interesting subject. Your explanation was concise and well written. May I ask what your your experience has been in getting a neutral output from ABW prior to making a linearisation profile? I have been tinkering around all week with colour tint settings and still haven't managed to produce an acceptable neutral print! I understand that K3 Black inks are very warm and usually you need to add some colour inks to cool the carbon tones down a bit. Intested to hear what settings you arrived at or did you get a neutral using the unadjusted settings with Manufacturers own brand paper?

Kindest regards

John

www.johnanthonyoneill.com

Reply
Fabio
Jun 26th, 2013 - 10h08

John,

I'm using Epson K3 inks on Canson Infinity Baryta Photographique and Rag Photographique papers. As you found out, ABW prints have a warm tint to them. Linearizing the output doesn't change this characteristic. I like the overall tone with those papers. It's a hint warm, but not overly warm like you describe. What papers have your tried?

Keep in mind that pigment prints also exhibit metamerism, which is a color cast caused by the illumination color temperature. If you are visualizing your print in warm light, like incandescent bulbs, it'll look much warmer than it really is. This phenomenon is less noticeable with K3 inks. In any case, it is important to evaluate the prints in color correct light, like Solux lamps.

As for adjusting the prints to the viewing conditions, your best bet is to use the "Color toning" controls in the Advanced Color Settings of the printer driver. An alternative would be to print using the color mode and create a custom color profile for it, but I wouldn't recommend it. The ABW mode uses mainly the neutral inks and will always be more neutral and with better max density than the color mode, for B&&W images.

Thank you for your comment,

Fabio

Reply
tonefoto
Jan 25th, 2014 - 19h30

Fabio,

I'm using a Mac Pro OS 10.6.8 with ABW and CS5 PS. The ABW is only accessible with Printer Manages Color which prohibits using icc profiles. My question is; does your workflow exclude MAC users in light of the new driver rules forced by the current OS in Mac?

Reply

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