I’m not quite sure how far back the discussion (aka argument) goes regarding gray bars and achieving gray balance on press through their use in newspapers. Many articles I have read go back well into the 1980s and I’m fairly sure the debate went on well before that.
I’ll start with the theory of gray balance. I’m not going to attempt to go into the techie aspects of things because, to be quite honest, there are numerous excellent articles on the theory of gray balance written by individuals much more qualified on the subject then myself. Instead, I’m going to look at things from a newspaper prospective and how gray bars affect our industry and their use and possible value.
If you’re not familiar with gray bars, here’s a brief summary of what they’re about.
Gray bars are a combination of three primary newspaper printing colors: cyan, magenta and yellow to achieve gray balance. The theory is that when you fingerprint your press and establish standard density in your process colors independently, you arrive at a measurable gray balance that can maintain standards for full color printing and ensure consistency. When set-up correctly and measurements are established and maintained with a densitometer, the bar will print as a neutral grey under normal printing conditions.
If the gray bar takes on any variation of color, i.e. a shift in color cast and appears bluish, greenish, reddish, etc. to the eye, you are “out of balance” in your process color settings and a correction is necessary to return to natural gray balance.
The benefit of a balanced gray bar is consistency in printing.
Gray balance that is tested and set-up meticulously on the front-end (prepress) then maintained throughout the printing process will give you this consistency. Ninety-nine percent of the time, if you are able to achieve gray balance on press, it will match the desired color proof and with a very small degree of tweaking on press will satisfy even the toughest critic (or commercial customer).
In effect, the gray bar acts as a guide or benchmark to set ink and takes that function away from the live image areas, such as photos.
Establishing a Proper Gray Balance
The first step to incorporating a gray scale (if you choose to use one after reading this entire article) is to run a very simple press test.
First, make sure that your press is printing optimally; i.e. roller settings in spec, blankets in spec, iron to iron set, good quality plates exposed properly, good chemistry, etc.
Anytime any of these change after the test, it will affect gray balance and consistency. Seeing these changes can be a blessing or a nightmare. Being able to recognize the changes as they occur can provide a great indicator/tool to let you know what is going wrong (once you’re able to analyze what each change means).
But, if you establish baseline measurements for your color bar/gray balance for the test and don’t maintain the basics I’ve listed here, you could end up chasing your tail to maintain gray balance and soon, colors in your image area will be adversely affected by the tail chasing process. In other words, once you’ve established a baseline for your gray bar, monitor those changes and fix the problem instead of adjusting to it.
The simplest test I’ve found is one you set up yourself. Throw a few nice color photos on a page with a cyan, magenta, yellow and black color bars running across the top, middle and bottom of the page, along with a bar composed of CMY screens at a percentage recommended by the vendor. A typical setting is 50 cyan, 40 magenta and 40 yellow. Work with your ink vendor to decide on proper density settings for your CMYK solids and have a well calibrated densitometer ready to measure all filter readings in the gray bar for CMYK. Warm up your press and take CMYK measurements across the page, and once you’re where you want to be (guided by the vendor), record the makeup (density readings) of the gray bar.
The final printed bar should be gray and ink set even across. It should appear a natural gray to the eye and measure accordingly. There should be no color cast measurable or visible throughout. Very slight density readings may be unavoidable across the bar but should be kept within tight/strict tolerances. It’s also important to make sure that you use the same dot size (screen) in your gray bar as you do your images/photos.
Once you have this guide, it will become the baseline for all your printing.
Are Gray Bars Still a Good Practice for Newspapers?
I see this as matter of opinion and personal preference. It’s hard to argue with the fact that you can establish consistency through the use of gray bars and that consistency in printing and ink savings can be achieved through their use. But are they practical for every application? I believe they are not.
The majority of the work done in large commercial shops involves long runs and the use of gray bars throughout the run is critical in maintaining uniformity and consistent color balance; this cannot be debated.
Additionally, any “tool” we can benefit from in printing is valuable. Gray bars fall into a category of being very beneficial for long runs, but I would argue their value on many of the short commercial runs most of us have in our shops.
Which brings us to our next question: Are memory colors sufficient for short runs, and should gray bars be eliminated in the interest of saving space?
What color is grass? What color is the sky? Basic flesh tones? Sidewalks/cement? A red brick? If a hue/cast appears in any of these memory colors, it will normally be immediately noticeable.
Let’s break these questions down briefly.
I’ve seen numerous photos in which grass has an extreme blue hue to it. Should the press operator be chastised for ignoring the gray bar balance and setting the ink properly to achieve green grass? I don’t believe so.
The sky is most of the time blue, of course. There are many different shades of blue—light red, gray in the sky of many photos, but for the most part, if you’re looking at a green sky something is drastically wrong with the photo. Should the press operator be chastised for ignoring the gray bar balance and setting the ink properly? Probably not.
The list goes on. Can these issues with a cast be controlled with a properly fingerprinted press and a test on the front-end (and on press) to establish densitometer measurements and achieve proper gray balance giving us more consistent printing? Absolutely.
But is that practical for the small runs that many of our shops have? Possibly not.
Another side of the argument is credit to gray bars for any size run. Besides the obvious benefit of a gray bar lending itself to print consistently, there is another side of things to consider.
Everyone—and I mean everyone—sees color a bit differently. How many times have you had a commercial customer or publisher complain about a color photo and you’re looking at it trying to figure out exactly what the heck they’re talking about? The way I see color and the way you may see color can be two extremes. While beauty is in the eye of the beholder, it’s our jobs to please the masses; this argument flies in the face of the concept of memory colors.
I have a story that many of you press operators will completely understand. If you’ve been in the newspaper business for any amount of time, you’ve no doubt run into one of these individuals and can relate to my story.
In a shop I worked at many years ago in Massachusetts, I had a press operator that regardless of the length (draw) of the run always stuck close to the densitometer. We had gray bars on our paper and every time you’d turn around, he would be taking a reading and making a correction. Without a doubt, he was the best color operator in the shop and set color very consistently.
One day, I asked his supervisor why he was the only one who really relied on the densitometer when most of the other operators set ink density to memory colors (I should have been able to figure things out for myself, but I was fairly new to the industry). The answer was because the gentleman was certifiably color blind. Of course I had to confirm it with a few of the other operators who pointed out I seemed to be the only idiot in the shop that didn’t already know this.
Although to this day I’ll still argue the value of gray bars on short runs, this sticks in my mind as a pretty strong argument for the “Do it by the book” folks.
Now, what about incorporating gray balance into mastheads and page design? Is this still a necessary practice?
Regardless of the length of the press run, many newspapers continue to print gray bars on section fronts and other pages throughout the paper to monitor and control color settings. This concept was popularized and continues to be used by USA Today and other major newspapers throughout the world. So what do they know that we don’t, or are the use of gray bars overrated and overused?
First of all, let’s talk about placement. Most, if not all, large commercial shops (Quad Graphics, for example) use color bars with gray bars to maintain print consistency on press. The typical position of these bars is often in the trim area and you may never see them by the time the product hits your shop in the form of a preprint. But when a booklet is printed the typical placement, it’s normally down the spine of the book to hide it from the area of general real estate.
Years ago in newspapers, we decided to incorporate gray bars into the overall page design. I remember selling this concept to an editor and publisher to improve the overall quality of our color photos. Graphic artists and page designers quickly embraced the concept and to this day, several newspapers incorporate gray bars into their section fronts. It’s become such a common sight on newspaper pages that I truly believe most editors and readers pay it no mind anymore. But, it can also take up valuable space on a page when publishers simply run a large gray bar across the bottom of the page. In fairness to the editors who hate the big gray line on their front page, I suggest checking in with your production guys to see if they even use it. This may be a very unpopular statement, but I’d venture to guess that more than half of the newspapers with a gray bar on section fronts never take the densitometer out of the case. So why waste the space? Unless it helps page design, don’t.
It’s Your Decision
Like many things in printing, there often isn’t a right answer. The only answer is often to “What works best for your particular property?”
I get to share my opinion because right now I’m the one with the keyboard in front of me, but you’re the one who has to ensure your shop is pumping out the best quality work possible in the quickest time with minimal wasted time and money.
The case for memory colors is strong for short runs that don’t allow press operators to take enough accurate densitometer readings in the gray bar throughout the run. Many runs of 1,000 or 2,000 papers are over by the time you can get the densitometer out of the case. Additionally, to get the density reading exactly where you want it, you’ll add to your waste as the press runs and you’re still taking readings.
For short runs on newsprint, I’m a firm believer in setting color by eye; memory colors and a good (not color blind) press operator are the best way to go.
On the other side of the discussion, there is just no arguing with the fact that gray bars help to establish and maintain consistency and are a wonderful tool for longer runs.
What’s best for your shop is a decision you have to make.
Jerry Simpkins has more than 30 years of experience in printing and operations in the newspaper industry. Contact him on LinkedIn.com or at [email protected].