Thursday, April 29, 2010

Color Calibration is the Key to Consistency; the substance of things hoped for and the evidence of things seen!

Talk to ten people about color management and you will get ten (or more) different answers. I really like the commentary that Frank Romano wrote for

Frank suggested that "color management is the ultimate oxymoron. You can no more manage color than you can manage light or nature (or even teenagers)."

Unclutter your mind, Standardize your equipment

We all know that the same color image looks different when viewed on different monitors, printed on different proofers and printers, on different brands of paper, or even viewed under different lighting environments. Yet this is the task that we are given to accomplish. Color management is about characterizing color imaging devices. It is about understanding color space and the creation and proper use of profiles, both input and output. Color management is about achieving color portability and predictability so that you can count on the result.

If you are working in the digital world, you have to manage color somehow, whether by eye or by making a substantial commitment to hardware, software and training. Regardless of how far you have traveled down the color management path, you know this isn't easy. Don't forget, every color device and every combination of ink and paper has its own color "signature" requiring separate profiling and calibration to achieve the best results. (Perhaps this is why my hair has gone gray way before it's time.)

While many of the people selling color management solutions would like you to believe that installing their group of widgets and software will give you perfect color all the time, I prefer to look at color management as a way to achieve repeatable, consistent results. No matter what you have done to set up your color managed workflow, there will be some colors that you just can't reproduce or that are out of gamut for your suite of devices. A good color management system will allow you to deal with this in an efficient manner. So consistency is the key to the overall success. So how do we arrive at consistency you ask? Good process control!

Getting to Consistency

How sophisticated do you need your color management system have to be?

If you are working on in-house newsletters or printing real estate flyers on a color laser or inkjet printer, you may not need to do anything more than calibrate your monitor. Working with the default settings on your digital camera, scanner and printer may be producing acceptable results as is. There are many ways to set up your color managed workflow, there are a lot of options none of them are 100% right or wrong. There ARE things though you should do and things you shouldn't do; but you have a lot of options.

One thing that is very important regardless of which color space you work in or what or what color output profiles you assign is you do have to use the SAME settings across all of your cameras, scanners, and software applications etc to maintain consistent results. If you have multiple designers or pre press people that have their own computers you have to ensure that both are working in the same color space and using the exact same settings or jobs coming from both of them will ALWAYS look different.

If you are working in a photography/design studio and someone else has to output the files you may want to see what they are using and how much sense it makes to adopt their system for consistency sake (always ask for some help from your printer). I have found most printers are pretty happy to explain how they like their files set up before they start on the job. This will usually go a long way when it gets to press time. They may even have custom profiles for the equipment you are using, making the process even easier. If you know who will do the final output you can call ahead to find out what they will run the job on and ask them if they have the output profile for their device or how they would like the file setup and delivered.

Printers have a hard time of it as they deal with so many clients that it many times is impossible to "train" all of their parters to provide them with exactly what they need in the format that they need it. Hence the Pre Press department earns their keep. There are a lot of things that must be done by printers to ensure consistent color job to job so that the Pressman do not have to be "Artists." Web submission has helped this by taking files and processing them in a consistent and predictable manner you know that the fonts and graphics are there as the customer submitted them.

Many times printers are using a particular standard like SWOP or GRACol or using a particular methodology like G7. Most of the time they will be more than happy to put their geeks with your geeks to save them time in the long run. Everything you do will get closer to what you are aiming for and over time you can perfect the "art" of color managing your systems to work with theirs.

If it exists, It exists to be Calibrated

If you are going to implement a color management strategy in your print center and start down this many times slippery path, you need to manage it all. Calibration is a way to ensure process control. Calibration is not color management but you cannot color manage what is not controlled! But it will help allow you to implement a system of color management that will ensure consistent, predictable and repeatable results. Color calibration is a requirement for all devices taking an active part of a color managed workflow. You cannot arbitrarily pick one element to "Control." For instance calibrating your monitor is not enough. You will need to calibrate and profile all of your monitors, or have just one dedicated color workstation that everyone works from. All devices that are part of the system need to be controlled! Maintaining process control will allow you to implement a successful color management program.

Consistency is one of the major keys to color accuracy; so whenever you can standardize equipment do so – that will make your job a lot easier. You will need to profile every combination of printer and substrates (paper) that you use, because of the differences between them. This is work but once you get started things get a lot easier and when you quit having to redo things to get colors right you will be thankful. First, you must calibrate your monitor – using your flavor of color calibration software along with a spectrophotometer that you will attach to your screen.

For the most accurate results you will want to have your monitors in a subdued light environment to be able to discern color. The walls of the room should be a neutral grey so they do not add ambient color to the images you are viewing.

The light recommended for the ultimate viewing your prints in production uses yet another standard called Kelvin. Daylight is considered to be 5000K or 5000 Kelvin.

You will want to look at the papers you use and standardize a bit. Pick a good smooth proofing sheet that you can always use to look at comps etc. This day and age it is hard to find a good digital sheet that isn't completely saturated in optical brighteners which give the sheet a slightly bluish hue.

Optical brighteners are additives that paper manufacturers put into paper in order to help a paper look "whiter." They do this to compensate for the yellowish or brownish tinges of the low quality paper. It is an optical illusion though and is to fool your eye into thinking the paper is a bright white. This many times is factored in with the "Brightness Factor" you see mentioned on the package numbers over 100 indicate a high level of optical brighteners have been used.

L* is also another term used for the quality of a sheet and refers to it's "Lightness". L is one of the components of the L*A*B* or CIE (Commission Internationale De l'Eclairage ) LAB color space. Paper has a profound effect on the ultimate appearance of the image as a sheet with an L* of 80 will be several shades darker than a paper with an L* of 90 and so on. This make makes a huge difference when printing on such papers, as the sheet with an L* of 80 will add a 22.75% K component to the image your printing where as an L* of 92 only adds 9.41%.

Moral of the story, pick a good sheet that you like it should have a brightness of at least 98 (only adds 2.35%) to minimize the effect of the added K and profile the paper; many times you do not have to re-profile do to adjustments in thickness but you do for finish changes like from matt to satin, to gloss to uncoated. Uncoated papers have a different gamut that they can produce do to the propensity of the toners, dry inks, offset inks and other pigments to absorb into the paper fibers and not lay on top like a well coated stock.

The next step in process control after you have done your monitors is to calibrate your printer(s). Most of the higher end systems with print controllers will have their own targets and process to accomplish this but there are many that can be used as a standard like the IT-8.7 target. Then you can move on to whatever input devices you use, i.e. scanners, digital cameras, etc. Once your input devices are calibrated, you have a closed loop, calibrated system that should make it easy to achieve files and prints with outstanding color fidelity. Many times your equipment vendor will have a couple great targets to use and can show you what they should look like considering your setup.

Printers like other equipment need to be continually calibrated to be brought back to a baseline. Characterization profiles (output profiles) can be used to maximize what is known about your particular system. As you change key components of your printer like replace ink, toner, drums, or any other color critical component you need to recalibrate. As things like corona wires get older they take charge differently and this will change your color if you do not calibrate your machine routinely. After long runs you may want to recalibrate as well. Whether it is daily, weekly or whatever you need to put a process in place to ensure it gets done and in the same fashion each time.

Easier said than Done

The sad thing is that it is all easier said than done, as Frank Romano put it, "There are many standards committees, organizations, and vendors working on "standardized" approaches to color reproduction. It seems that the more standards we have, the more chaos there is." For the most part this is true but if we do nothing at all we will have customers upset and operators that have no hair! We have to start somewhere. Your equipment vendors will have ideas that will guide you in the right direction in the end you will have to put together a system that makes sense for you. There is no end to color management so it can get involved. You need to work out a process that is duplicate-able and predictable. Keeping things simple enough that everyone can follow the process and use the system will greatly help your success. Human error can also lead to color infidelity so having a system that is understood and always followed is key!

Even when you apply science to every input, viewing, and output device we still cannot control how the client or end user will see the finished product under what lighting conditions etc. The reality is that color management albeit full of science is still a highly practiced art form.

Bon Appetite

Pirate Mike


  1. Thanks for sharing, I will bookmark and be back again

  2. Wonderful blog & good post.Its really helpful for me, awaiting for more new post. Keep Blogging!