In Living Colour

PlotterEven the lowest quality newsprint routinely contains colour today. But when your work goes through so many people and processes, how can you make sure it stays true to life? Drew Turney looks at the world of colour management.

Which device in your workflow is the most powerful for discerning colour? Some would guess it’s the monitor — the days of 640×480 displays with 256 colours are long behind us. Most base level consumer models are set to at least 1024×768 pixels by default today, giving us millions of possible combinations of colour to choose from.

Some would guess it’s the printing press. With far more individual ‘bits’ of colour in a given area, the possibility to produce finer combinations of inks allows for far more detail and a smaller order of magnitude between shades.

Good guesses, but both are wrong. With the ability to discern wavelengths of between about 380 and 750 nanometres, the human eye can see more colours than we can ever produce in the digital world. It’s hard to measure mathematically as the retina, lens and pupil use wavelengths and frequencies rather than pixels or dots per inch, but estimates by armchair biologists put the figure at around ten million.

So colour management is impossible because the ability of your own two eyes to spot a shift is incredibly precise. Colours change because they go between output devices that rely on different technologies from different manufacturers using media that weren’t necessarily designed to be compatible with each other.

Try a quick experiment. Create an RGB Photoshop document and fill it with a bright, luminous screen hue like #ff0000 (red) or #0000ff (blue), then print it to your office inkjet printer and notice how drab and muddy the result is. In this case, good colour management would be to avoid colours that don’t reproduce on paper, which can’t show luminescence like a monitor. In a general sense, it’s about managing the countless variations that can occur output between the concept and the final product.

Good practice

Your design is going to travel a lot further than just layout program to your office inkjet. Original images might start on a drum scanner or a digital camera with presets of its own, the artwork will be assembled in a page layout program and colours of images further enhanced or tinkered with in an image manipulation program.

It’ll all happen on your monitor and then go to the client or manager’s monitor for proofing. You’ll proof it to your in-house multifunction device using particular ink and stock, and so will everyone else who sees it. The pre-press bureau might output proofs from plate stage, then they’ll put it on the press on yet another kind of stock with different dot gain and reflective properties to office copy paper.

It’s a long trip through lots of foreign territory, and all the care in the world making sure it looks great on your own system might count for nothing once it leaves your hands. The answer is profiles — colour parameters that ensure colour integrity regardless of the device or software. Different devices use different colour spaces (a colour space is basically a set of benchmarks for the mathematical values that render certain colours, but if you can stomach the hard science, look up ‘color spaces’ on Wikipedia).

For example, we see the image on our monitor in the RGB colour space, each letter representing a mathematical value. Your client says they want the subheads throughout their document red. Which red do they mean — blood, a rose or a Coca Cola can?

Colour management is the practice of settling on the colour we define as ‘red’ for this particular job, then giving absolute values to the numbers in a RGB value based on it. The RGB values are then completely independent of any device (screen or printer) that might be used to display the colours represented.

The red they’re looking at probably won’t look the same on your system. If you have two monitors it’s possible it won’t even look the same on both. The red the client chose at the beginning will be what’s called ‘device dependant’ when it shows up on various monitors or from various desktop printers.

The profiles of colour management are small sets of mathematical data that define color spaces and try to make sure the red we began with looks correct on your LCD monitor, the client’s CRT dinosaur, the marketing chief’s colour laser and the offset press. The most common of them are ICC (International Colour Consortium) profiles, although each device on your desk will have its own too.

Across the board

Colour spaces and profiles would be all very interesting if you were a software engineer, but you want to spend your time on design, not mind-bending abstracts. How do you apply colour management in a practical sense?

Depending on the elements of the job you might be starting either with a dummy layout or an external image, anything from a logo drawn in a vector graphics application to a photo imported from a high-end scan or camera.

When you first create or import images, Photoshop will assign them a colour space. The two common ones are simple RGB and CMYK, which you can see beside the file name in the title bar. You can manually apply colour spaces from a whole bunch of them based on common presses or software systems such as those by Adobe or Apple.

When you bring content into a file from another file with a different colour space, that’s when you get those error messages asking you to assign a colour space or use a default. Setting colour spaces for images all sounds very impressive and in extreme cases can make life easier, but making manual adjustments to images at pre-press stage to match original specs is doing more or less the same thing.

Even more effective colour management is to assign colours before you even click a mouse, such as adhering to PMS colours set out in a style guide or choosing the most effective ones for your design. Then you can assure yourself and your client the colour will come out at the other end as it appears on your PMS swatches …to a point (which we’ll get to later when we talk about stock).

Your monitor is the first and in many ways the most important step. It’s where you’ll be doing all your layout and element manipulation, after all. Sometimes, a digital camera at a professional shoot will be attached to a computer system that gives the first glimpse of the images taken, and if it isn’t properly calibrated the results on screen won’t be true to life or match the final product.

Like everything, monitor calibration systems can vary in price and quality. At one end of the scale, you can print out a photo, hold it up next to your monitor and adjust the contrast and brightness. The web is awash with free and cheap calibration tools, but if you’re into high definition photography or video or have a rich client who insists on 100 percent accuracy, you’ll want to invest in a colorimeter.

For $150 or less you can get Pantone’s Huey system, a colorimeter that attaches to your screen and reads the ambient light in relation to a series of colour output tests and calibrates your monitor for the conditions you work in.

Another is the Spyder 3 Elite system from Datacolor, a total colour management system starting with a wizard that offers to calibrate a new monitor as soon as you attach it. A couple of selections and settings give you your monitor’s gamma and white point, and the Spyder colorimeter is ready to attach. Stick it to the screen with the suction pad, click next, and watch it render a series of colours and shades to take readings.

When it’s done, you have a profile you can name and save for later. The Spyder system is built more for photographers than layout artists — it gives you a gallery of proofs divided into characteristics like skin tones and highlight contrasts. Click to zoom in to a single image and then you can hit the ‘switch’ button to view it both before and after calibration.

Like most designers, you might have calibrated your monitor a couple of times, but here’s something that might surprise you; when you’re working in high end digital colour (for example in photography), it’s not a bad idea to recalibrate your monitor as often as fortnightly. While they don’t shift as much as CRT monitors used to, even LCD and plasma are subject to the forces of nature, and colour representation on screen can shift for all sorts of reasons.

Hot off the press

There are a couple of reasons a desktop inkjet or laser printer won’t be a good representation of the final image. One is because the process is a little deceptive. Even though small instant printers have CMYK inks, they actually print in RGB. To achieve true four colour process printing, a file needs to go through a RIP or raster image processor (see sidebar).

The other is that a printer is built specifically for the ink and paper the manufacturer specifies. Use anything else and you won’t get the same result. Of course it’s not a big deal when you’re printing in-house proofs to check placement rather than colour, but if you’re in an operation such as fashion where accurate colour is crucial, you’ll work closer to your bureau or printer than most.

Speaking of which, things at the printer have changed. Just like your design goes from multifunction device or scanner to InDesign or Quark Xpress, from your monitor to your inkjet to your client’s system and back again, it goes from one device to another at the printer.

A newly minted recipient of the ISO standard 12647 (Colour proficient printers), Scott Print of Western Australia recently released a statement describing the long process of calibrating their proofing equipment, platesetters and presses to the extent that they achieved colour integrity ‘in the high 90% range’.

The Perth-based printer, who says its facilities are so world class international observers and customers are often taken to tour its facilities, hit a milestone early this year with a 100 percent score. When even previous records set by their equipment — of up to 98 percent — made the differences indistinguishable to the human eye, it was quite an achievement.

So while the new ISO certification looks good for Scotts, what does it mean for you? Quite simply, if your profiles and the integrity of your colour management is intact when you hand the job off to the printer, you can be assured they’ll stay that way throughout the rest of the process, from pre-press to the day the courier delivers it.

Of course, there are things you can do to make things easier for your printer, and amazingly in this day and age, most of the problems they have is from designers submitting images in low res or RGB format — a fundamental mistake that still happens.

Get your printer in the picture early. Ask for their own colour profiles and load them into your page layout of colour management systems to maintain colour throughout the workflow. Make sure you understand the difference between coated and uncoated stock — even stock of a certain shade – and take note of how the same colour behaves differently on each.

The Adobe Factor

It’s been quite a few years since you collected up your layout, fonts and pictures with Hunt and Gather, copied them onto a zip disk and couriered it off to the printer.

Since the Acrobat PDF format took over, it’s made file provisioning simpler from both ends, not least because you provide one file, not dozens or hundreds. Pre-flighting and outputting your layout from InDesign or Illustrator to a high res PDF is a sixty second process these days, and it’s been the preferred format by printers for a long time.

The other advantage is because Adobe — through Bridge — maintains a colour space throughout a job, and every application you might use to work on content for the project adheres to the same standards and speaks the same language.

Don’t let that frighten you away from using any other page layout application though. There’s nothing stopping you from bringing the project into InDesign prior to final press check provided InDesign or Illustrator can read the format.

The big difference between the Adobe way and the traditional file management path is you no longer have to resave the layout as a postscript file or distil it as a PDF prior to output. Making a postscript file out of an image flattens it, and in this age of layout-level overprinting and transparencies, you want to maintain the properties of your effects as far into the workflow as you can. Adobe lets you do so right up o plate stage.

Of course, up till now you might have got by just making sure your images were CMYK and they looked okay on your monitor, confident you could tweak any issues in pre-press. And honestly speaking, it’s still enough for most design work. But the more devices and screen your work appears on — from mobiles to cinema projectors — the more important colour management will be.