VDIS10021 Working in Digital Design - Lecture 4 - Digital Colour Management
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VDIS10021 Working in Digital Design - Lecture 4 - Digital Colour Management

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This lecture is an overview that defines what digital colour is and how it can be managed through appropriate workflow to result in consistent colour outcomes for either web or print.

This lecture is an overview that defines what digital colour is and how it can be managed through appropriate workflow to result in consistent colour outcomes for either web or print.

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  • 1. Lecturer: Rachel Hawkins VIRTU DESIGN INSTITUTE WORKING IN DIGITAL DESIGN VDIS10021 DIGITAL COLOUR MANAGEMENT
  • 2. VIRTU DESIGN INSTITUTE: WORKING IN DIGITAL DESIGN - VDIS10021 2 What is Digital Colour Digital Colour is usually referred to as a Colour Space, Colour Model or Colour System. A Colour space is an abstract mathematical model which simply describes the range of colors as tuples (a data structure consisting of multiple parts) of numbers, typically as 3 or 4 values or colour components (e.g. RGB, CMYK, LAB). Simply speaking, colour space is an elaboration of the coordinate system. The majority of monitors adopt RGB color space because it is a convenient color model for computer graphics and the human visual system works in a similar way. This includes monitors on computors, smart phones, cameras and other similar devices. The most popular RGB color spaces are sRGB and Adobe RGB. An RGB monitor synthesizes colors additively by selectively illuminating each of its pixel’s red, green, and blue phosphor dots at varying levels of intensity. The light from a pixel’s three phosphor dots blends together to synthesize a single colour. In additive colour synthesis, all hues of the visible spectrum of light are mixtures of various proportions of one, two, or three of the primary colours of light. COLOUR SPACE Available colour systems are dependent on the medium with which a designer is working. When painting, an artist has a variety of paints to choose from, and mixed colours are achieved through the subtractive colour method. When a designer is utilizing the computer to generate digital media, colours are achieved with the additive colour method. Subtractive Colour - When we mix colours using paint, or through the printing process, we are using the subtractive colour method. Subtractive colour mixing means that one begins with white and ends with black; as one adds colour, the result gets darker and tends to black. CMYK is a subtractive colour system. The CMYK colour system is the colour system used for printing. ( Cyan, Magenta, Yellow, Black) Additive Colour - If we are working on a computer, the colours we see on the screen are created with light using the additive colour method. Additive colour mixing begins with black and ends with white; as more colour is added, the result is lighter and turns to white. RGB is an additive colour system. The RGB colours are light primaries and colours are created with light. Percentages of red, green, http://en.wikipedia.org/wiki/Color_space http://www.worqx.com/colour/color_systems.htm
  • 3. VIRTU DESIGN INSTITUTE: WORKING IN DIGITAL DESIGN - VDIS10021 3 Conversion/Colour translation Colour space conversion is the translation of the representation of a colour from one basis to another. This typically occurs in the context of converting an image that is represented in one colour space to another colour space, the goal being to make the translated image look as similar as possible to the original. Working With Systems The Visible spectrum consists of billions of colours, a monitor can display millions, a high quality printer is only capable of producing thousands, and older computer systems may be limited to 216 cross-platform colours. Reproducing colour can be problematic with regard to printed, digital media, because what we see is not what is possible to get. Although a monitor may be able to display ‘true colour’ (16,000,000 colours), millions of these colours are outside of the spectrum available to printers. Since digital designs are generated using the RGB colour system, colours used in those designs must be part of the CMYK spectrum or they will not be reproduced with proper colour rendering. Working within the CMYK colour system, or choosing colours from Pantone© palettes insures proper colour rendering. Indexed colour Indexed colour is a technique to manage digital images’ colours in a limited fashion, in order to save computer memory and file storage, while speeding up display refresh and file transfers. It is a form of vector quantization compression. This images is a 256 colours. CIELAB and CIE XYZ CIELAB and CIE XYZ are similar colour models designed to approximate human vision. Because these colour models include so many colours, they are both used when translating from one colour model, such as RGB, to another, such as CMYK. These are referred to as profile connection spaces (PCS). For instance, Photoshop uses CIELAB as a reference colour space when it converts from one RGB profile to another RGB colour space. Photoshop uses CIE XYZ when it converts from the RGB colour mode to the CMYK colour mode. It’s possible to use the CIELAB colour space for image editing in Photoshop, although few choose it for that purpose since it is not as easy to understand as the other colour models. http://en.wikipedia.org/wiki/Color_space http://www.worqx.com/colour/color_systems.htm L*a*b* colour uses three channels to represent the theoretical range of human vision: Lightness (L*), and two colour channels of opposing values of red-green (a*) and yellow-blue (b*). L*a*b* colour is different to RGB and CMYK in that it is both a colour model and a colour space. It is also a device- independent colour space, meaning that its colour values are absolute and not tied to any particular piece of hardware. http://dpbestflow.org/colour/color-space-and-color-profiles
  • 4. VIRTU DESIGN INSTITUTE: WORKING IN DIGITAL DESIGN - VDIS10021 4 What is Colour Management? Colour Management is the process of tuning your cameras, scanners, computers, monitors, software and printers into a universal standard for colour so that you can ensure accuracy when reproducing images. Color management is not about making photos look better or getting the best color out of a particular device. Color management aligns an entire system of cameras, displays and printers so that the different color spaces (colors) produced are as close as possible. For example, factors such as the color of printing paper, the lighting in the room and lighting in the original photo can all affect the way colors appear. Color Management – is a way to set up your environment and process (called a workflow) to allow all these devices to speak the same language so you can get accurate and predictable results. The ultimate goal is to match the colors of the image displayed on your monitor with the ones produced by your printer. Why colour manage? Good colour management will improve the accuracy of colour reproduction between digital input, monitor and digital output. Monitors and printers all have their own colour idiosyncrasies and it is impossible to make them a perfect match. It is however possible to convert the color data of each device via a common color space so that the various colours can match more closely. This is the basic principle of color management. The fact is all your devices – scanners, digital cameras, monitors, and printers – reproduce colors differently. There are even differences in the way individual printers of the same model manage color. Many variables affect color, including your ink and paper type. What is involved in colour management? Using special hardware and software you can program your digital devices to perform to standards that you determine. This process is the creation of ‘Profiles’. The resulting profiles are then slotted into your studios’ workflow. Once you have installed a profile you can then determine the devices performance based on that profile. Color management can be performed by following a set of rules to correctly handle the data. Color management will not only improve the end quality but also bring other major benefits to each work step. In addition to colour profiles you need to calibrate your devices so the colour display is as consistent as possible across all of them. http://suitecreative.com/studio-services/colour-management/
  • 5. VIRTU DESIGN INSTITUTE: WORKING IN DIGITAL DESIGN - VDIS10021 5 Simply, color management provides a unified environment for handling colors where a common color reference is used at each step of production, from photography to design, plate making, and printing. From the Eizo Color Management Handbook
  • 6. VIRTU DESIGN INSTITUTE: WORKING IN DIGITAL DESIGN - VDIS10021 6 Colour management fundamentals Putting in place a good colour workflow ensures the best possible results for your digital images. Colour workflow is required regardless of if the images will end up in print or on the web. Consistent and accurate results save both time and money for you and your clients. There are three fundermental stages in colour management: If we focus in on each of these areas there are several steps that can be taken to ensure the workflow addresses all colour influences in the journey between input and output. Step 1: Light Sources - The colour of an image at the capture stage is heavily influenced by the environmental light sources like the sun, light bulbs or a camera flash. Being aware of these influences and controlling them will improve colour results for input. Step 2: Input - Capturing and image through a camera or scanner can be influenced by the type of lens and scanner type. Creating a device specific colour profile will mean that you can predict what colour will be captured by the device. Step 3: Profiling - Most digital devices have ‘dependent colour systems’. This means that each devices colour differs depending on the settings of that device. It is therefore important to profile each device and install the profiles to result in device independent colour with consistency across the board. Step 4: Process - Once your monitor has been profiled you can start optimizing your images. You will need to consider the ambient light in your environment and how that effects the way you view the colour on your screen. Step 5: Output - Again you will need to profile your printer so that it works in-line with your other devices. Printers use a different colour space than your screen process so there will be a conversion of colour spaces. The colour on your print should match your screen colour and intensity. If using a commercial printer consult them on colour management and request a printed proof. The printing substrate will also affect the colour. Gloss, matt, coated and recycled papers all absorb inks/toners differently which alters the appearance of colour. Lastly, for web images consider that viewing colour on your smartphone and in different browsers may affect the colour output.
  • 7. VIRTU DESIGN INSTITUTE: WORKING IN DIGITAL DESIGN - VDIS10021 7 Watch this online tutorial on Colour Management EP09: Colour Management - Back to Basics by Learning DSLR www.youtube.com/embed/gILWsnHupdE
  • 8. VIRTU DESIGN INSTITUTE: WORKING IN DIGITAL DESIGN - VDIS10021 8 What is a Colour Profile A color profile is a numerical model of a color space. Operating systems and programs need to have access to a profile that describes the meaning of the color values in order to interpret the color correctly. Proper color management requires all image files to have an embedded profile. The International Color Consortium (ICC) has a set of standards that are attached to colour profiles to standardise colour use. There are two types of profiles: matrix-based and table-based. Matrix- based profiles use mathematical formulas to describe the three- dimensional color space. They can be relatively small. They are most appropriate for working spaces and for use as embedded profiles. Table-based profiles, as the name implies, use a large table of sample points – called a Look Up Table or LUT – to define the three- dimensional color space. These profiles are more customizable, and are therefore more useful when translating color information from one space to another, or in describing the color characteristics of a particular device. Because they rely on many data points, they are much larger. Device-dependent and device-independent color spaces Some color profiles are purely theoretical and describe a way to turn color into numbers. These are device independent. Some profiles are made to compensate for the color signature of a device like a printer or monitor. These are known as device-dependent color spaces. When profiling your devices - cameras, scanners and printers you will most commonly use device independent profiles. International Color Consortium (ICC) The purpose of the ICC is to promote the use and adoption of open, vendor-neutral, cross-platform color management systems. The ICC encourages vendors to support the ICC profile format and the workflows required to use ICC profiles. Read more about the ICC at: www.color.org With the exception of monitor profiles, all profiles need to be applied to images using a color managed application. Profiles are applied in graphics and imaging applications that are ICC compliant, such as Adobe Photoshop, QuarkXPress, Adobe Illustrator and Corel. COMMONLY USED PROFILES: • Adobe RGB (1998) • US Web Coated (SWOP) v2 • sRGB • Coated FOGRA27 (ISO 12647-2:2004) • ColorMatch RGB • Coated FOGRA39 (ISO 12647-2:2004) • CIELAB (L*a*b*) or CIEXYZ • Japan Color 2001 Coated EXAMPLES OF ICC STANDARDS: • ISO/IEC 10918-1: Coding of still pictures - JPEG • ISO 12639:2004 Graphic technology — Prepress digital data exchange — Tagged Image File Format for Image Technology (TIFF/IT) (ISO TC130) • ISO/DIS 12647-1: Graphic Technology - Process control for the production of halftone color separations, proof and production prints – part 1: Parameters and measurement methods (Revision under way in ISO TC130) • ISO/IEC 15948: Portable Network Graphics file format (jointly defined with W3C – see www.libpng.org/pub/png/spec/iso) • ISO/IEC15444: Coding of still pictures - JPEG2000 (ISO JTC 1/SC 2) • ISO 22028-1:2004 Photography and Graphic Technology – Extended color encodings for digital image storage, manipulation and interchange – Part 1: Architecture and requirements (ISO TC42) • ISO 12052 / NEMA PS3 Digital Imaging and Communications in Medicine (DICOM)
  • 9. VIRTU DESIGN INSTITUTE: WORKING IN DIGITAL DESIGN - VDIS10021 9 Setting up profiles in Photoshop In order to get Photoshop to colour manage optimally, you’ll want to check a few options that are part of the Colour Settings dialogue (available in the Edit menu.) A good setup is shown below. FIGURE 5 Make sure to set Photoshop’s colour settings to warn you whenever a profile is missing. If you work mostly in 8 bit, set your RGB space to Adobe RGB. If you often work in 16 bit, you may want to choose ProPhoto RGB. HOW DOES THE PROFILE GET THERE? Profiles are created and attached to files in a number of ways: When a JPEG file is created in a digital camera, a profile is usually attached to it. Many cameras give you a choice between sRGB and Adobe RGB. When a raw file is created in a digital camera, it has no inherent profile. The profile gets applied to the raw file as it is opened by a raw converter into a rendered file type, such as TIFF, JPEG or PSD. Scanners have the option of attaching a profile when the image is scanned. Do so. If you create a brand new file in Photoshop, it will be created in the working space that is specified in the Photoshop Colour Settings, shown below. Make sure the Embed Profile checkbox is selected in the Save dialog. When a file with no embedded profile is opened in Photoshop, you should determine the “best” profile to use then embed that profile when you close the file. FIGURE 3 When you save a file in Photoshop, you should always embed the profile so the next time a program opens it, the colour can be rendered correctly. http://dpbestflow.org/colour/color-space-and-color-profiles
  • 10. VIRTU DESIGN INSTITUTE: WORKING IN DIGITAL DESIGN - VDIS10021 10 WHAT DO I DO IF THERE’S NO PROFILE? If an image has no profile, and you have Photoshop set up correctly, you should get a warning that looks like that in Figure 4. • You can assign various profiles, and see the effect on the image. • You should NOT choose “Don’t Colour Manage”. That command should really be named “Colour Manage Incorrectly”. • Make sure you embed the profile when you save this file so that it will be colour managed in the future. FIGURE 4 If an image does not have a profile, you should assign one when it gets opened in Photoshop. Open the file, with a profile – sRGB is a good guess. If it does not look right, then try other profiles until you find the best match. ASSIGNING PROFILES TO UNPROFILED IMAGE If your image does not have an embedded profile, you will need to assign one on the way in to Photoshop. You’ll need to experiment with various profiles until you find one that makes the image look its best. As a general rule of thumb, most RGB images that don’t have an embedded profile look best when assigned an sRGB profile. Many digital point-and-shoot cameras capture images in sRGB colour space but don’t automatically embed the profile in the image file. Once you have assigned a profile and saved the image file with the profile embedded, the image file can be colour managed. What this video to understand the process. http://vimeo.com/7539576 HOW DO I KNOW WHAT PROFILE IS ATTACHED TO THE IMAGE? An easy way to determine the profile of an image is to open it in Photoshop and view the information at the bottom left of the Photoshop window as shown in Figure 5. If an image doesn’t have an embedded profile, this will report that the image is untagged. FIGURE 5 The readout at the bottom of the Photoshop window shows you several kinds of information, including the colour profile. If it’s not showing, click the triangle flyout menu then choose Show>Document Profile. http://dpbestflow.org/colour/color-management-overview#cmyk
  • 11. VIRTU DESIGN INSTITUTE: WORKING IN DIGITAL DESIGN - VDIS10021 11 HOW TO CALIBRATE YOUR MONITOR FOR THE BEST VIEWING EXPERIENCE POSSIBLE By Brandon Widder - May 19, 2014 Read more: http://www.digitaltrends.com/computing/how-to-calibrate-your-monitor/#ixzz37nFEeGgC Regardless of if you’re a graphic designer, a digital photographer, or just your Average Joe, image quality and accuracy are always important. Proper monitor calibration will ensure that your colours and black levels are true, and will ensure that your monitor is producing the best results for editing and viewing images and videos. Plus, it’ll be easier on your eyes! You could take your monitor to a professional to have it done, but why not do it yourself and save the money? The standard calibration process is relatively quick, hassle-free, and will help guarantee you’re viewing content the way it is meant to be seen. Here’s our guide to calibrating your monitor to help make sure colours are represented accurately at all times. We can’t guarantee you will produce results as good as the pros, but even these basic calibration procedures will help outshine your monitor’s factory presets. Before you begin You’re going to want to do several things before you begin the calibration process. Turn on your monitor at least a half hour before calibration so the monitor can warm up to its normal operating temperature and conditions. Set your monitor’s resolution to its native, default screen resolution. Make sure your calibrating in a room with moderate ambient lighting. The room doesn’t need to be pitch black, but you don’t want the sharp glares and colour casts resulting from direct light. Familiarize yourself with your monitor’s display controls. They may be located on the monitor itself, on the keyboard, or within the operating system control panel. Calibrate using built-in utilities Both Mac OS X and Windows have built-in display calibration tools to help guide you through the process, step-by-step, if you are new to the calibration process. The free tools should be the first stop if you’re merely a casual image junkie or working on a tight budget. They are extremely handy, quick, and easy to locate on your operating system. Keep in mind the adjustments will be limited by the display type and model. The assorted terms (i.e. gamma, white point, etc.) may seem a bit daunting at first glance, but each utility provides a relatively simple explanation of what they all mean. Realistically though, you don’t need to know the ins-and-outs of the jargon in order to calibrate your monitor. Windows In Windows, the display calibration tool is located in the Display Control Panel (found under “Appearance” in most versions of the OS). If you are having trouble finding it, try entering “calibrate” in the search bar to scan through your computer’s various folders and files. The results should show an option to calibrate your computer’s monitor. Click it. Window’s thorough instructions will walk you through the calibration process once you’ve found and opened the software utility. Just follow the on-screen instructions to choose your display’s gamma, brightness, contrast, and colour balance settings. A sample image for you to match will accompany many of the settings. Simply make adjustments to mimic the sample as close as possible. Once the calibration wizard is complete, make sure to choose the “current calibration,” or return to the previous calibration if you are unsatisfied with the results.
  • 12. VIRTU DESIGN INSTITUTE: WORKING IN DIGITAL DESIGN - VDIS10021 12 Mac OS X In Mac OS X, the Display Calibrator Assistant is located in the system preferences under the “Displays” tab. If you are having trouble finding it, try entering “calibrate” in Spotlight to scan through your computer’s various folders and files. The result should show an option to open the utility in the system preferences panel. Mac’s step-by-step instructions will walk you through the calibration process once you’ve found and opened the software utility. Just follow the on-screen instructions to choose your display’s brightness, contrast, native gamma, target gamma, and target white point. Click “Continue” and save the calibration profile once you finish with all of the adjustments. Calibrate using Web software There are a handful of Web-based calibration tools that help you manually adjust your monitor settings, essentially ditching the automation in favor of a bit more customization and control. Display Calibration: Display Calibration will let you view several test patterns and samples of what a properly calibrated screen will look like. Although the site isn’t the most aesthetically pleasing, and it’s rarely updated, the on-screen calibration tools for brightness, contrast, colour depth, and screen resolution can prove useful if you can’t access any built-in calibration tools. Photo Friday: Photo Friday is a simple webpage to help you calibrate the brightness and contrast of your screen. Just adjust the monitor settings until the transition of tones from black to white are clearly distinguishable on the screen. Online Monitor Test: Online Monitor Test is one of the better calibration websites out there. There are a slew of interactive tests to help you adjust your monitor’s screen colours and to see if your monitor can produce smooth gradients. There are also tools for pinpointing damaged pixels and backlight bleeding, making the website one of the more full-fledged Web-based calibration tools to date. The Logam LCD Monitor Test Pages: The Logam LCD Monitor Test Pages are handy, both online and offline. The website not only allows you to adjust various things such contrast and response time, but it also allows you to download the images as a 120KB zip file so you can check any monitor in-store that your are thinking about purchasing. Calibrate using calorimeter hardware The built-in calibration utilities and Web-based software are great for a quick fix, but they are inherently flawed by one thing – you. These calibration processes rely on an individual’s perception of colour, and are therefore open to subjectivity based on how you see different colours. Purchasing a calibrating device is one way to bypass this dilemma and better ensure your monitor is calibrated to its true potential. You will need to invest some serious money if you’re looking for greater precision and control, but there are still some affordable alternatives that work well on a tight budget and will help obtain colour consistency across all your monitors. If you’re looking to pick up a calibration tool, we recommend using the Spyder4Express ($120), the Spyder4Pro ($169), or the Spyder4Elite ($250). All three devices feature a full-spectrum seven-color sensor to help accurately characterize a variety of wide gamut and normal displays, but the more expensive versions are better equipped for the seasoned calibrator and are packed with more features. If you do decide to purchase one, all you have to do is attach the device to the screen, connect it to a USB port, and run the included calibration software. The automated software will walk you through the rest of the process.
  • 13. VIRTU DESIGN INSTITUTE: WORKING IN DIGITAL DESIGN - VDIS10021 13 X-Rite’s ColorMunki series ($100 to $500) is also a good alternative. Like the Spyder series, all three devices come bundled with automated calibration software with the more expensive versions touting more features and greater customization. The bottom line Calibrating your monitor is a simple task, and one that benefits you on many fronts. Aside from more accurate looking images and less strain on your eyes, calibrating your monitor will also help ensure your prints match your display. Plus, basic monitor calibration can be done completely free of charge or for a small fee should you decide you want a more professional setup. There’s no reason you have to stick with the settings your monitor came with. Read more: http://www.digitaltrends.com/computing/how-to-calibrate-your-monitor/2/#ixzz37sVkdzbS
  • 14. VIRTU DESIGN INSTITUTE: WORKING IN DIGITAL DESIGN - VDIS10021 14 Convert, Proof & Print CMYK CONVERSION BASICS When you convert to CMYK, it’s important to understand the following points and keep them in mind as you examine the conversion that you produce. • You are transforming between color models. • You will be mapping colors to a smaller gamut space. • Your goal is to preserve as much of the color appearance as possible in the transformation. • You have more tools to control the nature of the color conversion, such as different rendering intents, because RGB to CMYK conversions use the more sophisticated LUT based profiles. SOFTPROOFING WORKFLOW FOR CMYK CONVERSIONS Here’s a basic list of steps we recommend for the creation of a CMYK conversion. The movie will demonstrate each of these and show how using the options can help make a better final image. Additional information on using Photoshop tools to improve CMYK conversions can be found in Rick McCleary’s book or the Digital Photography Best Practices and Workflow Handbook. • Make a duplicate copy of your image file. This will serve as your RGB reference file. Arrange the reference file and the target file side-by-side on your monitor. • Select main file. Open Soft Proofing and select the destination space (the CMYK target space). • Confirm that the Black Point Compensation and Black Ink boxes are checked. • Toggle rendering intents to compare the reference file to see which produces the best conversion. • If problem areas show up in conversion, check the gamut warning. • If adjustment is needed, create an HSL adjustment layer called CMYK conversion. • First try to adjust Saturation for affected colors. • Adjust Hue if more work is necessary. • Once you are happy with the soft proofed target file, it is ready for conversion to CMYK. If you plan to deliver sized and sharpened CMYK, you’ll need to do the sharpening workflow step before actually converting to CMYK. Watch a video on this process at http://vimeo.com/7539338 SHARPENING FOR OUTPUT • If you know what size the image will be printed, resize the image before sharpening. • If you don’t know what the final size is, you’ll have to choose between sharpening generically or not sharpening, then clearly communicating to the image receiver that the file has not been sharpened. CMYK GUIDE PRINTS CMYK guide prints can be a very useful tool especially when the printer is unknown. These are easily produced on desktop printers. The main criteria is that you have a good profile for the printer/paper combination. You should also make the print from either the CMYK proof space (RGB file with the appropriate CMYK profile set as the destination space) or from the CMYK derivative file. Doing either will restrict the colors to the target CMYK color gamut which gives a realistic preview of how the image file will print on the offset press. Using the printer driver will give a good visual match; using a Raster Image Processor will get you even closer, especially if the RIP has a linearization function. Linearization calibrates the printer and makes the profile even more accurate. RIP-driven ink-jets are, in fact, what printers use nowadays for making proofs. DELIVERING CMYK FILES It is ideal to deliver CMYK files with their accompanying CMYK guide prints. However, electronic delivery of final files is becoming more and more common due to speed, convenience and cost considerations. For this reason, we recommend that you deliver CMYK files with an embedded CMYK profile. The printer may well convert your CMYK profile to his CMYK profile, or he may need to alter certain variables such as the total ink limits to match the paper. If he has a known starting point of an embedded profile, his job will be easier and your chances of seeing correct color will increase. For those photographers who are told to deliver RGB files only, one work-around is to actually convert to CMYK — allowing you to control the process and
  • 15. VIRTU DESIGN INSTITUTE: WORKING IN DIGITAL DESIGN - VDIS10021 15 color — and then convert back to RGB. When the printer gets those files and converts them to CMYK, you will have a better chance of having your images appear as intended. THE REST OF THE STORY Offset presses are different to other printing devices in that they have much greater calibration control at the point of printing. Newer presses are controlled by computers that can adjust the mix of inks at many points across the press sheet with a high degree of accuracy. Just as we gray-balance monitors and gray-balance cameras, good press operators gray-balance their presses. The gray-balancing methodology outlined in the GRACoL/ SWOP specifications has the huge benefit of making specific CMYK profiles largely irrelevant except in the unusual case of non-standard ink colors. Three profiles, one for sheetfed presses and two for web presses, cover the range of papers from premium coated #1 sheets to wood pulp based #5 sheets. Adobe’s version of these three profiles ships with CS4. Or if you prefer, the GRACoL/SWOP versions can be downloaded from the SWOP.org website. The GRACoL Coated profiles can be used in place of U.S. Sheetfed Coated and The Web Coated SWOP 2006 Grade 3 or Grade 5 paper profiles can replace the U.S. Web Coated v2 profiles that shipped with earlier versions of Photoshop up to CS3. We have discovered that even non color-managed print shops print better from the new GRACoL or SWOP profiles (as long as they don’t assign a different profile to the image files). If you are provided with a specific CMYK profile, by all means use it; however, don’t assume that just because the printer is unknown you are unable to deliver good CMYK files. An additional benefit of the GRACoL/SWOP methodology and the accompanying CMYK profiles is that they maximize the CMYK gamut, getting the most color out of the press and making conversion from RGB easier, since less color gets clipped. Although the new profiles are all formulated for coated stock and have correspondingly high Total Ink Limits, most printers can easily bring those values down for uncoated stock via Photoshop, a device link profile or by means of the RIP. Article from dpBestflow Commercial Printing written by Richard Anderson LAST UPDATED FEBRUARY 27, 2012 http://dpbestflow.org/node/268