Color Management:a guide

200028910-001 Birgid Allig

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Getty Images test image 2Defining the challenge 3RGB to CMYK 4What are ICC profiles? 5Color guide:Step 1: Calibrate your monitor 6Step 2: Using ICC profiles 7Step 3: Sizing and scaling images 8Step 4: Sharpening images 8Step 5: Color conversions 10Color glossary 12FAQs 15Online color resources 16

Contents

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Getty Images test imageThis was created to give users an opportunity to test their color management system. The theme of the image is communication, testing instrumentation and visual aids. Three models with varying skin tones were chosen and each item covers all the colormanagement essentials: highlights, midtones,

shadows, catchlights, neutral and vibrant colors. Equipment: Mamiya RZ, with Phase One H20 back(16 mega pixel). Lighting: strobe 5,000 Joule packthrough two heads plus two Bowens (1,000 Joule)monolights, all bounced off white surfaces placedsymmetrically on either side of camera.

gettyimages.com/color-resources

If you have been designing with digital images,here’s a scenario you may have encountered:leafing through an image resource book, you find an image with perfect colors for the design you’reworking on, so you purchase and download theimage, or purchase a CD-ROM that contains it. But when you view it on your monitor, the colorsdon’t match the image in the book at all. When youprint it the colors are not even close to the original. What went wrong? Why and where?

Designing with color isn’t an automatic ‘what-you-see-is-what-you-get’ proposition.

Reliable color reproduction requires knowledge,patience, a fair amount of experience and the right tools.

Color management systems (CMSs) attempt toaccount for the different color reproductioncapabilities of scanners, digital cameras, monitorsand printers—that is, all the devices in the chainfrom initial input to final output. CMSs do the bestthey can with all the variables present. However,colors—and their reproducible ranges—tend tochange between devices and environments.

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Defining the challenge200014056-005 S

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Color management is the ability to accuratelypredict and control color while on this device-to-device digital journey.

It isn’t an arcane science but anyone who’s dabbledin it knows that it isn’t exactly child’s play either.Neither is color management an exact science.

High-tech advances continue to shift more colorand production control away from service providersand into your hands. With this additional controlcomes more responsibility and the need to becomemore of a color expert. We can help you to do that.

This color guide will help you solve many of theproblems you’ll encounter on the path from RGB (the color space of your monitor) to CMYK (the color space of a four-color press).

RGB files contain more color data (larger gamut)than CMYK files, and they weigh less in Megabytes.This means the RGB file is bigger, better (can be re-purposed more accurately) and weighs less than itsCMYK counterpart.

Getty Images printing procedure

There is no CMYK data manipulation in our printedproducts. We use the same JPEG version of the filethat you would receive, then use profiles to convertto CMYK. Once this is done there is no alteration tothe CMYK data at all. What you see in ourmarketing material is a clean interpretation of theRGB file that has been converted specifically to thatparticular paper stock type and press condition.

RGB to CMYK

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200119063-002 Manfred R

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Profiles, simply put, are device characterizationscontaining every variable in the color-reproductionprocess. It is critical that the data they contain areup-to-date and accurate.

The ICC (International Color Consortium) is a groupof companies that have joined forces to create,promote and encourage the standardization andevolution of an open, vendor-neutral, cross-platformcolor management system (CMS). Since itsinception in 1993, the ICC has grown from eight toover 50 companies, including Apple, Adobe,Heidelberg, Sun Microsystems, and Sony. The ICC has developed standard profiles, or devicecharacterizations, that contain information about thecolor-reproduction capabilities of devices such asscanners, digital cameras, monitors and printers.

Working closely with your service provider is thebest way to take advantage of ICC profiles andestablish a reliable CMS.

The four places where profiles are needed

Source: This profile represents the gamut of theimage. It can be embedded in the image, chosen in the application, or it can be a standardized colorspace such as sRGB.

Monitor: You can use the profile supplied by yourmonitor’s manufacturer, or create one using acolorimeter or spectrophotometer.

Proofer: In most cases, profiles for color printerscan be obtained from the manufacturer (check theirwebsite) or built using a spectrophotometer andprofiling software.

Final output: Going to press is where the bigmoney is spent and where an accurate profile isvital. Work with your service provider to determinethe exact requirements for your project.

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What are ICC profiles?70007596 P

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Step 1: Calibrate your monitor

Before tackling the specifics of monitor calibration,let’s consider a few general points about color andcolor reproduction. To begin with, keep this crucialrule in mind: color perception is subjective, ie.everyone sees color somewhat differently. Color, it’salso worth noting, isn’t an object. It is a property oflight, an object’s reflection of a particular portion ofthe visible spectrum.

It is affected by the light in your surroundings,especially when perceived on the printed page. For example, when viewing printed materials under an artificial light source such as a fluorescentlight, which has a bluish tint, the materials willappear bluer.There are basically two kinds of color rendering or reproduction: additive (the process used bymonitors) and subtractive (the process used inprint). With additive color (RGB), red, green and blue lights from the monitor are added together invarying degrees to create other colors. With

subtractive color (CMYK), four colorants–cyan,magenta, yellow and black–that subtract, orabsorb, components of white light are mixed.Changing the amounts of colored lights (additive) or the amounts of the colorants (subtractive) givesus a wide range, or gamut, of colors. Monitors(RGB) can normally render millions of colors while printers (CMYK) can render thousands. Our images are provided in RGB to give you thewidest gamut.

Exact Science? think againAs we said, color matching during the reproductionprocess is not an exact science. Not only is colorperception subjective, but monitors, printers,lighting, print surfaces and other outside influencesconspire to make a perfect match elusive.Calibrating your monitor is the first step you cantake to improve print predictability.

Monitor calibrationReliable color reproduction is critical. We use thelatest scanners, software and color management

Color guide

BLUE

RED GREEN

CYAN(B+G)

MAGENTA(R+B)

WHITE(R+G+B)

YELLOW(R+G)

CYAN

MAGENTA YELLOW

GREEN(-B AND -R)

BLUE(-R AND -G)

BLACK(-RGB)

RED(-B AND -G)

RED GREEN

(R+G+B)

YELLOW(R+G)

CYAN

MAGENTA YELLOW

GREEN(-B AND -R)

BLUE(-R AND -G)

BLACK(-RGB)

RED(-B AND -G)

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tools to ensure that the images you get from us areof the highest quality possible and that you seewhat the photographer intended you to see. A properly calibrated monitor is a criticalcomponent in this procedure, so we re-calibrate our monitors weekly.

Our technicians use Barco Reference Calibratormonitors set at a color temperature of 6,500°K andbalanced to D65, 1.8 gamma. This createsrepeatable, consistent viewing conditions thatconform to established standards in the graphicsindustry. But even with the best viewing conditionspossible, a translation must be made between lighttransmitted through the tube and light reflected offthe printed page. Nevertheless, we’re able toaccurately predict our output. Like comparing animage in a lightbox to a printed sheet, this processimproves with training and practice.

We want you to experience image quality the waywe do. Calibrating your monitor is one of thequickest, easiest and most significant steps youcan take towards increasing your color-relatedproductivity and peace of mind.

Remember to download our source profile—‘TiffRGB’—from this website. It comes from Heidelbergand we have adopted it as our RGB working space.Later on in this booklet, we will explain how to placethe profile correctly.

Calibration and profile tipsHere are several ways (from good to best) tocalibrate your monitor and create a profile:

• Use the canned profiles that came with yourmonitor. A caveat: This isn’t the most reliable method,because monitors vary greatly in manufacturingand change with age.

• Use a system that mounts a colorimeter orspectrophotometer on your monitor. Thesedevices start at around few hundred dollars butcould save thousands of dollars on proofs.

Additional tips• Staring at a monitor for long periods fatigues your

eyes. Try blinking to reduce eyestrain.• Clean your monitor before calibrating it.• Let your monitor warm up for 15-30 minutes

before calibrating it.

• Re-calibrate your monitor regularly.• Stabilize your room lighting; keep your lighting as

subdued and consistent as possible.• Remove dimmers.• Use grid diffusers to keep fluorescent lighting

directed downward.• Keep your monitor away from windows, or block

the light when looking at critical color.• Use a monitor hood to keep stray reflections off

the glass.• When viewing imagery on screen, try to wear dark

clothing as this will help reduce reflection.

Step 2: Using ICC profiles

In most instances, you’ll need two profiles (sourceand output) for a color-matching session. Theseprofiles allow for the vital cross-platformcommunication of color information. In other words,using ICC profiles, machines of variousmanufacture, function and origin can speak thesame color language.

The ICC’s website (www.color.org) providesinformation about the group’s current efforts, alongwith current profile specifications. See ‘Canned vs.custom’ below for further profile sources.

Putting profiles to workWorking closely with your service provider remainsthe best way to take advantage of ICC profiles andestablish a reliable CMS. We’ve provided the meansto get more consistent quality from your monitor,but keep in mind that this is only part of theworkflow solution. In order to increase printpredictability, you’re also going to need either anoutput profile supplied by your printer or a cannedprofile that you’ve tested.

Canned vs. customAs noted in Step 1, a significant difference existsbetween canned and custom profiles. Customprofiles are more accurate because many devices,printers for example, will ship with a canned profilethat doesn’t accurately reflect the specific behaviorof the printer on your desk. The same goes formonitors and scanners.

Bottom line: canned profiles are better than nothing,but for accuracy’s sake, if you can use a customone, do so. You can obtain canned profiles frommany manufacturers of scanners, digital camerasand printers, and from service providers.

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There are additional locations on the web (see‘Online color resources’ at the end of this guide) thatprovide device profiles and are also excellentresources for color management information.

Step 3: Sizing and scaling images

Pixels, halftones and image qualityFor many, the relationship between pixels andhalftone dots is very confusing. Plenty ofcontroversy revolves around sizing and scalingimages and how different raster image processors(RIPs), which convert vector graphics (imagesconsidered as lines rather than pixels) or text intobitmapped images, work with different programs.

Depending on how you plan to use an image andhow demanding you are about image quality, sizingand scaling issues will vary in degree of importanceand in implementation. Occasionally results, evenwith careful planning and calculation, can besurprising and apparently defy reason. For example:our images are routinely sized and scaled up toappear on large billboards. They end up looking finein spite of calculations that tell you that thisshouldn’t be the case. This is partially because theviewing distance is normally around 100 yards.Raster devicesMonitors are commonly set at 72-75 pixels per inch(ppi) and are referred to as raster devices becausethey display with scan lines. Many desktop proofersalso print with raster data—ink-jet printers, dye-sublimation printers and copiers print withouthalftone screens in most cases and range between200-1,400 ppi. (There are new large-format printersthat can get away with clearly reproducing imagesat a resolution as low as 50 ppi.) This allows theraster device at each end of the printing process(monitor and printer) to communicate with the sameppi language when image-quality concerns comeinto question.

Establishing a ratioTraditional printing and halftone proofing devicesuse a halftone dot computed by establishing a ratiobetween ppi and lines per inch (lpi). To maintainhigh-quality images this ratio is 2:1; in other words,for an image to print with high quality at 150 lpi thedigital file should be at 300 ppi. Despite this,acceptable results can be achieved all the waydown to 1:1—primarily with less critical work onnewsprint and other inexpensive paper.

Step 4: Sharpening images

Sharpening in the digital worldIn the analog world, image sharpness (an image’sdegree of clarity) is an elusive ideal directly related to camera price. If you’ve ever compared atransparency from a high-end 35mm camera to thattaken by an average one, you know what we mean.But when the image is captured digitally (digitalcamera or scanner), the tonal gradations of theimage are converted into a grid of pixels that almostalways needs to be, and can be, enhanced throughdigital sharpening.

Fortunately, in the digital world this is relatively easyto do. Today most image-processing programshave sharpening built-in, offering an inexpensivemeans to render images exactly the way you want.Determining just how much sharpening is needed,however, requires a fair amount of input from theuser because it’s subjective, and the amount ofsharpening required can change relative to theimage, the size it’s used and the output process.

Unsharp masking (USM)The commonly used term ‘unsharp masking’ is aholdover from traditional photographic processesused by color separators: a special piece of filmwas prepared that rendered an image purposelyblurry. When combined with the original negative itincreased contrast along areas where the tones

abruptly shifted. Today most scanners and softwareprograms analyze only the digital information, notthe actual image.

USM and PhotoshopDigital sharpening works by selectively addingcontrast to edges, making the picture appearsharper. This is controlled by programs such asPhotoshop that provide the following settings whenusing unsharp masking:

Amount: When the unsharp masking algorithmconsiders the pixels of an image, it notes areas ofcontrast. Then it adds density along the dark edgeand subtracts density along the light edge.‘Amount’ here refers to how dark and light theseedges are compared to the original (increasing theamount makes dark areas darker and light areaslighter). We recommend you increase the defaultsetting closer to 100 to begin experimentation. Radius: This looks at the size of the area that will beaffected. The larger the number, the greater the areaaffected. If your image includes lots of detail, keepthis number low. We recommend you increase thisnumber as file size increases. For a standard screenresolution, a radius setting of 0.5 works well; for astandard printing resolution, increase this number toabout 1.5. Images with low tonal differences and without fine detail can be improved by increasingthe setting to about 3.0.

Threshold: This determines what level of contrast tosharpen. At a setting of 0.0 the program looks ateverything; as this number is increased it looks atless. This number becomes critical with flesh tones.Unless you’d like to see every pore, keep thissetting over 6.0. A recommended base setting forprint images is 125, a radius of 1.5 and a thresholdof 3.0.

Sharpening tips Sharpening should be the last operation, it’s best to wait until the image is ready for output before determining sharpness. Flesh tones can look verybad if oversharpened. Sharpening is a subjectivedecision and should be based on printed testsimages—files onscreen almost always lookoversharpened. Expect the grain to increase when you sharpen.

Also worth notingOne of the most effective ways to sharpen yourimage is to convert it into CIE L*a*b* color. In thisformat the L, or luminance, channel has no colorinformation, and sharpening it creates very smoothresults and avoids the color fringing common onsaturated images.Most professional scanning programs such asLinoColor have additional controls that allow you todetermine the intensity of the contrast on both thelight and the dark sides.

Why we don’t presharpen imagesImages differ greatly and the intent of your design issomething we never want to compromise orsecond-guess. A ‘generic’ level of sharpening limitsyour creativity, as we mentioned earlier, sharpeningis subjective.Printing environments and intent can vary widely. Ifwe pre-sharpened our images, the quality of yourprint could be sacrificed. Different processes andenvironments require different amounts ofsharpening and what looks good onscreen couldlook terrible in print, or vice versa.

We JPEG-compress all our images on the highestsetting (least data loss, biggest file size) to ensurethat the least amount of image quality is lost. If wepre-sharpened and then JPEG-compressed there’sa strong chance the image would end up blotchy.

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This section shows you how to color convert usingprofiles in Photoshop. However, it is not intendedto recommend particular settings because allworkflows and environments differ and it wouldbe an impossible task to cater for everyone.

Why use profiles?Profiles provide reference points for devices used inyour workflow. They give Photoshop moreinformation on color e.g. what color space an imagewas scanned into, and what color space the imagewill be printed in. When this information is known,Photoshop is able to convert more intelligently fromone color space to another.It provides more consistent, reliable results and alsoputs more control on your desktop, saving time andmoney.

Where are profiles stored?Mac OS 9 ICC profiles are stored in System Folder /Colorsync ProfilesMac OS X ICC profiles are stored in Library /Colorsync / ProfilesOn Windows 95/98 ICM profiles are stored inWindows / System / ColorOn Windows XP/2000 ICM profiles are stored inWindows / System 32 / Spool / Drivers / ColorOn Windows NT ICM profiles are stored in WinNT /System 32 / Spool / Drivers / Color

Please note:Once you have installed a new profile, you will haveto quit and relaunch your applications.On all platforms delete any unused profiles. This willreduce launch time of your applications.Try to avoid amending the profile name as this maycause problems. If you must change the name, usea program such as profile editor.

Step 5: Color conversions

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200119233-001 Jonathan Kirn

Photoshop 6, 7 and CSTo begin using profiles go to Photoshop / Color SettingsHere you are given various choices based on the wayyou want to work. Unless you are fully knowledgeableon the subject of profiles, we recommend that you don’tcheck the embed profiles boxes. There is now a handydescription paragraph of everything to help youunderstand exactly what you are doing.

RGB to CMYK conversionsGo to Image / Mode / Convert to Profile The source color space is automatically detailed foryou. In this case it is set to ‘Tiff RGB’ which is GettyImages’ chosen color space. Then select the colorspace you want to convert into, e.g. choose the optionthat best suits your workflow.

You also get the choice of Engine and Rendering Intent.Take some time to test these fully and understand whatkind of results you get using different settings.

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Instead of CustomSettings, Photoshop alsohas some pre-set profilesthat you may find useful

AbsorptionIn printed media, it’s the property that causes thesurface to take up colorants in contact with it, suchas ink. With digital media, it’s the loss of light ofcertain wavelengths as it passes through a materialand is converted into heat or other forms of energy.

Black pointWhen referring either to a monitor or a printer, the black point is the darkest point that it canachieve neutrally.

BrightnessAlong with hue and saturation, brightness is anattribute of a color. It’s the perceived quality ofluminosity of a visible object.

CalibrationThe process of ensuring that color reproductiondevices are set to a known state, sometimes usingindustry standards or manufacturer’s specifications.

CharacterizationThe process of creating an ICC profile thatdescribes the unique color characteristics of colorreproduction devices such as monitors, scanners,color printers and four-color presses.

ChromaThe amount of color in a color sample, e.g. gray has a chroma value of 0 while a neon sign has a high chroma value. Chroma is also referred to as Saturation.

CIE L*a*b*A color model using lightness (L*) and two colorvalues (a* and b*). The color coordinates definewhere a specific color lies in a Cartesian graph: thea* value defines the red-green axis and the b* valuedefines the blue-yellow axis. The L* value adds athird dimension to the color space.

ClippingThe severe transformation of colors re-purposed toanother device’s color gamut. These colors liewithin the original color space but outside thedestination color space.

CMMColor Management Module. A set of coloralgorithms used to transform color values. The CMM is the engine that calculates color values based on predefined color characteristics in the ICC profiles.

CMSColor Management System. This is system-levelfunctionality that maps, or translates, the colorspace of one device to the color space of another.ColorSync on the Mac OS and ICM 2.0 onWindows are examples of CMSs.

CMYKCyan, magenta, yellow and black (key), thecolorants used in the four-color process ofsubtractive, full-color printing.

ColorantsMaterials such as pigments, dyes and inks used by a device, primarily a printer, to reproduce colors.

ColorimeterA color-measuring instrument. The colorimeter uses a three-color model, usually RGB, todetermine color characteristics of output devices.Colorimeters are usually used to calibrate andcharacterize monitors.

Color modelThe dimensional coordinate system used tonumerically describe colors. Some models includered, green, blue (RGB); hue, lightness, saturation(HLS); cyan, magenta, yellow, black (CMYK);lightness, a, b (Lab).

Color SeparationThe conversion of red, green and blue (RGB) color data used by a computer monitor andtransparencies into cyan, magenta, yellow, and black (CMYK) data that is used in the printing process.

Color spacesA theoretical three-dimensional color system inwhich the axes of color, hue, saturation andbrightness are represented.

Color glossary

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ColorSyncAn Apple system software architecture that enablessystem level color management in conjunction withICC profiles.

Delta EDistance in the CIE L*a*b* color space between two colors. The delta E variable can be used to test color tolerances within a color-managedenvironment.

DensitometerAn instrument used for reading the amount of lightreflected by a surface or transmitted by an object.Densitometers are often used to measure thedensity of process-color inks on press. Thesedensity readings can then be used to calculateother values like dot gain and color difference (Delta E). By measuring emulsion densities, densitometers are also commonly used to analyze color characteristics of film.

Dot gainNet percent increase in halftone dot size (or tonevalue) throughout the tone scale of a press sheet.Dot gain is a consequence of ink soaking into paper and spreading. A dot gain of 20% means that a 50% tint reproduces at 70% apparent dotarea on paper.

DPIDots per inch (dpi) is measurement of outputresolution referring to number of dots in an inch.Also applicable to setting scanner input.

EPSEncapsulated post script (EPS) is a common way of saving an image, primarily suitable for savingillustrations from programs such as Illustrator and Freehand.

GammaIn monitors, this is the logarithmic relationshipbetween the voltage input and the brightness of amonitor. The brightness of the monitor in relation tothe voltage input is expressed as x2.2 where x is thevoltage input and 2.2 is a power function calledgamma. Gamma can be thought of as a hard-wiredcontrast curve.

GamutThe total range of colors reproduced by a device. A color is said to be ‘out of gamut’ when its positionin one device’s color space cannot be directlytranslated into another device’s color space. For example, the total range of colors that can bereproduced with ink on coated paper is greater thanthat for uncoated newsprint, so the total gamut foruncoated newsprint is said to be smaller than thegamut for coated stock. A typical CMYK gamut isgenerally smaller than a typical RGB gamut.

GCRGray component replacement (GCR) uses black ink to replace cyan, magenta, and yellow inks. The black replaces neutral color values of the threecolored inks throughout an image. The amount of black replacement is usually defined as apercentage GCR.

GIFGraphic interchange format (GIF) is commonly used for graphics displayed on the world wide web, originally developed by CompuServe.

HalftoneIn print, a pattern of various-size dots used togenerate an illusion of varying densities or shades.

HueThe basic color of an object, such as ‘red,’ ‘green,’‘purple,’ etc., defined by its angular position in acylindrical color space, or on a color wheel.

ICCThe International Color Consortium (ICC) wasestablished in 1993 by eight industry vendors forthe purpose of creating, promoting andencouraging the standardization and evolution of an open, vendor-neutral, cross-platform colormanagement system architecture andcomponents. See www.color.org.

ICC ProfileA file that describes how a particular device (e.g.monitor, scanner, printer, proofer) reproduces color(ie. its specific color space).

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Input, Monitor and Output ProfileAn Input profile is used for a scanner or digitalcamera, a Monitor profile for an LCD or CRTdisplay, and an Output profile for a printer orimagesetter.

InterpolationA computer process that increases or maintainsimage resolution when the image is enlarged or reduced.

JPEGJoint photographic experts group (JPEG) files are compressed data commonly used for file transportation.

LinearizationA specific type of calibration where an outputdevice is adjusted to deliver a straight-linerelationship between input and output.

Neutral colorsBlack, white or gray—colors not associated withany single hue.

PixelA tiny picture element that contains red, green, andblue information for color rendering on a monitor ora scanner. When generating colors, pixels aresimilar to dots of ink on paper. A monitor resolutiondescription in terms of pixels per inch (ppi) is similarto a printer resolution description in terms of dotsper inch (dpi).

PPIPixels per inch (ppi) refers to the resolution of thedigital file, pixels per inch.

Process PrintingOutput from a printing press that uses four colors(cyan, magenta, yellow and black) to create theillusion of continuous tone images. For that reason,cyan, magenta, yellow and black are also known asprocess colors.

ProoferA printing device used to simulate color achievedon press. A service bureau uses proofers to createimages as contracts (also called a contract proof) tomatch in the final output from the offset press.Traditional analog proofers create prints from theactual separation negatives. Examples of these

proofs are MatchPrint, Fuji color art, or cromalins.These proofers do not use the film used for the finalprint job. Instead they simulate color using ink-jet,dye-sublimation or other technology.

Render IntentThe method a CMM uses for converting (ie. mapping) colors from one device’s gamut to another. The four methods are perceptual, saturation, relative colorimetric, and absolute colorimetric.

Soft ProofingThis is when you can view the finished file on yourscreen instead of having a hard copy e.g. digitalmatch print or cromalin to view. Soft proofing canprovide a very economical means of proofing.

SpectrophotometerAn instrument for measuring color samples atspecified increments throughout the visiblespectrum. Unlike densitometers and colorimeters,the spectrophotometers measure discretewavelengths of light referenced to humanperception. Spectrophotometers are the mostcommon tool for measuring printed color samplesused to create ICC profiles.

sRGBStandard RGB is an RGB specification promotedby Microsoft and Hewlett-Packard. It specifies agamma of 2.2 and a white point of 5,000ºK.

TIFFTagged interchange file format (TIFF) is one of themost common image formats.

TIFF RGBThis is Getty Images’ color space, from Heidelberg.

UCRUndercolor removal (UCR) involves the replacementof cyan, magenta, and yellow inks with black ink inthe dark, shadowed areas of an image to lower thetotal amount of ink applied to the paper.

White PointHow white is reproduced. On a monitor it is thecombination of all three red, green and blue primarycolors at full intensity, as measured by its colortemperature in ºK. Necessary as a reference point incalibration and characterization.

What is Color Management and what will it do for me?Color Management provides the ability to predictand control accurately image elements from onemedia or color space to another. It is very commonfor an image to be used on a website and output tovarious types of printing conditions, perhaps indifferent parts of the world. Conditions for differentprocesses and vendors can vary widely. ColorManagement gives you the ability to re-purposeimages with confidence. Your images will look asgood as they can no matter what process is usedfor reproduction.

How does a CMS work?Simply put, CMS use profiles, or mathematicaldescriptions of the color in devices, to transform thecolor between those devices. For example, theprofile for the scanner and the profile for the monitorcan negotiate the correct color from the scanner todisplay on the screen. This takes place through acolor matching method from a variety of vendors atthe operating system level on Macintosh computersand through some individual applications on Wintelmachines.

What types of output are suitable from your digital files?Getty Images digital files capture the full gamut ofcolor and are never limited to what can bereproduced in standard four-color printing.Photographic output and extended range systemslike Hexachrome will not be compromised whenusing our files.

Why not give customers files in CMYK?There is a good chance that any CMYK file wewould provide would not be appropriate for ourcustomers printing needs. CMYK is extremelydevice-dependent. Paper, ink, press conditions,how you prepare the black (UCR-GCR) andnumerous other variables determine what colorsyou can print. It is best for you to create your CMYKfrom our RGB files for the specific needs of yourprinting process.

Having said that, some of our third-party partnersdo offer CMYK files.

What is an ICC profile?A profile is a data file that conforms to theInternational Color Consortium standard andrepresents a mathematical description of the rangeof colors a device can capture, display or print.

Why would I want to use profiles?Profiles are the building blocks of ColorManagement. They provide a reference for devicesused in your workflow. By creating these referencefiles, the profiles, you are able to adjust colorthroughout your workflow based on the uniquecharacteristics of these devices.

How do I use the TIFF RGB source profile?The source profile is a ColorSync/ICC mathematicaldescription of the color in our files. The informationin this file is used by Color Management awareapplications to transform the color to your screenand to other output devices. It is the ‘from’ part of the ‘from/to’ equation. Because your CMS has a reference for the source data it is possible to convert very accurately to the RGB used on web pages and the CMYK used in proofing andprinting applications.

What does the profile do to the images?A profile does nothing to the image. A profile isa description of the color in the image.

It communicates to a CMS so your monitor and other color devices can use the color in theimage correctly.

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FAQsbf0119-001 A

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Why doesn’t the image on my screen look like the proof I received from my supplier?Use the ColorSync Control Panel or the AdobeGamma utility (OSX, use Monitor Preferences) tobuild a generic profile of your monitor. If you areanything more than a casual user, you can use aspecial tool, called a colorimeter. If you decide to purchase a colorimeter, then this will create an accurate profile of your monitor.

Colors appear different in various lighting conditionsso when viewing the proof, the light source mustprovide continuous white light, as this can play a bigpart in the color you perceive. We are confident thatif you follow the guidelines and work in a well-controlled color environment, you will soon be ableto make many of your color decisions from yourscreen in this stable environment.

My printer wants CMYK files, what is the bestway to convert them?There is really no such thing as standard CMYK.Paper, ink, linescreen, and numerous other variablescan dramatically change the optimum CMYK file fora particular project. Talking to your printer canprovide you with the information you need to makeaccurate CMYK files for final press output. Printersmay also be able to provide you with an ICC profilefor their printing process. You may also findalternative profiles that will work with your printer’soutput conditions. Bear in mind that custom profilesusually provide better results than generic profiles.

What kind of output devices can I profile?Almost any type of output device can be profiled.Monitors, scanners, proofers, digital presses,offset presses, etc. Even film plotters andtransparency/duratrans output devices canbe accurately profiled.

Is my printer an RGB or CMYK device?Most printers image using cyan, magenta, yellow,and black inks. Some of the latest printers use inkssuch as light magenta, light cyan and light black inaddition to the standard CMYK inks. If theseprinters accept postscript files then it is probablybest to profile these devices as CMYK devices. Ifyour printers do not accept PostScript files it isprobably best to profile these devices as RGBdevices.

For more information on this please consult yourprinter manufacturer.

How does the profile benefit the customer?The result of using the ICC Color Managementtechnology and the TIFF RGB profile is greatercontrol of color on your desktop and that cantranslate into savings in time and money. Our profileallows the user to accurately make assumptionsabout the true nature of the RGB color defined inour image files. Armed with this definition (profile),you can use Getty Images files in ICC-awareapplications while keeping the image in a relativelydevice-independent state. This helps eliminatesome unnecessary degradation in the RGB data.

Online color resourceswww.color.org (ICC home page)www.adobe.comwww.apple.comwww.gretagmacbeth.comwww.pantone.comwww.chromix.comwww.praxisoft.comwww.color.comwww.xrite.comwww.chromaticity.com

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