Chapter Objectives. Color Management. Color Management. Chapter Objectives 1/27/12. Beyond Design

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1 1/27/12 Copyright 2009 Fairchild Books All rights reserved. No part of this presentation covered by the copyright hereon may be reproduced or used in any form or by any means graphic, electronic, or mechanical, including photocopying, recording, taping, or information storage and retrieval systems without written permission of the publisher. Beyond Design By Sandra J. Keiser and Myrna B. Garner ISBN: PowerPoint developed by Elizabeth Law GST R Chapter Objectives Review physics of color science Review impact of color decisions throughout supply chain Define terminology used in color management Outline process for visual and digital color approval Color Chapter 5 Beyond Design Chapter Objectives 4 Color Identify variables that affect color management Analyze impact of technology on color measurement Color management process of controlling outcome of color from initial concept (chip, swatch, yarn, or sample) to final production output in a way acceptable to the consumer 5 6 1

2 Color Color concept determined by either the trend or design department Matched to color standard from a color specification system which identifies colors that can be achieved on various fabrics required for the group Color Color Specialist approves lab dips in-house to assure that lab dips match color standard and other fabrics used within the group Dyers and finishers dye sample must match color standard; ensure production yardage consistency Quality assurance color fastness requirements Colors must not bleed, fade, or change under normal conditions of use and care 7 8 Color Color Science Variation must be managed through color sorting Color consistency imperative; customer is mobile and may buy one piece in-store, another online Different colorways may shrink differently during processing Color visual perception of certain wavelengths of light by retina of eye Nanometer one millionth of a millimeter, used to measure light waves 9 10 Color Science Color and Light The human eye Sees wavelengths in a range from 400 nanometers (deep blue) to about 700 nanometers (deep red) Distinguishes about 10 million variations of color Not all colors can be reproduced with available dyes and inks or on all available materials Colors may appear different under different types of light Variety of lighting environments a challenge for color matching Color constancy color perceived to be the same regardless of light source Color inconstancy/flair single color reads differently under various light sources (related to hue, rather than color recipe)

3 Color and Light Metamerism - the perceived change in color between a pair of samples matching under one light source but not under another source Pigment - the substance that imparts color to another substance; color perceived as some wavelengths of light are absorbed and others are reflected Color Attributes Munsell Color System describes and identifies color and color relationships (most widely used) Hue Value Distinguishes one color family from another Chromatic colors have a hue Achromatic colors of black, white, and grey have no hue Hue and color are not synonymous Hue has one attribute Color has three attributes: hue, value, chroma Value - distinguishes light colors from dark Tint - light color (pastels) Shade - color mixed with black to decrease value and darken hue (navy) Color s perceived value depends on percentage of light reflected from surface Value Chroma (Intensity) Lightest color white reflects most of light; absolute black reflects no light; gray absorbs and reflects some light Munsell gray scale - ten value steps, with black at zero Chroma - color s saturation, or degree of departure from the neutral of same value Determined by amount of pigment in color Hues with 100 percent intensity are fully saturated with pigment

4 Color Temperature Used to describe a color s apparent warmth or coolness in relation to another color Not considered true attribute of color, but universal human perception that hues appear to be either warm or cool Color Temperature Warm colors: yellow, orange, red Cool colors: green, blue, and violet Temperate colors (intermediate) red-violet, etc. Designers use to evoke image (cool-sea green) Creating and Mixing Colors Complicated because colors depend on medium from which they are created Primary colors - minimum number of hues that can be mixed to make greatest number of other colors Secondary (intermediate) colors - two primary colors mixed together Additive Color Mixing System How colored light is mixed Red, green, and blue or blue-violet primaries Yellow, magenta, and cyan secondaries (CMY) Mixing all three additive primaries = white Creates greatest range of colors Subtractive System How pigments are mixed Paints, inks, dyes, other color media all absorb certain wavelengths of light, which enable an object to absorb some light waves and reflect back others The more pigments blended, the more light absorbed and the less light reflected (thus, subtractive) Subtractive System Simple subtractive - used for mixing thin films Complex subtractive - used for mixing thick films Relative system; pigment proportions must be adjusted to achieve perceived, balanced mix

5 Combining Color Mixing Systems Not possible to create every color with either the additive or subtractive mixing systems Chroma defines the color range attainable in any particular medium (paint, fabric, print) Gamut - entire range of colors that can be achieved in a medium or materials 25 Combining Color Mixing Systems Artists use additive mixing on computer Prints applied to fabric use subtractive mixing for dyes or pigments Professional printers expand their CMYK (cyan, magenta, yellow plus black) primaries with spot colors Pantone Hexachrome Color system is a six-color high-quality printing process that reproduces more accurate colors than the CMYK system in order to meet or exceed the gamut obtained with RGB color mixing used in fabric dying and printing 26 Seasonal Color Palettes Color palette selection critical to meeting profit objectives Too many colors too costly to produce Too few don t attract customers Colors selected for a palette group should share common attributes so they coordinate Seasonal Color Palettes Monochromatic - several colors of same hue Analogous - adjacent colors on color wheel Complementary - colors opposite one another on color wheel Color s temperature also considered Relating Color Palettes to Target Markets Age and Life Stage Fashion Level Skin Tone Ethnicity Geographic Location End Use Managing the Color Story Color groups developed around specific theme, named, and used as marketing tool Multibrand product developers manage up to 400 different seasonal color palettes

6 The Color Process Color Standards - color samples by which fabrications and notions can be matched to ensure color consistency Facilitate color management throughout global supply chain Color Specification Systems Standards for accurate communication Available on different materials or substrates Range of colors indicates the gamut of color that can be achieved on that medium Capacity to be replicated digitally and relate to appropriate dye recipes Color Notation Systems Visual representations of how colors relate to one another (color solids) Numerical system indentifies each color within the color solid to help visually identify, match, and reproduce colors Munsell system - uses hue, value, and chroma, (H V/C); takes shape of sphere/ amoeba Commercial Color Identification Systems Two commonly used, commercially managed, code-identified color libraries Allow for specification of color transmitted via phone, fax, Internet SCOTDIC applies Munsell Color System to fabric Pantone Matching System uses six-digit numerical code to define color s position in color space Color Approval Process Once seasonal color standards are selected, master list is developed that identifies colors Sourcing partners must match any fabrics or trims they supply to the color standard specified Order 4 x 4 color standard from designated color library for matching Or rely on spectral reflectance data supplied by the product developer to interpret the color requested Visual Color Approval Lab dips are dyed samples of the actual fabric or finding to be used in production Sourcing partners have two weeks to submit lab dips after receiving color specifications The product developer either approves the lab dips or requires additional samples to achieve a better match

7 Digital Color Approval Color measurement systems and computer software that allows supply chain partners to measure color reflectance data accurately enough to match color standards to digital color libraries enabling digital approval of lab dips Final approval achieved in half the time of traditional color matching process Prints and Yarn-Dyed Fabrics Prints and yarn-dyed fabrics must be submitted as one full repeat of pattern Strike-off an actual fabric sample or computer-generated paper copy of one pattern repeat with a color key of all colors that appear within the print Color Measurement Instruments American Association of Textile Chemists and Colorists (AATCC) publishes standards for visual and instrumental measurement of color Equipment, lighting, and viewing conditions under which color is measured must be parallel Colorimeters use filters combined with light source and detector to emulate threecolor response functions of the eye; best for shade sorting Spectrophotometers compare illuminating light with reflected light; preferred instrument Illuminants Viewing Geometry Illuminants light sources under which lab dips are measured Lab dips should be measured under at least two light sources to reduce matching problems Measurement technique, conditions and equipment must be standardized for results to be reliable Measurements should be taken several times and based on the largest viewing area available using the specified equipment Color measuring equipment requires opaque samples to be accurate; transparent fabrics should be folded to achieve sufficient opacity Samples may be rotated for four or more measurements to compensate for fabric construction

8 Color Measurement Procedures Color Measurement Procedures standardized measurement techniques as well as conditions and equipment Interpretation of Color Measurement Data Instrumental color measurements are calculated from colorimetric data The Commission Internationale de l Eclairage (CIE) system of chromaticity coordinates refer to the light reflected by the surface of the object when it is illuminated by a standardized light source CIE system can be cross-referenced to the Munsell or Pantone Color systems so that light measurements can be translated to subtractive pigment data using either CMYK or RGB primaries CIELAB system is a variation if CIE that adapts chromacity values for subtractive primary color mixing where the L* measures the lightness coordinate, the a* measures the red/ green coordinate, and the b* measures the yellow/blue coordinate Factors Affecting Color Many factors affect color communication and how color is perceived Challenge: arrive at the same color on variety of garment components Fabric Fiber content Surface appearance (pile, shiny) Colorants may change fabric s reflective properties Human Vision Color Calibration Many things influence how we see color type of light direction of light source direction of viewing Background Adaptation of observer s eyes Aptitude for judging colors varies Viewed from different sources Computer configurations and hardware differ between designers and vendors Printer ink levels, usage levels, and user settings may produce different colors Devices must be calibrated and profiled to get an accurate measurement of color