Page 136 - Graphic Design and Print Production Fundamentals
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4.12 Summary

            Alan Martin







            In essence, colour management is a translation process. The tools and precepts of colour science give
            us the lexicon to populate the dictionaries of each of the devices we use in our graphic technology
            workflow. Our device’s dictionary is the colour profile we generate with the help of a colour target, an
            instrument to measure the target and colour management software to process the measurements.

            Since the device’s dictionary (colour profile) defines the specific RGB or CMYK values of that device
            in a device independent colour language, we have a conduit between any two devices. By aligning
            the device independent values between the two devices, we can translate from the device dependent
            values of our source to the new RGB or CMYK values at our destination to provide a common colour
            experience.

            With an understanding of how to configure our standard graphic arts applications to effectively use
            our device’s profiles, we can make successful colour translations happen in our real-world production
            scenarios. Successful colour translations provide the improved productivity that comes with
            predictability and confidence in process control.




              Questions to consider after completing this chapter:




                      1. What are the three components of the colour event?
                      2. How does visible light relate to the electromagnetic spectrum?
                      3. How does the zone theory of optical systems resolve the apparent incompatibility of trichromacy
                         and opponency?
                      4. What is the importance of the Lab colour space?
                      5. Define Delta E.

                      6. Which of RGB, CMYK, and Lab are device dependent colour spaces, and which are device
                         independent colour spaces?

                      7. How does a spectrophotometer work?
                      8. What is the purpose of a colour target?
                      9. What Mac OS utility can be used to view colour profiles?

                     10. How does a measurement file relate to an ICC profile?
                     11. What is the vcgt tag in a display profile?
                     12. Name the common characteristics of output, display, and input profiles.
                     13. What characteristics are unique to each of output, display, and input profiles?





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