Photoshop Lab Color- P5: LAB has a reputation for enormous power, yet virtually all reference materials that advocate its use illustrate its capabilities with a single class of image. This chapter introduces the basic LAB correction method and explains why it is so extraordinarily effective. if you happen to have a picture of a canyon. | Entering the Forest Myths and Dangers 121 122 Chapter 6 things to worry about than bit depth and conversions. As for Figure I state categorically that the two versions are identical for any conceivable professional purpose. And Why Not Look If You Please A boring bystander is unfortunate enough to be confronted by an enraged Cyrano who imagines the man is staring at his nose. CYRANO. What do you think Is it not a phenomenon THE BORE. But I knew better than to look CYRANO. And why not look at it if you please THE BORE. I was. CYRANO. Does it disgust you THE BORE. Monsieur. CYRANO. Perhaps you do not like its color At the close of the scene the bore is lucky to escape by being smacked on the side of the head rather than being run through with an épée. A good cuffing might do wonders for his counterparts in the Photoshop world those who are so certain of their ground that they know better than to look. And now that we have looked and know the correct answer it must be conceded that sometimes the theory seems so obviously true as to render any alternative inconceivable. This is a compelling example. How can moving to LAB not cause damage We re throwing away so they say a third of the colors Translation the original RGB file consists of three channels each of which has 256 possible values or levels of tonality. If we consider two channels simultaneously each of the 256 values in the first channel has 256 more possibilities in the second for a total of 65 536 possibilities. If we add a third channel each of these 65 536 has 256 more for a grand total of 16 777 216 possible combinations. I don t know how many distinct colors are in the original version of Figure but it isn t 16 777 216. For example there s no bright yellow anywhere. 210R210G40B which is a fairly subdued greenish yellow isn t likely to be found. And neither is anything with higher red green or both coupled with an equal or lower blue. If you agree 86 756 possible colors have just fallen on their .
