Photoshop Lab Color- P11

Photoshop Lab Color- P11: LAB has a reputation for enormous power, yet virtually all referencematerials that advocate its use illustrate its capabilities with a singleclass of image. This chapter introduces the basic LAB correction methodand explains why it is so extraordinarily effective. if you happen tohave a picture of a canyon.
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Photoshop Lab Color- P11 Once for Color, Once for Contrast 301have them, a blend won’t change things. If Curving the L channel would help, but wenot, the blend by definition will bring them should try to engineer extra weight into thecloser. Thus, the blend isn’t troubled by neu- picture first. We’ve done it earlier with skies;trals that are wrong at some darknesses and now we’ll do it with the entire image.right elsewhere. As pointed out earlier, in faces that are Red objects are more common than any normally lit, the green channel is almostother kind. Any such object needs to be always the best. This image is not normallylighter in the red channel than the other two, lit. The face is much lighter than it shouldbut it should have roughly similar values in be, so the rule doesn’t apply, any more thanthe green and blue. Blending the green chan- it would if the face were in shadow.nel into the blue is usually the best way to cut I made a third layer by duplicating the sec-down a yellow cast. It brings closer together ond, and applied the blue channel, acceptingnot only the neutral areas, but also the reds. the default choice of the blue from a merged Not here, though. The green channel is version of the bottom two layers. Choosingmuch lighter than the blue in the priest’s the bottom layer would have been a mistake,green chasuble, which plays a big role in the because its blue was so dark that it didn’timage. If he were wearing some other color, carry detail in the green chasuble. Once light-I’d use the green for the blend. As matters ened with the first blend, it became morestand, I’ll go for the red channel. usable for the second. I chose 60% opacity To get Figure 14.11B, therefore, I created a and, of course, Luminosity mode. That’snew layer and used the Apply Image com- Figure 14.11C. Then into LAB, being sure tomand to blend the red into the blue, picking flatten the image only after the conversion32% opacity out of a hat. I used Lighten was complete, and you know the rest of themode, which restricts the blend to areas in drill. Figure 14.11D is the final version.which the red in fact starts out lighter thanthe blue. Here, that comprises the entire A Vote for Fluencyimage, so Normal mode would have done This picture is not of an actual churchthe same thing. But we certainly wouldn’t ceremony. Rather, the priest is posing for awant to darken the yellow in some hypothet- professional photographer using top-notchically bright blue or cyan object, so being in equipment. Everything is as controlled as itLighten mode is good practice. can be, except that it would take either divine With washed-out originals like this one, if intervention or a good knowledge of the LAByou do a lightening blend to try to regularize language to compensate for the ambientthe color, usually you should set the layer lighting. According to the photographer, thisblending mode to Color, meaning that Photo- scene featured not just a mix of fluorescentshop is to pick up the detail from the bottom and incandescent lighting, but also flood-layer and use the top one for color only. I lights of two different colors.didn’t do that, because I needed a lighter In short, the picture is a tougher customerlayer for the next move. than it looks, because it’s full of casts and The biggest issue I have with the original counter-casts that are disguised by overallis that the face scarcely exists. The whole lightness. Yet two blends that together tookpicture needs to get darker to make any kind less than a minute sufficed to get it on theof credible fix. I don’t mind if the flowers or right track. Figure 14.11C may not be attrac-the rear wall lose a little color in the process, tive itself, but it’s easy to fix in LAB. The orig-because I think the priest is the focus. inal, Figure 14.11A, is another story.302 Chapter 14 The secret is to think in the foreign lan- with one another (and with LAB correction guage of LAB even while speaking the RGB generally) in a bewildering variety of ways. idiom. Like a new language, you have to In deciding when to use them, remember speak it slowly at first. We’ve only done four that certain things work about the same in images in the course of a 20-page chapter. RGB and LAB, and other things are quite With practice, it becomes very fast. different. Those radical differences are the And, like a foreign tongue, knowing a few ones you have to cater to. Trying to create phrases and grammatical constructions gives extra detail with curves or some similar only a little hint of how rich and rewarding command may work slightly better in one the fully realized language can be. By neces- colorspace or another, but you’ll be able to sity, this is a brief overview. We had space for fake it elsewhere if you have to. only one example of each of the four major The color-busting capabilities of the A and categories: using RGB curves first to change B channels, though, can’t readily be faked in contrast only and then to change color only; RGB. And the ability to use a particularly and then using RGB channel blending in the good RGB channel to strengthen an image same two ways. These techniques interact ...