Professional Information Technology-Programming Book part 27 potx

Changing Hue/Saturation When the image interpretation you're after is all about color that goes beyond what you're likely to shoot in the original and exists only in your imagination, it

6.3 Using Blend Modes on Adjustment Layers

You may think that the adjustments you made to your image in Camera Raw may have made it unnecessary to go through the adjustments in this chapter Never mind Don't delete the adjustment layers created by your Workflow Layers Action until you've done everything you want to the image You can mask either of those layers to use for a targeted adjustment (see Chapter 7) or use a Blend Mode with the layer

Here's another good reason you shouldn't delete them: even when no adjustments are made in an adjustment layer, Blend Modes can have amazing effects on your image And remember, because you did it with an adjustment layer you can

experiment all you want I will show you the three that are most useful, each in a before and after on the same image Remember, you can vary these effects

considerably by adjusting the Opacity and Fill sliders for the adjustment layer

Luminosity

Neutralizes color shifts, as shown in Figure 6-24

Figure 6-24 An image before and after adding a Curves layer in Luminosity Blend Mode

Screen

Creates a high-key effect, which is especially useful for creating a dreamy mood or adding glamour to a female portrait (see Figure 6-25)

Figure 6-25 An image before and after adding a Curves layer in Screen Blend Mode

a classical or dark and creepy mood (Figure 6-26)

Figure 6-26 An image before and after adding a Curves layer in Multiply Blend Mode

6.4 Changing Hue/Saturation

When the image interpretation you're after is all about color that goes beyond what you're likely to shoot in the original and exists only in your imagination, it's

definitely time to think about the Hue/Saturation adjustment layer This is once instance where it's especially useful to have the nondestructive nature of an

adjustment layer on your side This command makes it possible to boost the

intensity of colors far beyond anything your screen can see or a printer can print

So before you even start to use it, turn on the View Gamut Warning command, especially if you plan to boost saturation rather than reduce it

As you probably know or will see as soon as you open the dialog, changing the intensity of colors isn't all this dialog does It also lets you change the overall Hue

or color balance of the image Yet another slider lets you change the brightness of the image's midtones and is especially worth giving a try when you want to bring the image back into gamut by sacrificing brightness for color intensity One again, keep the Preview box checked so that you can use these sliders interactively

6.4.1 When to Change Saturation

If you've made your shot in dull or foggy lighting conditions, increasing saturation may be the way to bring the image back to life Or sometimes you just want to increase the impact of a colorful subject, such as a punk hairdo or an iPod billboard (see Figure 6-27)

Figure 6-27 A colorful image before and after having its color saturation

enhanced

Granted, the Figure 6-27 is an exaggeration Fujifilm discovered sometime ago adding saturation to the colors of nature often adds to the appeal of an image

Forests look greener, wild flowers pop, and skies are bluer

On the other hand, if you turn on Gamut Warning and start seeing solid gray

6.4.2 Mapping Hue/Saturation to a New Color Model

The Hue/Saturation adjustment layer can be used to completely remap the colors in the image This can often be a wonderful punk or fantasy effect Note that there are two color spectrum ramps at the bottom of the Hue/Saturation dialog (Figure 6-28)

If you go to the Master menu (above the sliders) you will see the names of all the adjustable color ranges Choose one and the lower color ramp will become

bracketed; this will allow you to adjust the bracket to widen or narrow the range of colors Then, as you move the Hue slider the colors within that target spectrum are remapped

Figure 6-28 The Hue Saturation dialog

After playing with the possibilities for a while, try changing the Opacity and Fill of the Hue/Saturation layer You can also try painting black or dark gray into the Layer Mask to bring portions of the image back to the original colors In the before and after image in Figure 6-29, all of these adjustments have been done in the righthand image

Figure 6-29 In the after image, the colors for yellow have been remapped by

moving the Hue slider Also, details in some of the shadows, such as the interior of the closest sailboat, have been brought back to life by masking them from the effects of the Hue/Saturation adjustment layer

NOTE

You can use the eyedropper in the Hue/Saturation dialog to pick a color to

transform instead of choosing a more general color from the Master menu This is

a good way to change the color of the sky from red to pink, for example With a bit

of masking, you could even use it to change the color of an object, such as a car or shirt

6.5 Color Balance Techniques

It's often hard to adjust color balance correctly because one part of the image is lit

by a different color of light than another I'm not talking about changing the color balance of a specific area but correcting all the areas of the image that were lit by a light source of a different color than the main light source Examples of this would

be colors reflected from walls, clothing, or tablecloths Another common example would be a portrait taken by window light The highlights might be lit by daylight and the shadows by the tungsten bulbs lighting the interior

6.5.1 Using a Color Balance Adjustment Layer

The Color Balance adjustment layer is nondestructive, but not all that controllable when it comes to color balancing a specific brightness range in the image You can choose whether the adjustments affect highlights, midtones, or shadows You can also check a Preserve Luminosity box so the brightness range doesn't change as you make your adjustments

In Figure 6-30, I've rebalanced the highlights so that the skin tones are warmer in the highlights, while the rest of the image has retained the original color balance The end result is that the picture looks even more romantic

Figure 6-30 On the right, the Highlights radio button was turned on and the

Yellow slider increased by about 25 percent Notice the warmer tones in the

highlight areas and especially in the models' faces

6.5.2 Using the Curves Adjustment Layer for Color Balance

I don't usually think of Curves as a way to adjust color balance, but you and I both should It's too easy to forget that you can pick a single color channel from the drop-down menu on the Curves dialog and apply the curves to that color This allows you to easily increase or decrease particular ranges of color If your purpose

in changing color balance is to set a different mood, changing small areas of color

in the image can do it It's also a good device for correcting colors in a limited

changing color in two of the channels

6.5.3 Levels Adjustment Layer

The Levels adjustment layer is also a good way to control color in a single channel Again, you just choose the desired channel from the pop-up menu on the Levels dialog box You can also control the range of that color a bit more accurately by moving the Highlight, Shadow, and Midtone sliders to limit the range of colors that will be affected in each channel Figure 6-32 is an example of the sort of fantasy effects that can be created this way

Figure 6-32 In the after image, each color channel was limited to about one-third

of its normal brightness range The adjustments were totally arbitrary

6.5.4 The Auto Commands in Levels

If you followed my recommendations for adjusting the Levels adjustment layer in the Layers Workflow layers by adjusting each of the color channels individually, you have already come pretty close to attaining perfect color balance If you

haven't, I strongly suggest you go to the "Levels for Shadow, Highlight, and

Overall Brightness" section of this chapter There is a quicker way to do this,

which is totally destructive: by using the Auto Color command in the Image

Adjustments menu Of course, nothing in Photoshop is quite what it appears to be and if you look carefully at the Levels dialog you'll see a button labeled Auto The default for this command is to do exactly what Auto Color does by clipping each channel Histogram at its minimum and maximum values In fact, you can easily incorporate that adjustment into the Workflow Layers action so that this button is clicked as soon as the Levels layer is created Now, when you're really in hurry, you'll have all your images auto color corrected Figure 6-33 shows the result of clicking the Auto button using the default Enhance Per Channel options To change the defaults, click the Options button

Figure 6-33 A subtle but dynamic change in the color balance using the

Temperature and Tint sliders in Camera Raw compared to using the Auto button in

a Levels adjustment layer (right)

NOTE

Levels can be used to correct or subjectively change the overall (midtone) tint of the images channel by channel, just as you do when using the Color Balance

command Go back to the individual color channels and drag the midtone sliders

Be sure to have the preview box checked so that you can see the result

6.5.5 When to Use Hue Instead of Color Balance

Since both Hue/Saturation and Color Balance adjustment layers change the overall color balance of the image, you may wonder when to use one instead of the other Use Hue/Saturation when you want to:

 Color balance a CMYK image for fine-tuning output to offset printing

devices (see Chapter 12)

 Create an effect that changes one set of basic colors to another See Figure

6-34 for another example of this

Figure 6-34 An image as it came out of Camera Raw adjustment (left) and using the basic workflow layers in conjunction with the Hue/Saturation adjustment layer (right)

 Change the color balance or a range of colors and add or subtract saturation

 Subdue the effect by lowering the opacity or fill of the adjustment layer