Professional Information Technology-Programming Book part 25 pps

If you're not yet familiar with adjustment layers, you'll find them listed on a menu that appears after clicking the New Adjustment Layer icon at the bottom of the Layers palette or by c

6.2 Adjustment Layer Advantages

You probably already understand this, but an adjustment layer actually doesn't make any changes to the layers below it It simply gives Photoshop CS2

instructions on how the image should look and print Adjustment layers have the further advantage of being readjustable at any time, as long as you haven't merged

or flattened their layers (which you should only do when you duplicate the image and flatten it to purposely send an unmodifiable version to someone outside your company or personal domain)

If you're not yet familiar with adjustment layers, you'll find them listed on a menu that appears after clicking the New Adjustment Layer icon at the bottom of the Layers palette or by choosing Layer New Adjustment Layer The adjustment commands that are available on adjustment layers use exactly the same dialog as their Image Adjustments menu counterparts So if you know how to adjust without an adjustment layer, you also know how to adjust with one.Table 6-1 shows the specific adjustments that are available as adjustment layers

Table 6-1 Table 6-1 Available adjustment layer options

The adjustments in Table 6-2 are available only as destructive adjustments, which I'll show you how to apply in a nondestructive way in Chapter 11

Table 6-2 Table 6-2 Available destructive adjustments

Table 6-2 Table 6-2 Available destructive adjustments

NOTE

All of the routines in this section assume that you have run the basic Workflow Layers Action described in the "The Magic Action for Layered Workflow" section

in Chapter 5 If you skipped that chapter, jump back before going on

What follows is an example of how each adjustment layer type might be

particularly useful in a circumstance commonly encountered by professional

photographers (remember, you don't have to be a pro to learn how to think like one) Whereas Chapter 5 described each layer's function, this chapter gives you the most practical applications for each adjustment layer And this time, the layers are more or less in order of frequency of use I say more or less because no two

photographers' requirements are exactly the same In fact, some of these commands may never be a part of your style Still, it's good to know what your options are

6.2.1 Levels Adjustment

Levels is the best command for ensuring that you have a full range of tones in your image However, I have to give you a bit of a warning here: a maximum range of tones is not always best suited for every purpose I have known photographers to make a career of styling their photos to have a unique look by forcing a very

limited range of colors On the other hand, the best artists are usually trained to create technically perfect art, so they know exactly why they are deviating End of lecture

The Levels command is also often used for setting white balance There are a

couple commonly used ways that should definitely be a part of your routine

6.2.1.1 Setting technically correct white balance

You will need some part of the photo to be absolutely neutral in color A grayscale card, black tires, or bleached coffee filters are all good candidates These have to

be the real colors of the neutral object Don't try using a Photoshop technique to

make them that colorit won't work Figure 6-6 shows the difference between the original image and the way it looks after this process

Figure 6-6 The image as it was when opened and then after correcting white balance in Levels using the White Balance Eyedropperfirst on the coffee filter to set white balance, then on the gray card to set exposure

Applying Adjustment Layers to Multiple Images

Since all of the adjustments in this chapter are targeted at all the image

layers below the adjustment layer(s), you can easily apply these

adjustments to multiple images Prepare the first image in the series Then, open half a dozen or so of the other images in the series at the same time

by selecting them in Bridge and double-clicking If they are Camera Raw

files, I'm assuming that you've already followed the instructions for

applying the same Camera Raw adjustments to all the images in the series

(see the "Tweaking Camera Raw Adjustments in Sync" section in Chapter

4) I'll show you the routine for applying the Levels and Curves layers that

are created by the Workflow Layers Action If you've also created others

for a particular group of images, just include them in the same Layers

group

Follow these instructions for applying adjustments to the series of images

you want to adjust:

1 Group all the adjusted layers into an Overall Adjustments Group

2 Open as many other images in the series as Photoshop can handle,

given the configuration of your computer and memory You should

be able to open at least six at a time

3 Keep the image you first adjusted and its Layers palette visible

Drag the other images into a stack on the right side of your screen

4 Select the first image to make it active, and drag the Overall

Adjustments Group onto the image at the top of the stack on the

right If you kept the Layers palette visible, you'll see the group

appear in that image's palette, and the appearance of the image will

instantly change to match the adjustment of the first image

5 Click the Minimize Icon for the image you just dragged the Group

to so that it will be temporarily out of the way

6 Click the first image to activate its Layers palette, and drag that

same group to the next image at the top of the stack Repeat Steps 6

and 7 until all the images (other than the first one) have had the

Overall Adjustments Group added to their Layers palettes

7 Maximize the images one at a time that you added the Group to,

press Cmd/Ctrl-S to save it, and then click its Close icon Don't

close the first adjusted image until you apply the Group to any of

the other images in the same series that haven't been opened yet

8 Open another six or so images and repeat Steps 48, if there are more

images in the series

NOTE

If you already set white balance properly in Camera Raw, you don't need to do this Follow these steps:

1 Select the Levels adjustment layer (If you grouped it, you'll have to open the Group to select it To open the Group, click the small gray arrow to the left of the Group folder in the Layers palette.)

2 Double-click the Levels icon

3 Choose the Set Gray Point dropper and click on the neutral-tone object I have to tell you one more time: the "neutral tone" had really better be totally lacking in color tint and be absolute gray, regardless how light or dark

Otherwise, your white balance will be surprisingly incorrect, rather than correct

4 Adjust the midtone slider to the appropriate brightness level, if necessary

If you didn't have time to include a gray or color card and there is nothing in the image that is absolutely neutral, there's still a process that ensures you have

maximum brightness range from each color channel, as well as overall brightness range The result is usually surprisingly good color balance and a much richer image than you might otherwise have expected All of which make it a good idea

to use this process on any image that you haven't been able to color balance with a gray or color card Figure 6-7 shows the before and after result of applying this process to one image

Figure 6-7 The image as it was shot and then after color correction in Levels by using each color channel Grayscale and white cards weren't used at all to make these adjustments

Follow these steps to correct the color as shown in Figure 6-7:

1 Open the image from Bridge If it's a RAW image, do the best you can in Camera Raw first

2 Go to the Layers palette and double-click the Levels icon in the Overall Levels layer The Levels dialog opens Do not make any adjustments in the composite (RGB) channel just yet

3 Press Cmd/Ctrl-1 You are now in the Red channel If the Histogram

"mountain" touches ground on either end before it touches the end of the base, drag the slider on that end until it touches the base

If the Histogram also touches ground before the other end, drag that slider until it touches the base Figure 6-8 shows how the sliders should look Do not move the midtone slider for any of the color channels at this point

Figure 6-8 The Histogram in one color channel of the Levels dialog

showing the sliders adjusted as recommended

4 Repeat the color channel adjustment you just made for the Red channel for the Green (Cmd/Ctrl-2) and Blue (Cmd/Ctrl-3) channels, in that order

5 Make the adjustment for overall brightness and contrast Press Cmd/Ctrl-~ (tilde) to get to the RGB channel Adjust the Highlight and Shadow channels

in the same way as you did in the previous steps

6 Adjust the overall midtone brightness Drag the Midtone (center) slider until you like the overall brightness of the image Normally, this is where you're done However, sometimes you want to make some further subjective

judgments to the overall brightness range and color balance If that's the case for the image you're currently working on:

a To change the color balance, go to the channel that contains the color you most want to change Drag the Midtone slider to the right to intensify the primary color or to the left to intensify the

complementary color For the Red channel, the complementary color

is Cyan For the Green channel, it's Magenta For the Blue channel, it's Yellow

b To change overall contrast, go back to the RGB channel and spread the distance between Highlight and Shadow to lower contrast or decrease the distance between Highlight and Shadow to increase the contrast

6.2.2 Curves Adjustment

I can usually improve an image by changing the contrast within a chosen range of