Professional Information Technology-Programming Book part 39 potx

When you place the same knockout into a target image, you can do that same thing, but this time pick up the color from the layer that will be the background image.. Open the image you wa

Regardless of the technique used, if the surface of what you knockout is even

slightly reflective, you will probably have some traces of the original background color around the edges This reflected color is easily eliminated Choose the Brush tool and choose Color from the Options bar's Mode menu Go to the Layers palette and click the Lock Transparency icon Press Opt/Alt to momentarily convert the Brush to an Eyedropper and click in an untinted portion of the item to pick up its color Now, just brush over the reflected color from the old background When you place the same knockout into a target image, you can do that same thing, but this time pick up the color from the layer that will be the background image You can see the result of the re-coloring in Figure 9-10

Figure 9-10 This cutout was made with the help of one of the Frames Custom Shape tools You could also use Layer Style to bevel the edges of shapes and to cast shadows

9.3.3.2 Using the Extract filter

The images that are really tough to knockout are those that are in a complex

background, have highly irregular edges (flying hair), or very soft edges (semi-transparent or blurs) Fortunately, Photoshop 7+ comes with a tool called the

Extract filter, which improves with every new edition of Photoshop It's not the most sophisticated of the knockout tools, but you don't have to pay extra for it And most of the time, with a little practice, you can do a credible job of making the knockout The lady with the hula-hoop in Figure 9-11 was knocked out with the Extract filter Figure 9-12 shows you the original image and the resultant knockout

To do this:

Figure 9-11 The subject was knocked out with the Extract filter

Figure 9-12 The Extract dialog box

1 Open the image you want to knockout and immediately choose Image

Duplicate There's no hot-key for this, so make yourself an Action to do this and then assign that Action a hot-key that you're not using for anything else

You should always duplicate any image that you're going to do very

destructive things to so that you can use the messed-up image as a layer without destroying the original

2 Since the Extract tool won't extract from the background layer of an image,

in the Layers palette, double-click the background layer of the duplicated image When the New Layer dialog appears, enter knockout and the subject name as the name of the new layer

3 Make sure the Knockout layer is still selected and then choose Filter

Extract The Extract dialog shown in Figure 9-12 appears Double-click the Zoom tool to make the preview window show the image at full (1:1)

resolution

4 Choose the Highlighter tool (aka the marker) and make the brush size large enough to cover the flying hair while keeping one-third or less of the marker color inside the portion of the image that should be kept You should always follow this one-third rule when selecting "transitional" (fuzzy or fly-away) edges Pan around so that you cover all those transitional edges first Once you've done that, make the brush size just large enough (press the square bracket keys: [ to get a smaller brush and ] to make it larger) to cover any slightly fuzzy edges and check the Smart Highlighting box

5 Choose Gray Matte from the Display Menu in the Preview Options This will temporarily place a neutral gray background behind the preview image

so that you can more easily see what edge corrections need to be made

6 Choose the Fill (bucket) tool and click inside the Highlighter selection It will fill with blue If the blue fills the entire image, you have a space in your Marker selection Simply zoom in to 1:1, press the spacebar to pan, and pan around until you find the gap(s) Then use the Marker to fill them in Then use the Fill tool again Repeat until only the area inside the marker is filled with blue

7 Click the Preview button You will see Figure 9-13, which clearly shows the goofs made by the Marker selection You can either try a new Marker

selection or use the cleanup tools The cleanup tools are those that have a tool in front of a Mask icon The Brush cleanup tool erases edges with some intelligence Press Opt/Alt to make it replace instead of erase The Marker cleanup tool smooths and cleans up edges It either does a great job or really messes things up If it's the latter, quickly press Cmd/Ctrl-Z to undo and use the Brush cleanup tool

Figure 9-13 Extract in Preview mode, so you can easily see what needs cleaning up

When you're cleaning up edges, it really helps to switch background colors Then you can see all the colors that need cleaning up, whereas grays may not

be visible against gray, etc

8 Once you've finished your cleanup, click the OK button You see the result

in the righthand image in Figure 9-11

Third-Party Compositing Tools

There are a couple of tools that make parts of the compositing process

much easier

The first tool, onOne Mask Pro, originally made by Extensis, was

recently acquired by onOne Mask Pro is a third-party plug-in for

Photoshop that does quite a good job of knocking out both smooth and

fuzzy-edged images Available for both Mac (Universal code yet to

come) and PC at a reasonable $199.95, it is quite versatile for its price If

you've lit the background evenly enough and in such a way as to

minimize reflections, you can knockout almost anything in a totally

realistic way

There are two main tools for designating what should be kept and what

should be thrown away: Marker and Eyedropper The Eyedropper tool is

best used when you have a plain-colored background You simply click

the three or four most different shades in the background and foreground

You then use a Magic Brush tool to remove all the colors that should be

thrown out It's an excellent tool for removing a colored background

from a portrait or a furry animal You can see in Figure 9-14 how well it

separated the teen model's hair from the background The beauty of this

technique is that, because you don't brush inside the object to be kept,

there's no chance of knocking out details that are the same color as the

background

Figure 9-14 The onOne Mask Pro interface showing a portrait that is

being knocked out with the Eyedropper and Magic Brush tools

The Marker tool works best when you have a complex background and

object that contain many colors It's similar to the technique used in the

Extract tool Use the Green Marker to designate the area to be deleted

and the Orange Marker to designate the area that will be kept You then

use the Magic Bucket to click in the area that will be knocked out As

you can see in the toolbox in Figure 9-14, there are also numerous tools

for cleanup To find out more, go to www.ononesoftware.com

The second tool is Ultimatte AdvantEdge, which is designed strictly for

removing matte green and matte blue (aka green screen and blue screen)

backgrounds You have to shoot in a studio to use these backgrounds

The other piece of bad news is the cost of this plug-in: $1,495 That's

roughly twice the price of Photoshop CS2 at full retail Yet an amazing

number of pros buy this package Why? Because it does a perfect or

near-perfect job of knocking out even the most complex images from

their backgrounds Furthermore, you can do it in seconds Pretty much

all you have to do is open the image you want to knock out in the

plug-in, click once on the background, click a button telling the program to

process, and then watch for a miracle To find out more, go to

9.3.3.3 Using the Select Color command

When you want to knockout a solid color background but you're having trouble getting exactly what you want from the programs mentioned above, give the Select Color command a try It's right in Photoshop and won't cost you a penny extra The main secret to getting what you want is learning how to judge the setting of the Fuzziness slider Find a photograph that has been taken against a reasonably solid color background and open it in Photoshop Then:

1 Choose Select Color Range The Color range dialog, shown in Figure

9-15, will appear

Figure 9-15 You can see that the main portion of the selection is well

defined, although you'll want to use Quick Mask Mode after the selection is made to "paint over" details inside the selection that you don't want selected

2 Choose the method of color selection you want to use from the Select menu

I don't have room to show you that menu here, but your choices are:

Sampled Colors; any of the primary RGB colors or their complements, highlights, midtones, or shadows; and Out of Gamut For making knockouts

from solid color backgrounds or taking out monotone skies, the best choice

is usually Sampled Colors

3 Choose Quick Mask from the Selection Preview menu You'll now be able

to see exactly what is selected when you drag the Fuzziness slider You'll also see the orange quick mask superimposed over your image

4 If, in the preview window, you still see areas of color that haven't been

selected, choose the + Eyedropper and click on those colors until everything you want is selected

5 Drag the Fuzziness slider as far to the right as you can without letting the Quick Mask cover any of the image that you want to knock out The most important thing is to get the edges right You can always fix the Quick Mask after the fact, as I'll show you in a second

6 When you have the Fuzziness and the selected colors just right, click the OK button

7 You'll see a selection marquee appear on your image You will probably want to mask some of the interior details in this selection, so click the Quick Mask icon in the Toolbox The orange mask will re-appear on the image Press D to make sure your foreground color is pure black and the

background colors is pure white

8 Choose the Brush tool and set its Opacity at 100 percent and its Blend Mode

to Normal and paint over any interior details that aren't fully masked If the image you're masking is as geometric as our example, you can just make a selection inside its boundaries the then choose Edit Fill Black In Figure 9-16, you can see what the fully masked image looks like in Quick Mask mode and what the resulting knockout looks like

Figure 9-16 Using Quick Mask mode to knock out this building

9 Save your knockout, duplicate it, and drag the duplicate into a layer in your composite image