Color Appearance Effects


Color Appearance Effects

Okay, we've got the boring stuff out of the way, now for the toys.

In Hour 11, "Creating Video Effects," I demonstrated several color appearance effects, including Black & White, Crystallize, and Replicate. Some make your video look like a painting. Others shift pixels or delay their display creating embossed or ghosting effects.

The 15 QuickTime video effects handle several of the color appearance effects. Some QuickTime effects are bettermore controls, better options, or improved output qualitybut most are simply on par with their Premiere cousins. Because the QuickTime effect is so accessible and can replace so many Premiere effects within one consistent interface, I suggest that you "hide" duplicate Premiere video effects and use QuickTime instead. One caveat: you cannot keyframe QuickTime effects.

I've created subcategories to clarify differences within the Color Appearance category. All but the duplicates and one color appearance effectColor Embossfall into my Favorites collection.

Color Appearance Painting Effects

All four of my favorite painting effects are very easy to apply. You can use keyframes for all but Facet. I covered three of them in Hour 11, so I'll simply present visual examples of those effects in Figures 12.312.5 and explain the fourth, Median, following those figures.

Figure 12.3. Crystallize creates a mosaic of colored irregular polygons.

Figure 12.5. Pointillize gives your clips that Seurat look.

Figure 12.4. Facet is a subtle effect that smoothes video into what appears to be a soft oil painting.

Median

The Median effect replaces pixels with the median value of neighboring pixels. A radius of one or two pixels reduces noise (see the discussion of technical fixes), but at about five pixels a video gets a nice soft-focus painting feel to it.

I'm guessing that of these four effects, the one you have not taken a look at yet is Median. It's tucked away in the Image Control file folder.

Try Median out by applying it to a clip. Note that the Radius slider, shown in Figure 12.6, goes only to 10, but you can type in higher values. The higher the number, the softer the focus. Try a value of 40. Because you can use keyframes, you can change this effect over time.

Figure 12.6. The Median effect's Radius slider creates a soft-focus painting look.

Color Appearance Color-Manipulation Effects

I'll explain how to use all three of these color-manipulation favorites after the following brief explanations :

Color Pass You've seen those advertisements where one color stands out. This is how they do it. Color Pass converts a clip to grayscale (black and white), with the exception of one color.

Color Replace This effect lets you select a color and then replace it with another. Both this, and Color Pass can be tricky and need some planning to pull off well.

Extract This effect converts a clip to grayscale and lets you manipulate its appearancefrom soft to harsh .

Color Pass is a super-slick effect that requires some careful pre-production preparation. To do it right, you need to create a setting where the object you want to highlight is a distinctly different color and evenly lit. Painting your object a color such as lime green will make it much easier to isolate with Color Pass later. Once it's converted, you can apply Color Replace to the same clip to alter that horrible lime green color into something more palatable.


Task: Use the Color Pass Effect

To use the Color Pass effect, follow these steps:

  1. Drag Color Pass from the Image Control folder to a video clip. Select Setup to open the Color Pass Settings dialog box, shown in Figure 12.7.

    Figure 12.7. The Color Pass Settings dialog box's Eyedropper tool lets you select a color to highlight.

  2. Move the cursor into the image on the left, and it turns into an Eyedropper tool. Use it to select a color from that frame or click the color swatch to select a color from the standard Premiere color spectrum box.

  3. Move the Similarity slider to adjust the "range" of the color you're going to highlight, using the right screen to find the "sweet spot." Clicking Reverse "grays out" that selected color and retains all others.

Color Pass and a few other video effects' Settings dialog boxes display only the first frame of the selected video clip. Even if you've created a thumbnail/poster frame marker, the Color Pass Settings dialog box still displays the first frame. To see how changing the effect values impacts a particular frame, you'll need to move the edit line to that frame and then make your fixes in the Effect Controls palette, not the effect's Settings dialog box. The changes will show up on that frame in the Program Monitor screen.


Task: Combine the Color Pass and Color Replace Effects

To combine the Color Pass and Color Replace effects, follow these steps:

  1. Keep Color Pass switched onthe f is in the check boxin the Effect Controls palette.

  2. Drag Color Replace to the Effect Controls palette. Click Setup to open the Color Replace Settings dialog box, as shown in Figure 12.8. The image in the left window should be gray, with the exception of the color you selected in Color Pass.

    Figure 12.8. The Color Replace effect lets you select a color and replace it with any other color.

  3. Use the Eyedropper tool to select that color; then select a replacement color from the color spectrum window. Now you see how they do those cool TV spots.

Using the Extract Effect

Clear the Effect Controls palette and drag in Extract from the Adjust folder. Its interface, shown in Figure 12.9, gives you full control over the clip's grayscale, giving your clip a textured, solarized, or standard black-and-white look.

Figure 12.9. The Extract effect gives you a wide range of grayscale possibilities.

The two triangles below the histogram set the range of pixels converted to white or black. Extract converts pixels between the triangles to white; those outside the triangle become black. Softness adds levels of gray to the white pixels. Invert swaps white with black, creating a negative, X-ray look.

Color Appearance Color Shift Effects

Slightly altering or shifting some color characteristics can create dramatic visual effects. The following five video effects fall into this catchall subcategory :

Alpha Glow This effect provides a very slick way to give a graphic a glowing fringe or shadow by adding color around its edges. I'll explain it in detail later.

Color Emboss This is the one color appearance effect that does not appeal to me. It's supposed to give elements within a clip a full-color embossed look, but it just seems to scramble colors haphazardly. I've illustrated it in Figure 12.10. The sliders set the characteristics of the embossed effect.

Figure 12.10. The Color Emboss effect.

As you can see in Figure 12.10, there is no "setup" option in the Effect Controls palette for Color Emboss. Color Emboss is an After Effects (AE) effect, and all AE effects work only from the Effect Controls palette. In Hour 13 I'll go over my favorite AE effects.


Emboss This effect does in fact create embossed images. It offers more readily accessible controls than the Emboss element within the Convolution Kernel effect (see Blur/Sharpen, later). You'll find it in the Stylize folder. As Figure 12.11 demonstrates , Emboss has sliders similar to Color Emboss. Because the Emboss "Blend With" slider lets you add color to your image while making very distinct embossed edges, you can use it to create both black-and-white and color embossed effects.

Figure 12.11. The Emboss effect creates very distinct embossed effectsblack and white or color.

Ghosting This is a nifty effect where pre-production planning can be a big help. It creates ghost-like "comet trails" behind anything that moves. It works great if you hold the camera really steady while something moves through the scene. You may have given it a trial run in Hour 11.

Invert This multifunction color shifter lets you substitute inverse RGB (Red, Green, Blue) color information, HLS (Hue, Lightness, Saturation), and YIQ (NTSC luminance and chrominance values). It works much more easily than the Levels effect version. The Effect Controls palette's options are deceptively simple. Use the drop-down menu, shown in Figure 12.12, to adjust those elements by their group type or individually.

Figure 12.12. The Invert effect creates something like a film negative with the ability to limit those changes to specific color or luminance data.

The Alpha Glow effect introduces something called an alpha channel . This typically is a characteristic of graphics created in programs such as Adobe Photoshop, Illustrator, and After Effects. An alpha channel is the portion of the graphic that you can make transparent or translucent. I'll go over how to use alpha channelsas well as other transparency processesin Hour 14, "Compositing Part 1: Layering Images and Clips," and Hour 15, "Compositing Part 2: Alpha Channels and Mattes."


Task: Use the Alpha Glow Effect

To see the Alpha Glow effect work its magic, follow these steps:

  1. Start by adding a graphic with an alpha channel (see the preceding note) to your project. You can find one Veloman.eps in Premiere's Sample folder.

  2. Drag Veloman.eps (or your own graphic) to the Video 2 track directly above any other clip. You use Video 2 or a higher track because you're going to superimpose this clip over another clip.

  3. In the Effect Controls palette, select Transparency Setup. That pops up the Transparency Settings dialog box, shown in Figure 12.13. I'll go over this dialog box in more detail in Hours 14 and 15.

    Figure 12.13. Use the Transparency Settings dialog box to switch on a graphic's transparent alpha channel. The page peel icon lets you see the clip below the graphic in the timeline.

  4. In the Key type drop-down menu, select Alpha Channel.

  5. Take a look at the image in the upper-right corner. Select the page peel iconI've highlighted it in Figure 12.13and note how that makes the white portion of the graphic become transparent, letting the video clip below your graphic in the timeline appear under the graphic.

  6. Click OK.

  7. Drag the Alpha Glow effect to the Effect Controls palette for your graphic and select Setup. That pops up the Alpha Glow Settings dialog box shown in Figure 12.14.

    Figure 12.14. The Alpha Glow Settings dialog box.

  8. Give the various sliders a test drive. Try this with Fade out on and off, plus add a second color to the glow's edge using the End Color check box.

  9. When you're done, click OK and check out your handiwork in the Program Monitor screen. You should see your graphicwith its Alpha Glow effectsuperimposed over your video clip.

The Alpha Glow Settings dialog box displays only the graphic, not the video clip beneath it. Only after you click OK can you see in the Program Monitor screen how the colors and other elements you selected "work" with that clip. On the other hand, if you make the changes to Alpha Glow from within the Effect Controls palette, as shown in Figure 12.15, you get immediate feedback, but fewer controls are displayed. Neither approach is an elegant solution.

Figure 12.15. Alpha Glow displays fewer options in the Effect Controls palette, but you do get immediate feedback as you make changes.


My Favorite Color Appearance Special Effects

My guess is that you will come to use each of the following three video effects, which create their own unique and nifty visual impact:

Lens Flare Most of the time you shoot your scenes trying to avoid lens flare. This lets you add that refraction to a scene. It works well for slow camera moves. If you use keyframes, you can add it gradually and adjust its location over time as your camera moves by the sun or other light source. As illustrated in Figure 12.16, clicking the scene adds crosshairs to place the flare. Select from three "lens types" and use the slider to change their brightness.

Figure 12.16. The Lens Flare effect coupled with keyframes lets you insert a flare, change its brightness, and alter its location.

Replicate You may have tried this effect in Hour 11. Use Replicate to evenly divide the screen. The minimum setting is four rectanglestwo by two. Maximum is 16 by 16. Each mini-screen displays the entire original clip.

Tiles This effect slices your clip into jittery tiles, sort of like a mosaic in motion. As illustrated in Figure 12.17, the Tiles Settings in the Effect Controls palette let you select the number of tiles per column and how much space can be between them. You fill that space with black (background color), white (foreground color), the inverse of the original image, or the image itself.

Figure 12.17. The Tiles effect slices your image into shaking squares.

The Tiles effect works well as a transparency, letting whatever is below it on the timeline show through the spaces between the moving tiles. I explain how to do this in Hour 15.


Duplicate Color Appearance Effects

QuickTime performs the following five effects as well or better (with the caveat that you cannot apply keyframes to QuickTime effects): Solarize, Posterize, Tint, Black & White, and Color Balance HLS.

Color Offset, although not technically a duplicate effect, fails to perform as designed. Its purpose is to create 3D images to use with red/blue 3D goggles, but I don't think it provides a practical means to accomplish that. Feel free to put all six of these effects in your Duplicates folder.



Sams Teach Yourself Adobe Premiere 6.5 in 24 Hours
Sams Teach Yourself Premiere 6.5 in 24 Hours
ISBN: 0672324288
EAN: 2147483647
Year: 2002
Pages: 249

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