Technical Fix Effects


When you think of video effects, technical fixes do not come to mind. The primary reason you use video effects is to alter the appearance of your video clips ”to blur, emboss, tint, or distort ”or to add graphic elements, such as fire, clouds, lightning, lens flare, and film "noise."

So I'll get this mundane technical stuff out of the way first.

With one exception ”Levels ”you probably will not tap Premiere's technical fix video effects all that often. They typically come into play only for very specific, narrowly defined needs.

I'll introduce my top pick, list the technical fix effects with brief explanations , and then go over how to use my top pick.

My Favorite Technical Fix Effect: Levels

The Levels effect is a Jack-of-all-trades that manipulates the brightness, contrast, and colors of a clip. It has four basic functions:

Color Balance ” You will use this time and time again. No matter how carefully you use white balance, some video clips will turn out too blue, or red, or green. The Levels effect lets you fix that by adjusting the individual RGB color values. (Note that the QuickTime RGB Balance effect interface is more user friendly than this Levels effect's color balance.)

Gamma Correction ” Anyone's who's played a video game with a too-dark setting knows that bringing up the gamma levels brightens the scene without washing it out. This effect accomplishes that by bringing up the mid-tones while leaving dark and light areas unaffected.

Brightness & Contrast ” This is standard TV control stuff that can significantly enhance your video.

Invert ” This switches color information. The Invert effect in the Color Appearance category does a much better job. Use it instead.

Using the Levels Effect

Drag the Levels effect (in the Adjust file folder) to a video clip. It pops up the Levels Settings dialog box, shown in Figure 12.2.

Figure 12.2. The Levels Settings dialog box is not immediately intuitive.

This is not your father's TV set brightness and contrast control. The interface takes some explanation. The chart is a histogram of your currently selected frame. Brightness values from dark to light run along the X-axis. The Y-axis represents the number of pixels at each brightness value.

Use the drop-down menu to choose whether you want the tonal adjustments to apply to one of the three color channels or all three at once.

The sliders right below the histogram control contrast and gamma. Drag the black triangle to the right to increase the shadows, the white triangle to the left to increase the highlights, and the gray triangle to control the gamma ”the mid-tones.

The Output Levels slider reduces contrast. Dragging the black triangle to the right eliminates the darkest values in the clip, whereas sliding the white triangle to the left eliminates the brightest values.

You can save your settings and then load them later to ensure a consistent look to your altered clips.

Other Technical Fixes

Here is a list of the other technical fix effects that are available to you:

Broadcast Colors ” This effect ensures color values will play back on PAL or NTSC TVs. It's a powerful tool with simple controls, but you may never need to use it.

Clip ” Trims away noise from the edges of your videos , replacing the removed pixels with a user-specified frame color. It's not likely you'll want to have such a frame, so use the motion/shape settings to zoom your video to push noisy frame edges offscreen .

Field Interpolate ” Rarely used. It's for instances when field loss (basically, half a video frame) occurs during capture.

Median ” Median's strength is its oil painting effect (see Color Appearance). But its original purpose was to reduce video noise.

Reduce Interface Flicker ” Very thin horizontal lines sometimes lead to disruptive flicker on some TVs. This seeks out those trouble spots and softens their edges to reduce flickering .

The following technical fix effects are redundant. Feel free to put them in your Duplicates folder: Brightness & Contrast, Color Balance, Crop, Gamma Correction, and Resize.



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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