Sony Vegas 5 Manual

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4.Adjust the selection area to change the viewable area of the track and its position in space. Guides are 
displayed in bold to indicate how the track will be moved or rotated: 
5.Use the buttons at the top of the dialog to allow or prevent movement or scaling. For more information, see 
Changing editing options on page 221.
Tip: Right-click the workspace to display a shortcut menu 
that displays commands to restore, center, or flip the selection 
box....

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Composited group 3D motion
1.Click the Make Compositing Child button ( ) on the tracks you want to 
group to create a compositing group. For more information, see Understanding 
the parent/child track relationship on page 214.
2.Click the Parent Composite Mode button ( ) on the parent track and choose 
3D Source Alpha. 
3.Click the Parent Motion button ( ) on the parent track. The Track Motion 
window is displayed.
Parent track motion affects the parent...

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Note: When you have a 2D track in the track list, tracks below 
that track are rendered in 3D and then composited as a 2D image. 
In the following examples, both text tracks have been rotated in 3D. 
In the first example, the two tracks intersect along their rotation 
axis. In the second example, adding a 2D track above the “cool” 
track causes it to be rotated in 3D and composited as a 2D image so 
the “hot” text is displayed above it without...

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Creating masks
Masks are used to create overlays, limit the effects of a filter, and to create transparent titles. In their simplest 
form, masks work by making a particular color in an image or video transparent. More complex effects can be 
created with gradients (smoothly blending transparent areas together) and by altering the sensitivity of the 
mask.
Parent/child video track grouping using the 
Make Compositing Child button is only available in the...

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The effects of the masks are very clear in these examples, but this is not how they would actually be used in a 
real production. Masks are commonly used to isolate a portion of the video from an effect. Masks do not 
need to be black and white, or grayscale, nor do they need to be still images.
Tip: It is best to use images that are the same size as your 
project’s frame size. You may also need to change the pixel 
aspect ratio of an image file to get it...

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Creating video masks
You can also use video files to create masks, although the process can be more complicated than using an 
image as a mask. The key to any mask is contrast. You can increase the difference between the light and dark 
areas of a video file using video effects plug-ins.
1.Insert the video that you want to use as a mask into a video track.
2.Drag a Black and White plug-in from the Video FX window to the event to remove the color. For more...

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Fine-tuning masks
Depending on the source material, creating a clean mask can be a tricky exercise. There are a few tools and 
tricks you can use to fine tune a mask.
Solo the track: Click the 
Solo button ( ) in the track list to isolate the masked track. This allows you to 
concentrate exclusively on the mask.
Toggle effects: Turn individual plug-ins on and off to isolate 
effects in a plug-in chain. Keep in mind that the order of the 
plug-ins in the...

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Using the Mask Generator
The Mask Generator is a plug-in that controls the transparency of events to be used as masks when you use 
events that are not grayscale. Apply the plug-in to an event (or a track) in the same way as any other plug-in: 
just drag-and-drop. The Mask Generator plug-in can be found in the Video FX
 window (from the View 
menu, choose 
Video FX).
The Mask Generator and parent/child video track grouping is only available in the full...

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How the Mask Generator works
The following illustration demonstrates some of the effects of the Mask Generator. The background image is 
the original mask. There are five ellipses on the mask: white, red, green, blue and an invisible alpha channel. 
Note especially the checkered ellipse in the lower left of the mask; this is the alpha channel. You can base 
the alpha channel on a color or define the alpha channel in a graphics program that supports alpha...

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Chroma keying
Chroma keying or bluescreening is a special case of overlay transparency. A color key is a specific color or a 
range of similar colors in an image that are made transparent, allowing a background video to show through. 
The idea is to take a video subject and film it against a solid, uniform background color. It is critical that the 
color be smooth and uniformly lit with no shadows, and that the color chosen for the background not be 
used...