• Wirecast™ Introduction
• Good presentations
• Usage Patterns
• Hardware
• Media Capabilities
• Titling Capabilities
• Logo Capabilities
• Broadcasting
• Editing Encoder Presets
• Desktop Presenter
• Media Management
• Menus
• Preferences
• Main Window
• Shot Editing
• Shot Element Panels
• Edit: Scene
• Edit: Title
• Edit: Media
• Edit: Effects
• Edit: Playback
• Edit: Motion
• Edit: Filter
• Edit: Chroma Key
•   Overview
•   Configuration
•   Getting a good key
• Acknowledgments

In General

Probably the most important part of getting a good key is getting good source material.

Poor source material will generate poor keys; no algorithm can make up for this fact.

The better source material you have the easiest time you'll have dealing with any chroma key system.

Lighting

Assuming a reasonable camera, the most important part of getting a good key is good lighting.

If you buy anything else, buy some good lights and learn to set them up properly.

Here are some basics:

• The background green/blue screen needs to be independently lit from the talent.

• Evenly light the green-screen (no shadows). The more evenly lit, the better.

• Light the talent evenly (no shadows). A fill light is very important (use a white board in an office)

Good Camera

You should be able to get reasonable quality out of most reasonable cameras out there.

We have purposely purchased and tested with a low end DV camera to verify the quality of the key, but of course the better camera you have the better.

A cheap USB Web-cam will not give you enough source quality to get a reasonable key.

If you have excellent lighting, an iSight will work well.

3 CCD is better than 1 CCD, web cams will have poorer quality keying (some are just not usable, others passable, depending on your needs).

If you have the choice, a PAL camera is better than NTSC, due to how data is, internally, captured.

Capture Device Size

In the Advanced preferences, try changing the Capture Device size to "Native"

This gives much more data to the chroma key and allows for a better key, in general.

The trade-off is performance (more data means more to do when keying). But it's generally worth the tradeoff.

NOTE: If you use "Native" you must use Blend for deinterlacing.

High Quality Video

if you are keying video (from disk, not capturing live), you should make sure that this option is checked in the Advanced preferences panel.

This tells Wirecast to decode the video from disk in the best quality possible thus giving the Chroma Key the best data possible to key from.

Wirecast will warn you if High Quality Video is off and you attempt to turn on Chroma Key.