To Set Up a Chroma Key in Basic Mode

Tip: Once you have set up the chroma key how you want it to appear, you can press and hold CHROMA KEY and press the KEY MEM button to store these settings and the key source. Pressing the KEY MEM button again will recall these settings for the chroma key.
  1. Press the SEL button on the Keyers module for the key you want to set up and select a video source on the Key bus.
    Tip: The SEL button allows you to quickly select the keyer you want to work with and assign the Key bus to the keyer. On the Double-Down control panel, the top button row is assigned to the even numbered keyers (2,4,6,8) and the button row below is assigned to the odd numbered keyers (1,3,5,7). This can be changed with the DD Key Delegation personality option.
  2. Press CHROMA KEY.
  3. Use the Key Mode knob to select Basic.
  4. Use the Color knob select the color you want to key out. This is the background color of your Chroma Key that will be replaced.

    From the Personality menu, you can change the default color that UltraChrome uses.

  5. Press Initialize Key.
    Note: Every time the key is initialized, the switcher resets all the Chroma Key parameters to their default settings.
  6. Press Background and use the Gain knob to adjust the background gain.
    • Increasing the gain value causes the background to appear more opaque. This results in less of the background color being removed.
    • Decreasing the gain value causes the background to appear more transparent. This results in more of the background color being removed.
  7. Press Foreground and use the Clip, Hue, and Reject knobs to adjust the colors used in the foreground image.
    • Clip — adds or removes lower-saturated colors from the foreground image.
    • Hue — select the central, or base, color for the foreground image. Increasing the hue value moves counter-clockwise around the color wheel, and decreasing the Hue value moves clockwise around the color wheel.
    • Reject — include or reject hues adjacent to the base color. Increasing the reject value decreases the amount of adjacent hues that are included in the foreground and decreasing the reject value increases the amount of adjacent hues that are included.
    Figure 1. Effects of Clip, Hue, and Reject
  8. Press Spill Suppress and use the Range knob to adjust the amount of background color that is spilling over into the foreground (green color cast on the foreground from a green screen for example).
    • Increasing the range value causes more of the foreground colors to be corrected for background color spill.
    • Decreasing the range value causes fewer of the foreground colors to be corrected for background color spill.
  9. Press Edge Softness and use the Softness, Width, and Additive Keying knobs to adjust the edges of the foreground.
    Note: Edge softness is not available if the chroma key is being used by a floating DVE key.
    Note: If the Width adjustment is set greater than Off, the Sensitivity is automatically set to Low. The Sensitivity is set back to what it was before when Width is set back to Off.
    Tip: The default Width and Additive Keying settings can be adjusted using the UltraChrome Dflt Width setting on the Personality menu.
    • Softness — add or remove edge softening of the foreground image and alpha channel. Increasing the softness value increases the amount of softness applied to the foreground edges and alpha channel. Decreasing the softness value decreases the amount of softness applied to the foreground edges and alpha channel.
    • Width — adjust the outside edge of the foreground image and alpha channel. Increasing the width value increases the amount that the key encroaches onto the foreground image. Decreasing the width value decreases the amount that the key encroaches onto the foreground image.
    • Additive Keying — set the edge sensitivity.
      • Off — reduce the level of detail in the edges of the chroma key. This option will reduce the overall noise in the key image that can be the result of certain lighting conditions or high detail camera settings.
      • On — include the maximum detail in the edges of the chroma key.