Performing A Chroma Key - Blackmagicdesign ATEM Mini Installation And Operation Manual

Performing a Chroma Key

ATEM Mini features an advanced chroma keyer with detailed chroma sampling and adjustment
options. These controls help you achieve the best key, improving the blend of foreground and
background so you can create a more convincing visual effect.
To set up a convincing chroma key using the advanced keyer:
1
In ATEM Software Control, expand the upstream key palette and select 'chroma' from
the key types bar.
2 Select the fill source. Typically, this source would be from a camera facing a presenter
in front of a green screen, or a graphic loaded in a media player.
3 Click the 'chroma sample' button. With the chroma sample selected, you'll see a new
panel appear with a box cursor. This cursor is also visible on the preview output.
4 Click and drag on the box cursor to move it to the position you want to sample.
The chroma sample setting lets you position a cursor over the screen area you want to sample
Choose a representative area of your green screen that covers as much of the luminance range
of the screen as possible. The default size of the box cursor is well suited to most green
screens that are relatively evenly lit, however if there is a lot of variance in your green screen,
you can adjust the size of the box by clicking on the slider to the right of the sample window
and dragging it up or down.
TIP When sampling uneven green screens, we recommend sampling the darkest
area first before increasing the size of the sample box. This can give you a more
accurate key.
NOTE You can preview your key on the preview output via HDMI at any time by
clicking the 'preview' button above the chroma sample panel. This shows you the final
composited version of your chroma key effect on the preview.
Keying using ATEM Mini 95