Setting Screen Correction - Blackmagic Design Ultimatte 12 Manual De Operaciones

Setting Screen Correction

Screen correction can be helpful if there are strong variations in your backing screen, or the
lighting on the backing screen is uneven.
If your camera is static and you can remove all the foreground objects from the scene, you can
perform a screen correction. This shows Ultimatte what the screen looks like by itself, and then
once all elements are replaced, Ultimatte can then analyze what has changed in the foreground
and will generate an optimized matte. This can help tidy up any areas that are not behaving in
your matte.
To perform a screen correction:
1 Remove all the foreground elements in your scene so only the backing screen is visible.
2 Select the 'matte' settings from the main menu buttons.
3 In the 'groups' section, select 'matte process'.
4 In the functions area, click the 'screen capture' button. This stores a snapshot of the
green screen which Ultimatte uses to generate the screen correction.
5 Now replace all the foreground elements into your scene.
6 Click the 'screen correct' button.
Your Ultimatte will now analyse the foreground elements against the captured image and
determine the optimized matte.
NOTE When using the screen correction feature, it's best to perform this function once
the camera is set and in place, because once the camera moves, screen correction will
no longer be effective and you will need to reapply the screen correction.
Quick Guide to Building a Composite 35