Adobe After Effects Visual Effects and Compositing 1 — Questions and Answers
Question 1: Which After Effects effect is most commonly used to remove a green or blue screen background?
- Keylight (1.2) (Correct answer)
- Luma Matte
- Extract
- Linear Color Key
Correct answer: Keylight (1.2)
Keylight (1.2) is the industry-standard chroma keying plugin included with After Effects.
Question 2: What is a 'Track Matte' in After Effects?
- A layer that controls the transparency of the layer directly below it (Correct answer)
- A motion tracking data file
- A type of adjustment layer
- A mask applied to an effects layer
Correct answer: A layer that controls the transparency of the layer directly below it
A Track Matte uses the luminance or alpha of one layer to determine the transparency of the layer beneath it in the stack.
Question 3: What does the 'Collapse Transformations' switch do for a pre-composed layer?
- Passes the pre-comp's transformations and frame size through to the parent composition (Correct answer)
- Removes all transformations applied to the pre-comp layer
- Collapses the pre-comp into a single flat image
- Disables motion blur on the pre-comp layer
Correct answer: Passes the pre-comp's transformations and frame size through to the parent composition
Collapse Transformations lets the parent comp 'see through' the pre-comp so transformations and frame sizes are inherited correctly.
Question 4: Which blending mode makes black pixels transparent and white pixels fully opaque?
- Screen (Correct answer)
- Multiply
- Overlay
- Hard Light
Correct answer: Screen
Screen blending mode inverts, multiplies, and inverts again, resulting in black areas becoming transparent.
Question 5: What is a 'Pre-composition' (pre-comp) in After Effects?
- A nested composition used as a single layer within another composition (Correct answer)
- A rough draft composition before final rendering
- A composition exported at lower resolution for preview
- A template composition saved for reuse
Correct answer: A nested composition used as a single layer within another composition
Pre-composing groups selected layers into a new composition that appears as a single layer in the original timeline.
Question 6: Which After Effects feature allows you to apply an effect to all layers in a composition without pre-composing?
- Adjustment Layer (Correct answer)
- Guide Layer
- Null Object
- Shape Layer
Correct answer: Adjustment Layer
An Adjustment Layer applies its effects to all layers below it in the composition stack.
Adobe After Effects Visual Effects and Compositing 1
Which After Effects effect is most commonly used to remove a green or blue screen background?