The Use of Chroma Key Technology in the Classroom

Presented by Dean Pomfrett

Wenona School

2009

What is Chroma Key?

Chroma key is often referred to as Green Screen or Blue Screen techniques

Chroma Key allows you to replace the background of a video with any still or moving image of your choice

Chroma Key is a simple yet powerful tool in special effects video making

How does Chroma Key work?

Chroma Key is a function built into certain video editing software

The computer recognises a certain a colour (usually bright blue or green) and makes it ‘see through’

This allows a background image or video to be seen wherever that colour was

This colour is usually

used as a background

Justification to the use of video making in the classroom

Watching films, TV or Video is moving from a very passive activity to an interactive one

Education always keeps up with technology, from early film projectors to television and the internet

Interactivity and control of visual imagery is becoming more natural and even expected by students

One way we can allow creative use of visual imagery is to allow students to create their own videos in the context of the curriculum and the classroom.

Using Chroma Key in the classroom

Chroma Key can be used to enhance any video being made by the students in any KLA at in any stage

To do this, the video must be shot in front of a green (or blue) screen. When editing this video, you tell the computer to replace this green colour with a background of your choice.

Ideas for using Chroma Key

Read stories to the camera as an alternative publishing method

Make a movie or video play

Make a news show – either real or fictional

Present scientific reports in character

Make a documentary on a studied topic eg hiccups

Record election speeches or pledges from school leaders to play back during the year of office to reinforce their commitment

Make simple trick effects like making people disappear

Animations, using drawings or photographs

Make a promotional video for the school

Make a musical video clip – as easy as random ideas edited together with a sound track

Memorabilia clip for an outgoing Year 6 or Year 12

Read a poem with a musical background and drawings inspired by the poetry

Make a simple game show with questions from a studied topic

STEP 1

Set up a green (or blue) background screen, the size you want your background to be.

5 Simple Steps to Chroma Key

STEP 2

Film your subject filling the background with the green/blue screen.

5 Simple Steps to Chroma Key

STEP 3

Import your movie into your computer editing program which contains a chroma-key function.

5 Simple Steps to Chroma Key

Example shown here Pinnacle Studio.

5 Simple Steps to Chroma Key

STEP 4

Determine your background, either moving or still and import this into your computer editing program.

STEP 5

Activate the Chroma-key function on the software and watch the magic begin.

5 Simple Steps to Chroma Key

STEP 5

Activate the Chroma-key function on the software and watch the magic begin.

5 Simple Steps to Chroma Key

Popular programs that support Chroma Key

For PC

Pinnacle Studio

Sony Vegas

Adobe Premiere and Premiere Elements

Corel Video Studio

For Apple

imovie Vers 9

Final Cut Pro and Final Cut Express

Some tips for using Chroma Key

Try to have a smooth as possible colour background with as much even light as possible

More than fill the screen with green/blue because often the viewfinder on the camera doesn’t show complete coverage but the computer will

You can edit in Windows Video Maker then just transfer to a different program for the Chroma Key

Use a tripod (or static camera)

Don’t move the camera while shooting since the background will stay still once edited in Chroma Key

Don’t use the background colour in clothing or props, if this is unavoidable, switch background colours

Final Thoughts

Tapes, discs and memory are now all very cheap… and are re-usable!

Some of the best ideas come out of experimentation.

Remember – Long after the event, the video lives on.