[Mara flipping through a book at the kitchen bar, Joanne enters the room with a cup of coffee.]
Joanne: What's up Mara, you seem a little sad?
Mara: Yeah, I just wish I could go hiking on a mountain or rock climbing or watching the Northern Lights with Poppy and Icey but no I'm stuck in a house with nothing to do.
Joanne: I know it's tough, so on today's episode of ask me anything science edition we're gonna talk about how you can go on those adventures without even leaving your living room. Like this.
[Joanne snaps fingers.]
[Video cut to Mara conducting an orchestra. She snaps the baton.]
[Scene changes to her climbing on a mountain.]
[Scene changes to her warped body in a black and yellow spiral. A loud buzzing sound.]
[Video cuts back to kitchen bar.]
Joanne: All you need is a camera, a couple of big solid-coloured sheets and some video editing skills.
Mara: I really don't have video editing skills.
Joanne: Don't worry, that's not that hard and we'll get to that in a bit but first we need to set up our green screen.
Mara: I was wondering what all that poster board was for...
Joanne: Yeah I picked it up at the dollar store, for a dollar piece before we started physical distancing. Are you ready? Hold my coffee!
[Video cuts to sped up scene of Mara and Joanne taping green poster board to the wall.]
[Cut back to sitting at the kitchen bar.]
Mara: I still don't get how it ends up looking like this....
[Finger snaps. Mara is floating cross legged in front of a tree in the sunshine.]
[Cut back to the kitchen bar.]
Joanne: All right well let's do a quick clip of you playing the guitar in front of the green screen and then in our editing we can take out the green, make it disappear and put in whatever background we want.
[Cut to Mara playing the guitar in front of the green screen. She strums and the crowd appears and screams!]
Mara: Wahooo!
[Cut back to the kitchen bar.]
Mara: That's so cool! How about flying now!
Joanne: What's the magic word?
Mara: ABRACADBRA!
[Joanne shakes her head.]
Pleeeeeeeease!
Joanne: You got it.
[Joanne snaps her fingers.]
[Cut to Mara on the green screen in a Super Man flying position. Background changes to sky!]
[Cut back to kitchen bar.]
Mara: How does that work exactly?
Joanne: Good question. So when you open up your video editing software look for something that says colour key or chroma key. I use WeVideo here.
[Split screen with kitchen bar scene at the bottom and screen share of WeVideo on top.]
So when I open up the colour key tab there's a little eyedropper symbol... use that to select a region of the video that's green and then the software knows to make any part that is that colour disappear. It's just that simple.
[Cut to full screen video editor.]
[Cut to full screen back at the kitchen bar.]
Mara: Cool! That just leaves me behind and you see the other video clip you added in as my background.
Joanne: YUP! And lighting is really important you don't want any shadows, so our homemade setup isn't perfect but it's not bad really.
Mara: Awesome! Ok can we do one more because I always wanted to see the Northern Lights.
Joanne: Let's do it! To the Northern Lights!
[Cut to Mara in front of the green screen holding two polar bear stuffies. She looks around in wonder. ]
Mara: Okay just one more question, why do we use green screen instead of like yellow.
Joanne: Well it doesn't have to be green um you just need a solid colour that's all one colour. But it's good to choose a fairly unique colour so that parts of you don't disappear when you do the colour key technique and make sure your clothes don't match either because they'll disappear too kind of like an animal blending in with its surroundings
with camouflage.
[Cut to video of an octopus on bending in with the sea floor.]
[Cut back to kitchen bar.]
Joanne: This is what happened when we tried a navy-blue sheet.
[Cut to Mara on a box covered with a navy sheet and navy sheet in the background. Underwater bubbling noises.]
[Background changes to underwater.]
[Cuts back to both at the kitchen bar.]
Mara: That's not as good but not bad for an old sheet!
OK, now you guys try it in your kitchen or in your living room and make sure to share your videos with us on Facebook or on Instagram.
Joanne: Have fun and keep those questions coming.
Mara: Thanks for watching Ask Me Anything Science Edition.
[Monster roar]
Mara: Uh oh! GOTTA GO!
[Monsters roars and fleeing screams of people while super cool guy snarls at camera.]
Are you and your junior scientist feeling the strain of quarantine? Did you realize that adventure was only a few sheets of green cardboard away? Join 3M National Teaching Fellowship recipient Dr. Joanne O'Meara and Mara as they explain how green screens work!