To Key or Not to Key
(Yes that’s the question.)
We all have an idea of “The News at 8”: the anchors at their desks in front of floating video screens and weather forecasters flailing wildly over maps (“LIGHTNING TONIGHT FOLKS STAY INSIDE, look for sun tomorrow”). I’m sure many of us truly believed that there was just some giant map in some giant warehouse that they were gesturing (giantly) in front of. Or somebody had invented some floating tv screens (and didn’t tell us about it, how dare). The unfortunate truth, however, is that they went to work every day and stared at a boring green wall (sometimes blue).
Do you really need the power of the key?
The technology of keying (chroma keying), masking and “using the green screen” is an incredibly complex monster of a subject, so the important place to start is the question: “Do I really need to use keying to begin with?” Sure, putting the subject (or yourself) in fantasy studio or background is a fascinating idea, but for the most part, designing, aligning, color correcting and keying may use up more time, energy and sanity than you have left after the edit itself. Just filming yourself in a cool little studio could save you some time and brain power (decorating the barn out back? you bet).
“Look ma, I’m Godzilla”
Okay, let’s say we DO need to key the subject out. Maybe for some cool graphic effects. Maybe to put them into outer space. Perhaps they just need this one little object out of the center of the frame. So what should we do next?
Chroma Key Me Up, Scotty
It’s a bird, it’s a plane, it’s… carl.
Chroma keying is the process of isolating a subject by removal of a specific color, i.e. Green / Blue screen. It can be your best bet for scenes that require the subject to be placed in a different world or difficult situations (i.e. superman flying through the air). There are entire studios dedicated to this technique to ensure that the keying process goes smoothly in the edit (or you can end up with some tricky footage and hours of time will be spent
crying over a computer fixing small errors here and there).
Keying with green screen can still be achieved without these bigger setups, but takes a lot of pre-production and planning for optimum green screenage.
Bullied by the english language since 550 CE
Alternative Keying Methods
“We don’t have a green screen available to us, but we would like to have some floating text behind the subject.” Good news, everyone!
There are a few options besides enlisting the power of chroma key that still may get the job done.
Can you make this person in the iphone video stand on top of this tower?
Although a green screen is nearly essential for placing subjects in a different space, some alternative methods are available in a few different programs (my go-to being Adobe After Effects). Some of those options are:
- Luma Key (the process of removing subject/background based on the Luma of the image)
- Masks/ Rotoscope (manually masking out your subject from the background)
- Mattes (layers that use the lighter/darker areas of footage to define the transparency of that footage to use over another layer)
Each of these alternatives can take a lot longer than the typical chroma key process, so it’s good to keep in mind when planning your video deadlines.
I dunno, seems like a lot of work
Bottom line: Do you really need to sit on Uranus
Although ‘movie magic’ is the jam (see: Vibing Cat Meme.gif) and is useful for a lot of big budget films and news station media, it’s not really ideal for every day social videos. The time it takes to remove the I </3 Mornings coffee mug they forgot about behind them may take just as long (or longer) to edit out versus just filming another take. While both of these aren’t ideal, when doing simple iphone/social videos, it may be a better option.
Of course… it pays to plan ahead to get the shot done right the first time :winkwink: