Green screen, that cool method you can use to put yourself or another person in a completely different video or still photography background -- on top of the Empire State Building with King Kong or surfing in Hawaii, for example -- used to be a very complicated process available only to video professionals. You had to have a specially made green-colored scrim mounted behind your subject, set up proper green screen lighting on the person,and then a skilled editor had to key out the green background and replace it with that surf footage (or whatever). Well, now anyone can do this - even live in programs like Zoom. Technology has come a long way, but it’s important to keep in mind that despite this, depending on the platform, the quality of the green screen you create can range from “Wow” to “Meh”.
In this article, we’ll look at how you can put your subject anywhere using the “Green/Blue Screen” effect in iMovie directly on your phone for short videos.
To begin, record your subject against a green or blue backdrop that fills the screen behind them. Yep, that’s right your green screen doesn’t need to be green. Blue works too.* Whichever you choose, just make sure that 1) the screen isn’t the same color as your subject and 2) your subject isn’t so close to the screen that they will cast shadows on it. If you don’t get #1 right, your subject will disappear into the background. And any shadows will ruin the effect and your green screen might not entirely disappear.
Finally, to ensure that the effect works properly, make sure that your green (or blue) backdrop is evenly lit. You don’t want to have really bright spots or really dark spots or iMovie won’t be able to properly replace your green screen with your background - like this:
Once you’ve recorded your subject on your phone, open iMovie. Go through the steps to create a new project - if you need some help doing that, check out our VIDGURU DIY series. When you’re asked to import your video files, select the file that you want to have as your background: Eiffel Tower, Sea of Tranquility, Downtown Gotham, whatever.
Next, move your playhead so it is where you want your green screen clip to begin - at least roughly since you’ll be able to edit the clip after you bring it in. Then go back to your video library by pressing the ‘+’ button on the left.
Select the video you recorded of your subject against the green/blue screen and press the ‘...’ - this will open up a new window that allows you to select the ‘Green/Blue Screen’ effect.
** When you select this, the video will be placed on top of the other video you selected to use as your background. And voila, your subject is in front of the WORLD!
If the effect is there but not quite strong enough (i.e. you can see some of the green or blue from the original background), you can increase the strength by toggling the green icon at the upper right corner of the viewer window.
Toggle strength of the green screen using the tool in the upper righthand corner of the viewer.
That’s all there is to it. You have now created a green screen effect just using your phone!
And with that, I look forward to seeing you on Mars!
*Note: If you ended up not using a green or blue backdrop, then you’ll be prompted to select the color in your video that you would like iMovie to remove. I’ve found that this works some of the time, but more often than not little pieces of the video you wanted to see get swallowed up by the software, or other parts you didn’t want to see get left in and the effect doesn’t really work.