When shooting against a backdrop, it can be challenging to make your footage appear professional if you only have access to a small setup. Unless you zoom in to get a medium or close-up shot, chances are you’ll see the edge of the backdrop. This completely eliminates getting a true wide angle of your subject, and can break the illusion of a professional setup, which can severely distract your audience. In such situations, there is a way to extend the backdrop in After Effects to get the look of a big studio that easily captures the full space around your subject. The best part is that it’s easier than you might think! So let’s dive in and get started!
The first thing you need to do is ensure is that your footage is captured with a flat backdrop. This means that there are very few shadows being cast on the back and, if there are any, that they are soft and subtle. Additionally, you want to make sure that no part of your subject’s body exits the framing of your backdrop, and any additional space between it and the edge is beneficial. Finally, your backdrop need to be a solid color, or at the very least containing only a soft gradient. Any pattern or distinguishing features will be easily displayed when we stretch out the edge of the backdrop.
Stretching Your Backdrop In After Effects
Now is the time when we dive into After Effects. When we look at our footage it looks very ammiteur, being able to see the edges of our backdrop. The entire illusion is broken. So what we’re going to do is extend the backdrop of what’s already present so that it covers the full screen.
The first part of getting this effect is to mask around the entirety of your subject. Go through the entirety of your footage and make sure that your mask doesn’t cross over where your subject waves their arms or moves out of the box. You can track or keyframe this mask if you’d like, but you don’t need the mask to be perfect for this effect to work, so a basic shape surrounding them is all you need.
Now duplicate your layer, and I'm just going to hide the top layer from being visible for a second. on the bottom layer, delete the mask. Now unhide the top layer and what we have is one layer is for showing your subject, and the other layer is for everything else. To make things easier, let’s name our top clip “subject”, and our bottom clip “background.”
What you can do next is duplicate the bottom layer again 2 more times, labelling each background 2 and 3 automatically. What we’re going to do is mask an area to the right (or left) of the subject in a rectangle and take as much as we can that's just the background and also not cutting into our subject's body at all. Then make sure that the anchor point is on the side closest to our subject. When you move the anchor point it actually moves the whole mask and it’s off from where it was. We need it to be exactly where our footage originally was otherwise it won’t look right. But thankfully we simply input the new anchor point value into our horizontal position, and that will bring our footage back exactly to where we were originally.
What we’re going to do now is go down to the transform options, uncheck uniform scaling, and drag the first value (which is horizontal scaling) and extend it to the edge of our frame. The reason we moved our anchor point was so that now when we move the scale our footage scales from our anchor point and we don’t have to move again to line it back up.
Now to finish it all off, let’s add a very subtle mask feather. I’m going to go with a value of 5. And when we reactivate the other layers, we can see that our backdrop is now extended all the way to the edge of the frame.
Now we can take that same idea and apply it to the other side. Let’s go through exactly the same process of masking the area, moving the anchor point, matching the position, adding a feather, and extending it out.
Why Use This Method?
Now let’s quickly answer a question that might come up. Why wouldn’t you just add a solid background and try to match the color as close as possible?
This is answered with two reasons. The first is that even the most evenly lit backdrop will have some minor variation in shadowing and gradation that you won’t consciously pick up on but will be noticeable if you try to replace sections with one consistent color. Because we extended what already existed, we also don’t get get any duplicating patterns with the very subtle shadow elements in the backdrop. It feels like one complete unit.
The other reason is that, in our example, you can see very subtle and soft shadows of our subjects movement around their feet. This isn’t a big flashy thing, but it helps to sell the effect that the room is bigger than it is. If the shadows were harsher, and you very carefully studied them, you might be able to tell that they’re stretched shadows and aren't behaving as normal. But when they are soft or subtle, there’s no way for you to tell that it’s not the way shadows would normally act in the space you’re filming in. And because there’s shadows being cast over manipulated elements (in a subtle way) it gives the impression that the entire area is properly interacting with the subject. Pretty cool right?
Now let’s finish it up by doing the same thing we did on the left and right of our subject, only this time for the top. The steps are the same, only dealing with the vertical elements rather than horizontal ones.
Once that’s complete, let’s color correct your footage. I’m going to go and grab the lumetri color effect from our effects tab, and then drop it onto our footage. I’m just going to adjust the white balance so the backdrop is the correct white shade. Then I’m going to increase the exposure and do some minor adjustments with the curves.
By this stage of the process, you’ve officially done it. You don’t need a crazy huge studio to make it look like you're in one. Just a simple paper backdrop is all you need.
Thank you so much for watching, and I hope to see you in the next video!!!
Music Provided By Motion Array: