By the end of this article, we will have created our own mini weather forecast! We’ll have a weatherperson on screen on the left side of a pre-created weather scene with a few animated weather icons that you can download as a part of the resource pack below.
Note that this will be updated with video and images when possible.
If you’d like to follow along, you should have Alight Motion and all seminar assets on your device before starting.
If you’d rather follow along with a finished project, import the following project into Alight Motion with the link below.
Completed Element Link: http://alight.link/mtxomNkGWFWcLNnP6
About Chroma Key
Chroma key is an effect that allows you to take a group of similar colours and render them transparent. It’s often used to isolate an object in a video, in movies to take a character and transport them to faraway lands, or on the TV news to tell you your local forecast for the next week in a more animated, visual way.
Setting Up Your Film Environment
In order to use chroma key effectively, we need two things. We need a video or image that will serve as our background, in this case our weather map, and we need a video of our subject, in this case our weatherperson. We can make our background in Alight Motion, but for our weatherperson, we’ll need to film them in person. To do so, we need to make sure we film them in a way that will allow chroma key to work well.
For filming our weatherperson, having a green screen large enough to fill the entire background behind them is ideal. If you don’t have a green screen, you can also use a wall, as long as it is fairly uniform in shape, a single, solid, bright color, and colored differently from the subject or anything they’re wearing. Green and blue are usually the best choices, as red/pink/brown/orange can be similar to skin tones, and white/grey/black don’t work well with the chroma key in general.
Once you have your location, it is important to light it uniformly behind your subject. Any shadows on your background may change the color significantly enough for it to not be recognized well in chroma key, leading to lower quality results. Multiple light sources are better than one, and if you have any way to diffuse the light, to make it softer, this will help to avoid any harsh shadows.
The following video has a lot of good tips that can be translated into almost any budget or style: https://www.youtube.com/watch?v=H413prVuG5E
The weatherperson should be as far away as possible from the green screen, as light bouncing off of the green screen may cause green fringing around them, and they may cast a shadow on the screen. At this point the weatherperson needs to be lit as well. Since we’re setting up for a weather forecast, we do not need any special lighting, but know that you may have to set up your lighting differently depending on the lighting in the shot you intend to use as your background, so you can match it as closely as possible. A ring light can really help with this depending on your set up. They’re available for larger cameras as well as cell phones and will evenly light the subject’s face or body depending on the size.
Since we’re going to be putting most of our graphics on the right, we should make sure that our weatherperson stays on the left side of the screen, while referring to the graphics that will be placed on the right.
Using Chroma Key Effectively
Now that you have everything ready it’s time to put together out weather forecast scene. Let’s open Alight Motion and make a new project. We’re going to choose 16:9 for our project size, and leave everything else the same. Tap create to move to the main project interface.
Let’s take our lovely sky scene as our video backdrop. To add this to your project, tap +, then Media, and swipe to search for the sky scene. Tapping on the thumbnail of the video will add it to our project. The video should fit full screen, but if it doesn’t, you can use your fingers on the preview to adjust the size and positioning.
Now let’s add our green screen video. Tap +, then tap Media and select the green screen video of the weatherperson. Adding this to our project should cover the sky video. If it doesn’t, tap on the video layer on the timeline from the far right side of the screen and drag it to the top of the timeline.
Our green screen doesn’t cover the screen, so we will have to do some masking. Without anything selected on the timeline, tap +, then Shape, then add choose a rectangle. Resize and reposition the rectangle so that it stays in the green area, but covers the weatherperson completely. Tap anywhere on the timeline to deselect it, and then long tap on the tab to the left of the rectangle layer on the timeline until it highlights, and then tap the tab next to the weatherperson video layer on the timeline. Tap the three vertical dots on the top right of the screen, then choose Create Masking Group. The visible portion of the video layer will be restricted to the weatherperson and green screen!
Tap on the green screen video layer, then tap Effects, Add Effect, and swipe to Chroma Key. Depending on the color of your background, you may see it immediately disappear, but if it doesn’t, in the Chroma Key effect panel, tap the color swatch in Key Color and use the color picker to choose the correct color. Use the threshold slider to remove fringing from your weatherperson. If you’ve set up your shot well, you should be able to remove the fringing without removing the weatherperson themselves. You can use Feather as well to blur the fringe, which may help the effect in some cases.
If with these two videos, you are experiencing lag, even with the “Low Quality Preview” option in Setting turned on, export these two as is, and start a new project before adding graphics.
Add Your Custom Graphics As Elements
At this point you should have a weatherperson talking in front of a partially cloudy sky. Let’s add some graphics on the right side of the screen to liven up our scene. In the three day forecast video we have provided, it’ll be sunny and 25°C today (Friday), windy and 18°C tomorrow, and 22°C with thunderstorms all day Sunday. In the resource pack link above, we have provided elements for this project.
All of the graphics were created in Alight Motion and have been saved as elements. They are accessible by tapping +, then Elements and choosing the desired element. Elements are reusable pieces of content that you can mostly set and forget. In this case, we have four different elements to use. We have one text element, used for temperature and the days of the week, and one graphical element each to represent sunny, windy, and story weather. The weather elements can be simply placed and resized. The text elements can be edited by taping Element Properties and simply changing the text.
Before adding elements, let’s move the playhead to the beginning of the project so everything we add will start at the beginning as well. Then, let’s put the weather elements in a horizontal line on the right side of the screen. We’ll just place them in, but you could add some in animation if you’d like!
Let’s then place a copy of the text element below and above each element. The ones below will be temperature, and we can change them to match the weatherperson, 25°C, 18°C, and 22°C respectively. The ones above can be changed to Fri, Sat, and Sun respectively.
With that, we’ve created a short weekend weather forecast with a chroma keyed weatherperson and some animated graphics. At this point, we can export to share our video with social media or to our gallery.