Studio shots of a speaker alongside or interspersed with images, graphics, or videos are among the most effective devices for delivering online content. Most of the best educational videos use this method. The speaker provides the information, while the images illustrate it. The speaker grabs our attention, while other content amplifies it. See this exceptional example from the online course Learning How to Learn: http://bit.ly/1LNbRwA.
Such videos are created using greenscreening, the method that TV weather forecasters use to interact with a weather map. The actual background in the studio is a blank screen of a vibrant color that will not be used elsewhere in the video. Fluorescent green is the most common because it is unlikely to be worn by the person in front of the camera and is easy for the software to distinguish from other colors. The shot is taken with an ordinary video camera, but during editing the screen color is removed using a process known as chroma keying. The editor simply picks out the color that is to be removed and tells the software to replace it with whatever else is desired.
Online course can use greenscreening in a variety of ways, most commonly for delivering course content. Hip Hughes History is an excellent series of YouTube videos created by a high school teacher who uses the method to teach a variety of different topics in history. See an example at https://youtu.be/yXo9tRB4S3E. Students can also make videos that explain a concept, quiz the viewer, and provide an account of a historical event, among other things. I have seen people set up models and figurines to shoot animated videos while inserting different backgrounds using greenscreening.
Greenscreen videos are common in MOOCs, but most faculty members assume that they are too technical to be done for the average institutional course. In reality, the process is surprisingly simple, and teachers are making these videos at all levels of education and in all fields. It is common for students to make greenscreen videos in the K–12 realm. With a few pointers, you can make greenscreen videos for your courses.
Shooting a greenscreen video
It is likely that your film, photography, or marketing department has a greenscreen studio, so the first step is just asking around to see if a studio is already set up at your institution. If not, then you can easily make your own. The screen itself can be purchased online from B & H Photo for around $60. When choosing a screen, make sure it is big enough to cover not only the subject you are shooting, but also whatever you want to put in on the sides. Screens also come in different materials. While fabric is the cheapest and can be easily folded up when not in use, it is also the easiest to wrinkle, and wrinkles will produce shadows on the screen that may not come out in the video. So it might be worth paying a bit more for a wrinkle-resistant screen. You can hang whatever you get with PVC piping at the top and bottom to pull it flat. If you have a permanent place to shoot your videos, you might want to consider painting a wall with Behr's Gamma Sector Green Disney Color paint, available at Home Depot and designed for greenscreen shooting.
Next, make sure that your subject is well lit. The goal is to remove all shadows. The ceiling lights in a classroom might be sufficient, but if not, start by having a light in front and on both sides of the subject that cross to remove shadows. You will also likely need a second set of lights behind the subject focused on the screen itself to remove shadows created by the subject. Another good idea is to put a light above and behind the subject facing forward. This will create a nice white outline around the subject, rather than the harsher black border that is often produced without it. See a good video of greenscreen hints from TechEducator here at https://youtu.be/J-1gxuLIHGo.
Because the video used for greenscreening is no different from ordinary video, any digital camera can shoot it. But you should use something with high definition because the blurriness of low definition is distracting. Even a good webcam such as a Logitech C930 HD 1080p will work. You definitely want to put the camera on a tripod to eliminate shaking. The small area of the shot means that the subject is not going to move around, so the camera can be fixed in place. The video editor will use panning during the editing process to reposition the subject in the frame when any elements are added on either side. You might also want to turn off the autofocus on the camera and instead set the focus manually so that it does not try to focus on the screen, rather than the subject.
Finally, it is critical to get your audio right, as people will quickly turn off anything with poor sound quality. Hang a sign on the door of the room where you are shooting to warn people to not knock or walk in. Plus, make sure to watch for the hum of air conditioners or heating vents. As for the microphone, a good camera-mounted microphone will work, but better sound quality can be obtained from something closer to the subject, either a handheld microphone, or better yet, a lapel microphone.
Understand that you will likely shoot a number of takes before you get a clean version, so try not to get frustrated. It will take time. You can use cue cards for notes, but unless you have a teleprompter, you don't want to write out the speaker's narration word for word because it will be obvious that the speaker is reading from a script off to the side. Just put a few notes on the cards in outline form and use them like you would use notes in class.
A central tenet of shooting videos is to show enthusiasm. Most people get nervous when being recorded, and they slow down their speech and employ a monotone. This makes you look bored, which will caused your viewer to get bored. Watch any good educational video series on YouTube, and you will see a lot of enthusiasm. Remember that the content is interesting and meaningful, so demonstrate that in your manner and voice.
Greenscreening requires video editing software that comes with chroma key functionality. One of the cheapest and easiest to use is Do Ink, a $5 iPad app. With Do Ink, you can use the iPad both to shoot and edit the video afterward, providing an all-in-one option. The app is simple to use and produces decent quality at a low price. See this video on how it works: https://youtu.be/LWAHxtpPp24.
TouchCast is another iPad app that I covered in a previous issue (October 2014). TouchCast allows you to make videos with interactive pop-up elements such as documents, webpages, quizzes, and Twitter feeds inside the video frame. It comes with chroma key functionality and offers an $80 “Studio in a Box” setup with a greenscreen, lapel mic, iPhone and iPad holders, and miniature tripods to shoot your videos. See www.touchcast.com/studioinabox.
iMovie for Mac also comes with chroma key functionality, as does Camtasia Studio, which I use for all of my video editing because of its many functions. This video on how to use chroma key editing in Camtasia Studio has helpful production tips and covers processes that apply to most video editors: www.techsmith.com/tutorial-camtasia-8-remove-color.html.
Finally, if you can get your instructional designers or film department to help, they will probably already use a higher-quality video editing system such as Adobe Premier or After Affects, both of which come with chroma key functionality. I find that these people are generally chomping at the bit to show off their video editing expertise when asked, so you might be able to get someone else to do all of the editing for you.
Consider greenscreening as a fun and easy way to add exciting videos to your online course.
Tech Educator Podcast. 2013. Everything You Have Wanted to Learn about Green Screens, Lighting, Cameras |TechEducator Podcast, YouTube video, 1:03:01, posted by Jeffrey Bradbury, August 11, 2013. https://youtube.com/watch?v=J-1gxuLIHGo
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