Recording video lectures

This year, I reorganized my undergraduate class “Basic Econometrics” and, for the first time, introduced an online component. For this online component I recorded a number of video lectures. I experimented with different formats that all come with their unique advantages and disadvantages. Here, I give a brief summary of my experience.

Background

The online modules are based on my lectures from previous years. In these lectures, I present the main econometric concepts using a traditional lecture format (“chalk and talk”), supplemented by the occasional slide show. To illustrate the application of these concepts to real data, I sometimes give live demonstrations in a statistical software. To help the students digest the new information, I have planned regular think pair share exercises that challenge them to apply the new concepts in the context of a concrete economic example.

My goal in reorganizing the course was to retain a similar learning experience, while shifting a part of the interaction to the digital realm. After each session of video lectures in the digital classroom, the students will meet me in a physical lecture hall where they will be working on practice problems. In the pedagogical literature, this way of organizing a class is called flipped classroom.

In recording the video lectures, I did not attempt to compete with professionally produced tutorial videos. My goal was to improve the student experiences at a reasonable cost. As such, I expect my experiences to be valuable to other academics who find themselves severely constrained in how much money and - most of all - time they can invest into improving their teaching.

Video format “Powerpoint lecture”

The first video format I tried is the obvious “professor talking in front of Powerpoint slides” format. For these videos, I used the studios (“inspelningsrummen”) that are provided by the pedagogical support unit at my university. Here is an example of this kind of video:

Let me first summarize the advantages of this format:

  • This format is visually appealing and creates the illusion of a somewhat professional production quality. It adheres closely to the expectations that most people have about what video lectures are supposed to look like.
  • The lecturer is featured prominently and body language can be used to keep and focus the attention of the viewer.
  • If a suitable set of slides is available and if one is willing to compromise a little on quality then videos like this one are surprisingly cheap to produce. This assumes that the required recording equipment (green screen, camera, microphone) is available and easy to set up.

The disadvantages are as follows:

  • If, rather than using existing slides, you decide to make brand new ones then the cost of making such a video increases dramatically.
  • A lot of the arguments for why Powerpoint slides are terrible in the classroom hold also in the context of video lectures. The main problem is that Powerpoint, despite its apparent purpose, is a terrible tool for designing helpful visual aids to complement the narration. Making even a very simple diagram is a daunting and time consuming task. What is worse, it is hard not to get swept up in the time honored tradition of adding visual fluff. In the video above, I used a small number of stock pictures, for each of which I had to check carefully that I have the license to use it in my video. This took quite some time, but I doubt that it improved my teaching in any meaningful way.
  • This format requires the lecturer to record longer stretches of video at a time. In a live lecture, the occasional stutter or incomplete sentence are easily forgiven. Recorded and preserved for eternity they can be annoying and it is tempting to rerecord each segment many times in order to get the perfect take. Unless one is ready to embrace imperfection, this will be a substantial time drain. This is particularly true for people like myself who are recording in a language that is not their native language.

Here are some things that I learned while recording these videos:

  • If you work with a green screen and lights that are shining right at you, don’t wear glasses. If you do, removing the color green may also remove a part of your eyes. Also, if you have frizzy hair it is hard to remove all of the color green around your head and you will be wearing a bit of a green halo in the final product.
  • Powerpoint will hide the cursor when showing a presentation on full screen. However, screen capture software will still record the “hidden” cursor and it will show up on your final video.
  • It is easy to get caught up with the visuals and to forget about sound. Make a big poster that says “check microphone” and hang it right next to the camera so that you will be looking at it whenever you record.
  • Before you start recording the lecture, make a short test video to make sure that the camera is capturing your whole body/upper body even as your are moving your arms.
  • In a classroom, jokes are a great way of catching the students’ attention and making the class in general more enjoyable. This does not work on video. At least not in video lectures that the students are expected to revisit multiple times.

Video format “Blackboard drawings”

For the next format, I tried to recreate the blackboard drawings that I use during a lecture to explain concepts and to visualize relationships between different concepts.

I love how natural and easy it is to create drawings that add value by pointing out relationships that are challenging to explain verbally. For example, since speech by its very nature proceeds linearly, it is not well suited to explain, for example, a circular relationship. A simple diagram, in contrast, can easily summarize the idea of a circular relationship.

My goal for this format was to have handwritten notes and drawings appear on the screen as if it was a piece of paper while I’d narrate.

A good (but untested, at least by me) way to achieve this effect is to use software that lets you draw on a touch screen together with a screen capturing software. It seems that, for example, Apple Pencil would be well suited for the job. An ideal setup would allow the lecturer to record their handwriting and narration simultaneously. If visuals and narration are recorded separately then putting them together can amount to a substantial editing effort.

Unfortunately, I did not have access to the hardware and software required to make the approach described above work. Instead I macgyver’d my way through the recording process as follows:

First, I taped a clipboard to my desk. Later, white paper clipped to the clipboard would be my canvas. Then I attached a cheap HD webcam pointing downward at the clipboard to the kind of stand used in chemical labs. To make sure that the camera did not capture the stand itself, I used a three-pronged extension clamp attached perpendicularly to the stand to mount the camera about 20cm away from the stand. Finally, I wrote my notes on white sheets of paper attached to the clipboard. While I wrote my notes, I had the camera take pictures at regular intervals. It turned out that I needed a lot of pictures so I wrote a little terminal script that took pictures and filed them away pretty much automatically. Now that I had pictures of my handwritten notes, I recorded the narration for the lecture. Then I arranged the pictures stop-motion-style into an animation that was synced up perfectly with the narration.

Here is an example the kind of video that I shot this way:

There is a lot I like about this format:

  • It allows me to teach in my preferred way, with the visuals supporting and adding to the narration. This approach allows me to prioritize thinking how I think a concept is best explained. Whenever I use Powerpoint I feel much more restricted and I tend to think first about what kind of things the technology allows me to do and then choose the best option from this restricted set.
  • In this approach, mistakes can be corrected easily and quickly. For example, if I am unhappy with one sentence in the narration it is easy to swap out only this one sentence. This is in contrast to the “Powerpoint lecture” approach where I would have to reshoot whole segments. Also, you can go a long way toward avoiding mistakes in the first place. For the video above I recorded the audio in short segments of about 30 seconds. Between recording segments, I gave myself a few seconds to think about what I wanted to say next. If you are uncomfortable with talking freely you may even draft the narration first and then read it off your screen.
  • Since this format is fairly close to how I teach in a lecture hall I was able to build on my old lecture notes and I did not have to rethink the pedagogical concept from scratch.

The following disadvantages are of note:

  • Compared to videos in which you can see the lecturer talking, this format makes it a little harder to keep the viewer’s attention. Firstly, this is because the disembodied voice that is doing the narration is lacking the body language and facial expression that guide us through normal conversation. Secondly, my “stop motion” approach divorces the pacing of the film from the pacing of the recording process. This can lead to the video lecture having an “unnatural rhythm”.
  • The final product is functional but it is not shiny. This will matter differently to different people. Arguing to care or not care about this is essentially revisiting the debate whether to teach in a t-shirt or dress primly and properly.

The process I chose to record these videos may seem a little convoluted but it worked surprisingly well. I spent quite some time on editing the videos but the recording process itself didn’t take a lot of time. The time I spent on preparation before I started recording went 100% into improving the didactic quality of the video.

In a way, the “Powerpoint lecture” format is the exact opposite. The Powerpoint lectures take a while to record since most segments have to be reshot multiple times but require very little editing. Making the slides can take a lot of time, which is spent mostly on working around the restrictions imposed by the software and resolving licensing issues for media used in the video.

Other formats

In addition to the formats described in detail above, I also used some other formats.

For example, I demonstrated calculations that I do in my computer by capturing my screen. Here is an example, where I embedded demonstration in Excel inside the “blackboard drawing” format.

Before I got access to the recording studio, I recorded some Powerpoint lectures in my office using the built-in camera in my Macbook.

Considering that the “Powerpoint lecture” and the “blackboard drawing” formats have contrasting strengths and weaknesses, it is natural to consider combining them into a hybrid approach in a way that offsets their respective drawbacks. This would probably result in lectures of superior quality but it would greatly increase the cost of producing the videos. It is something that I would not consider attempting unless I had a generous teaching grant supporting the endeavor.