Robert L. Frazier ( )

Remote teaching

Teaching requirements

During Trinity Term 2020 I am doing two types of teaching. The first type is revision sessions for those sitting Final Honour Schools (exams) during the latter half of term. There are two groups of 5-10 attending. The second type is students reading for either Final Honour Schools, or who would have been sitting Preliminary Exams at the end of terms, but are now doing mock exams instead. These are either taught singly or in pairs.

The topics I'm teaching this term are Ethics, Knowledge and Reality (Epistemology and Metaphysics), Philosophy of Science, Philosophy of Science and Social Science, Logic and Language (Philosophical Logic and Philosophy of Language), Frege and the Foundations of Arithmetic, Mill's Utilitarianism and General Philosophy (Introduction). I sometimes use logical notation and sometimes draw pictures.

My hope is to make the teaching as interactive as possible. It isn't the same as face to face tutorials. For example, it is harder to read body language, there are lags in communication, sometimes signals drop, and bandwidth for high quality communications isn't always available. So, it is important to be able to have some communications even if there is signal degradation.


The university has a preference for people using Microsoft Teams, so that's what I'm using. I use linux, so that complicates things. Microsoft provides a client for linux (astonishing, but true). However, it does not have the full capabilities of the Windows client (not so astonishing). In particular, Microsoft's linux client does not allow screen sharing, which is a capability which I find important. Consequently, I'm not using Microsoft's client, but another client, Teams for Linux, which has more capabilities.

For all teaching sessions I use the Teams meeting function. Instead of using the camera directly, I share my screen, or, actually, the contents of one window on my screen. This allows me to manipulate the images, etc., using local tools.

In particular, I use Open Broadcaster Software Studio (OBS Studio) for image manipulation. It allows for the use of a green screen, cropping camera displays, and, most importantly, the easy use of multiple cameras.


Logitech C920 HD

A good basic camera. The field of view is a bit wide for my use, so the image is masked to the size I want. Unfortunately, they seem to be in short supply. Luckily, I had one.

Ipevo VZ-1 HD

This is a specialized webcamera, often used to display documents with a projector. They too seem thin on the ground. Again, I had one. Ipevo website

Lights and stands

Given that I have had an interest in film photography for some time, I had various lights and stands, which have proved useful

Green screen

The green screen is a roll of paper with a standard green colour, bought online. It is hung from stands made from various bits I had to hand. For example, I put an old curtain rail through the cardboard tube about which the paper is rolled, and laid the curtain rail ends on the stands. (Having made little cradles for the rail ends using a bit of junk wood.)

Set up

Here are two pictures of my setup.

Having even lighting is important for using a green screen. So the lights. Also, this is cluttered because it is in the garden room part of our shed, as my study is even less well organized for the use of a green screen.

You can see main camera on the top of the monitor. The document camera is to the side. The monitor show the image from the document camera.

Here is an example of what is displayed when only the main camera is being used. The green in the green screen background is replaced by an image of my choice. In this case, a photograph I took some time ago of the attic of Aston Hall, Aston Villa, Birmingham.

When I use the Ipevo document camera, I leave a small image from the main camera in the top left corner. Here is an example image.

It is easy to switch between views (or "scenes" following OBS Studio use). And, so far, this setup seems to work okay for teaching.


I have no idea whether I will have to do any remote teaching in the future, but, just in case, I thought that I would spend a bit of time tidying up my setup for it. In particular, I wanted a better camera, and better lighting. I replaced the Logitech camera with a GoPro (Hero4). It has a much better lens. I replaced the large and unwieldy lights (which I had for still photography) with 3 12v "birdie" mini spotlights with 4000K leds bulbs, adding 1/4 orange filters and diffusers to soften the light. They are hooked up to dimmers, which allows me to control their brightness individually. Also, the greenscreen is hung from hooks, rather than using stands for it.

Although I am lucky in having a space for remote teaching, it is in a rather cluttered garden building (fancy shed). So, I use a greenscreen to hide the clutter. When using a greenscreen there is a temptation to use some fantasic picture as a background. Although I have given in to this temptation, I think a more subdued background is better. So, using various images, I constructed a virtual background.

It is virtual all the way down, e.g., I combined a picture and a picture of a picture frame to get a picture of a framed picture. I wanted a textured background which isn't too busy but busy enough and dark enough to smooth over inadequacies in the lighting of the green screen. I also wanted to give some visual indicators of depth, which is why I included the pictures on top of the background.


The teaching year is fast approaching. The current information I have about teaching at Christ Church (Oxford University) is that we will be giving tutorials face to face (with masks). However, I suspect that there will be some remote teaching from my office in college, and fear that there will be some remote teaching from home. So, it looks like it would be prudent to have remote teaching/meeting setups in each place. My college setup won't be quite as snazzy as my home setup, but, since I got the GoPro for home, I now have a decent webcam for college (Logitech C920). Unfortunately, I didn't have a second document camera to use as a whiteboard, and Ipevos, although pretty good, are expensive and generally unavailable for purchase.

Consequently, I made a document camera for home. First I bought an inexpensive manual focus, 1080p, webcam and took the camera module out. It had a very wide, "fisheye", lens, so I bought an inexpensive macro lens for it (M12 lens mount, the same mount as the GoPro). I then made a stand for it (from scrap wood) with dimensions centering the camera for A4 paper, at a height which maximizes coverage. The stand is less versatile, but easier to keep adjusted than is the Ipevo's. The aspect ratio of the camera is not the aspect ratio of the paper, so I have unusable margins at the top and bottom (as with the Ipevo). I then used some spare LED strip to make a dimmable light for it. My experience with the Ipevo is that having a uniform light makes all of the difference. Indeed, my general experience with cameras and light is that it is much better to have a mediocre camera and good light than it is to have a good camera and mediocre light.

So, it is a bit kludgy, but it works at least as well, if not better, than the Ipevo, at a cost of less than a quarter of it, not taking into account time spent making it.


I moved from the garden room to the house in the autumn when the weather got cold. Since then I've been gradually changing my setup. I still have three lights, in additional to the standard room lighting. One is over my screen and camera, and one on either side. I generally use them on their lowest settings. I also changed my camera to a Apeman A80 action camera, changing the wide angle lens for one with a narrower field of view. This improves the video quality. I have it on a stand in front of my monitor so I look directly at the camera. Since the background is fine without a green screen, that simplifies things. I also started using a Behringer dynamic microphone on a stand. The microphone is connected to a Solid State Logic audio interface.