Chat Show Format for Live-from-the-Classroom Events?

Frankly set, ABC TV, 2022

Recently I attended a recording of ABC TV's Frankly chat show. This got me thinking that the same studio layout, and format, could be used for hybrid delivery of learning. Frankly uses a standard chat show format: the host sits stage left, with space for four guests beside them. There is a flat area in front for a couple of rows of small tables for audience members who will appear in reaction shots. The rest of the audience are in theatre seating behind. ABC TV use movable cameras with operators. For education we could make do with fixed, voice operated cameras, preset on the presenter positions, and audience.

This room setup would combine features of the flexible flat floor classroom, with those of a traditional lecture theatre. It could be implemented by removing some rows of seating in a fixed lecture theatre, and more easily in rooms with retractable seating, by partial retraction, leaving enough space for tables. The idea is to provide a more interactive up-front (literally) experience for those students who want it, while those who prefer to sit back can. It will also provide a more lively experience for students participating online in real time, and those watching the recording later.

Desktop smartphone holder for webinars

As a backup for my desktop computer during webinars, I put my smartphone in a $10 car-cradle. This has a suction cup I stuck to a CD case, to make a desktop stand. This works remarkably well with Zoom or Microsoft Teams. For additional reliability, the audio for the conference can be via a phone call, rather than the Internet.  

Provide Eye Contact to Enhance Video-conference Engagement?

Brucks, and Levav (2022) have found that people were significantly less productive via video conference, than at a face to face meeting. That may sound like common sense, but this was a carefully conducted experiment, under controlled conditions, measuring productivity. The researchers also tracked the eye movements of participants and were able to provide a plausible explanation for the loss of productivity:  participants online  were not able to engage in eye contact. Previous research found that the eye-contact is an important part of communication. This may explain some of the awkwardness in video conferences, with participants talking over each other.

However, while F2F may be preferable, it is not always possible. When then COVID-19 pandemic struck I was unable to attend the usual symposia and conferences with colleagues. Videoconferencing was the least worst alternative. In one case it has worked very very well. Each week I have been attending the ASCILITE Mobile Learning Sig, and have ended up writing a series of papers over the last two years with a group of people who I have never met face to face. Of course this is a group of people who are experts in online communicaiton. 

I was surprised the Brucks, and Levav  did not go on to suggest technical fixes for this problem. One would be carefully positioning the cameras and video displays, so that the geometry of a face to face meeting could be matched. This approach is used in some high end corporate  video-conference rooms. Each room has the same geometry, with the same meeting table, camera and a large video screen up against one side. The aim is to have the remote participants appear life size, sitting at extension of the table in the same room. An example is Webex's Room Panorama Immersive Telepresence.

Another way to provide realistic eye contact would be to manipulate the image to modify the geometry. This feature could be added to video conference software, in a similar way to cat filters, and artificial backgrounds. The software would identify the participants face in the video, and distort the image so it appears they are looking at the other party. A less processor intensive approach would be with a setup utility which would indicate where the camera and screen should be located, for best effect.

Reference

Brucks, M.S., Levav, J. Virtual communication curbs creative idea generation. Nature (2022). https://doi.org/10.1038/s41586-022-04643-y

Fluorescent Green Screen Version 3

Unhappy with the finish with fluorescent poster paint on my green screen for a virtual Zoom background, I decided to go back to using wall paint. Previously I did not find anyone in a paint shop in Canberra who knew what "chroma key green" was. But Bunnings Belconnen in Canberra had no problem. They selected "Chroma Key Green" from the Dulux corporate colors library, and made from a 250 ml sample pot of British Paints Extra Deep (tinted DD 0Y 43 SS 0Y 5). For the other side of the screen I used Taubmans "Hi-C Blue" (no mixing required).

Web Camera with Zoom Lens for Zoom

Recently I upgraded my home office with a web camera featuring a zoom lens and manual focus. This allows adjusting the image to just include me, without having to move the camera. I selected one with a 720P HD sensor (although they are also available with full HD). The lens is a modest 2.8-12mm zoom, suitable for use on a desktop. For something like a lecture theater, a higher power zoom might be needed. 

The camera sensor is housed in a very rugged, small black metal box, with a standard camera mount thread on both the top and bottom. The lens has screws to lock the focus and zoom in place once set. This is not a camera for live action, as it is difficult to focus, but one you set up, lock in place and leave. The camera has a USB plug, and operates as any other web camera. Similar products are offered on Amazon.

When the COVID-19 pandemic stuck last year I had to set up my home office for teaching by video-conference. However, I decided I should not have anything out of reach of a typical teacher, or student, as education should be accessible to everyone. So I used a low cost, low speed broadband connection, a modestly priced laptop, and a consumer grade web camera. This worked fine, especially with Zoom. However, I decided it was time for an upgrade.

Fluorescent Green Screen for Virtual Zoom Background

Fluorescent Green Screen

I have repainted my Folding Green Screen with bright green fluorescent paint, for better virtual background contrast. Due to COVID-19 restrictions, I was unable to get to the hardware store for paint, so used poster paint instead.  

Image added to green screen

The poster paint is half the price, but produced a less smooth finish than the interior water based house paint I used previously. Fortunately the imperfections don't show up when the virtual background is added. The paint looks much brighter, and yellower, than it does in the photograph. Dark lines where the panels of the folding screen join are masked by Zoom's algorithm, but any light shining though the gaps show up. 

Smart Phone for Video Conference in India

Greetings from the King & Wood Mallesons' International Arbitration Webinar on India. Amanda Lees is chairing the session. I am not a lawyer, but I thought it might be useful to learn a little about the Indian legal system, as I might be asked to design courses for institutions there. 

KWM are using WebEx for the webinar. This is not my favorite video conference system, but it works well on a smartphone. So I have my 4 Inch Android smartphone held in a clamp which came with one tripod, screwed to the desktop tripod from a light. I am listening, so I have no microphone plugged in. 

Hand holding the phone makes for wobbly video and a phone on a desk is too low to give a good angle. A tripod with clamp holds the phone securely at a good height. It is still possible to pick up the whole unit, if necessary, and move it to another location.

When WebEx started, it offered to call me for the sound, so I accepted this option. One bonus of this is that if you receive a phone call, the conference audio is put on hold, so there is no risk of the conference participants listening in on my phone call.

Hybrid Learning Happening

I took part in my first hybrid lecture at The Australian National University, for computing students yesterday. This went okay with 10 students in the room, and 70 online. It was a bit tricky with four presenters, three in the room and one remote, for two hours. A further complication was that the resolution of the laptop used for Zoom was too high to connect to the room projector. You would think a stack of computer people would be able to sort that out, but by the time we realized what the problem was it was too late to change the setup. So we had one slide show for people in the room using the built in computer and the same slides on the laptop for those on Zoom. 

The Zoom meeting format was used, rather than a webinar. There was only one instance of an open microphone disturbing the presentation, and the students policed that themselves with someone asked everyone to "mute you mic" in the chat forum. One of the staff monitored the audio quality and the chat questions, via another laptop. Students were invited to ask questions live by audio and that worked fine.

One problem was that because the students in the room were not watching the Zoom session, they could see the remote presenter's slides, but not the presenter. So in that way the remote students had a better experience than those in the room.

The Zoom session was left open after the presentations for further student questions, while other staff handled questions in the room. There were mostly of the "can I still enroll, get into a tutorial group, resister for a project" type.

This was my first hybrid presentation for some time and I had forgotten how stressful it is, but how rewarding it is to be in a room with students and colleagues. Added to the stress of talking to a very bright and demanding audience, is added the complication of making sure you remain in the field of view of the camera, and ensure the slides are working for two audiences. It worked okay, but I still provided students with a recorded video version in advance, in case something went wrong live.

Lighting for Video Conferences

6in. Tabletop Selfie Ring Light

 When using a virtual background with video conferencing, it is important to have even lighting, otherwise part of you may be chopped off, or the real background visible. Any office lamp will do, but there are ring lights available specially for this purpose. The ring lights have a circle of LED lights,and are designed to go around the camera lens.  I find it too distracting to be looking directly into the light, so instead have it at 45% pointing at the wall, behind my computer screen. This reflects a soft light onto the background.

Power-bank with light

Ring lights are available in different sizes with clamps, and stands. Some also have a clamp for a smart phone (and are called "selfie lights). The one I have has a desktop tripod and can be rotated and swiveled. It cost $8 from a local store and plugs into a USB power supply. For portable use, away from mains power, I also have a power-bank, with a built in flood light and USB sockets for ring lights ($19 from a local store). 

Telephoto Lens for Closeup in Zoom Meetings

2x telephoto lens & virtual background in Zoom. 
Tom Worthington, 24 July 2021 CC BY

Web cameras tend to have a wider field of view, than needed for one person attending a video conference. This makes the camera easy to set up, but shows more of the background and less of the speaker. My Logitech C615 webcam has a 74-degree field of view. So I purchased a 2x Telephoto clip on lens.

The clip-on lens is designed for use with a smartphone camera, but works well with the camera in a laptop or stand-alone web camera. The lens is screwed onto what looks like a clothes peg, which is clipped over the camera. It takes some effort to position, but is then held firmly.

198 Degree Fish-eye Lens, 
Tom Worthington,
24 July 2021, CC BY

With Polarizing Filter, 
Tom Worthington
24 July 2021, CC BY

I purchased a kit*, which came with fish-eye, wide, and macro lenses, as well as a polarizing filter. The fish-eye or wide-angle lenses might be of use for showing the general view of a room, but distort the image. The polarizing filter is useful for removing reflections from my glasses, however it can't be used in conjunction with the telephoto lens.

Without telephoto lens.
Tom Worthington,
24 July 2021 CC BY

With 2x Telephoto Lens. 
Tom Worthington
24 July 2021 CC BY

As well as narrowing the view, so less of the room is visible, the telephoto lens also makes the background slightly out of focus. This is useful for concentrating the viewer's attention on you in the foreground. Otherwise they might spend their time reading the titles of the books in your bookcase. ;-)

The narrower view also allows a smaller green screen to be used for a virtual background. In the example shown, I am using a sheet of lime green polyester acoustic pin-board, 1200 mm x 800 mm ($30.50 from a hardware store). 

Most of the clip on lenses sold for smart phone are wide angle. It took me some time to find a telephoto. One online store sent me a wide angle instead of a telephoto. So for the first time, in a long time, I went into a camera store. The kit I purchased is an Apexel 5 in 1 Clip on Lens Kit ($19.95 from Ted's Cameras, Canberra Center). Note that you will only need a 2x telephoto lens and there are higher quality units available separately at a higher price.

Folding Lilac Screen for Virtual Zoom Background

The second hand folding room divider

Lilac folding screen, in Zoom
with virtual background. 
Vertical fold lines visible. 
Photo by Tom Worthington,
 23 July 2021 CC BY

Lilac folding screen,
vertical fold lines visible. 
Photo by Tom Worthington,
 23 July 2021 CC BY

, I painted blue for virtual backgrounds, was too dark to work well with Zoom. So I went back to the paint shop and had a lighter shade made up. This was intended to be a bright blue, and the hex code for the color looks blue on screen (#0061FF). However, the paint looks more Lilac, but works well with Zoom.

QR Code for 
Bright Blue #0061FF 
from 
Taubmans Coloursmith

Folding Blue Screen for Under $20

Blue folding screen,
with vertical fold lines.
Photo by Tom Worthington,
 20 July 2021 CC BY

The second hand folding room divider , I painted green for virtual Zoom backgrounds, works well but what if I want to wear green? The most common alternative to green, as a chroma key background, is blue. So I painted the other side of the divider blue. This did not work as well with Zoom as the green side.

QR Code for blue, from the 
Taubmans Coloursmith application

There appears less standardization on the shade of blue used, compared to green. I chose Hex color #0047BB (close to PANTONE 2728 C), as one of the most common mentioned in the literature. I uploaded an image this color to the Taubmans Coloursmith application. This produced a barcode, which I took this to the local hardware store to have a sample paint pot made up (less than $10 for 250 ml).

Blue

Blue folding screen, in Zoom
with virtual background. 
Vertical fold lines visible. 
Photo by Tom Worthington,
 20 July 2021 CC BY

Zoom was not able to delineate the dark blue background as well as the lighter green. Also the joins in the screen showed more than with green. The paint looked darker, and more purple than blue, when painted on the screen. 

QR Code for 
Bright Blue #0061FF 
from 
Taubmans Coloursmith

The literature points out that a blue screen will need more light than a green screen. But it may be that a less dark shade of blue would work better in an office, where studio lighting is not available. The lightest possible shade of this would be #0061FF. Another option would be the "Hi C Blue" (#0174b3) which is one of the standard colors of the Taubmans range.

Green

QR Code for green, from the 
Taubmans Coloursmith application

I also used the Colorsmith application to make Chroma Key Green. This looks almost identical to the Dulux Zatar Leaf color I had made previously.

Folding Green Screen for Under $20

Green folding screen,
with two vertical fold lines.
Photo by Tom Worthington,
 17 July 2021 CC BY

The low cost photographic backdrop sheet I purchased, for making virtual Zoom backgrounds, works well but takes time to hang. I found a folding room divider screen at a charity store for $5. These type of screens are available online for under $100. I decided to paint it chroma key green. I tried the local hardware store, but they had never heard of chroma key.  The friendly staff at the I inquired via the Dulux website advised that the closest color in their consumer range was Zatar Leaf, or if I wanted the exact color it could be mixed at their trade store. So I went back to the hardware store and asked for a sample pot of Zatar Leaf (less than $10 for 250 ml).

Green folding screen,
with virtual background.
Fold lines are hidden by Zoom.
Photo by Tom Worthington,
 17 July 2021 CC BY

The screen is covered with canvas having a large photo mural on it. I painted over one side of the screen with a small roller. I also painted the sides of the screen. For the screen to stand it has to have the panels hinged in slightly. I placed the screen just behind my chair. As you can see in the photo, the joins in the screen are clearly visible as two vertical lines. I thought I would have to cover these with green tape. However, when Zoom's virtual background is switched on the lines disappear. 

This screen is only 1200 mm wide and has to be so close to fill the view, it is a bit cramped in front. I could use a camera with a narrower field of view, but a screen with four, rather than three 400 mm panels would be more practical.

I am considering painting the other side of the screen with chroma key blue. An alternative is to leave it with a decorative pattern, so I can put the screen in front of the desk when not in use so the room looks less like an office.

A $4 Green Screen for Zoom Background

Tom Worthington
in chroma key body suit,
without hood, so just face shows

For the last year and a half I have been giving workshops from home, via Zoom, for students in Australia, also presenting a series of seminars for educators in North America. The background in my lounge/office is a wall, with a couple of posters, must be getting very familiar to people. Zoom has the option to replace the background with a photo, or even your presentation slides, but this works best with a uniformly colored background. Zoom recommends a green background. 

Tom Worthington in
chroma key body in front of green screen

This techniques is called Chroma key, where a specific color in an image is replaced with another image. While any color works, there are two standard ones used in the video industry, a bright green and a bright blue. If you use the standard colors, you can use props which match and will disappear into the background. An extreme example is having a person disappear.

Tom Worthington
in chroma key body suit
with hood covering face

Chroma key color cloth is commonly available for sale online. Recently I found a green chromakey bodysuit at a secondhand store. This is used for special effects. Covering the entire body, including hands and face, with the matching background, the wearer disappears. This could be used by assistants who need to walk on set or to make objects appear to move on their own. Those running online invigilated exams need to keep in mind the suit could be used to hide someone helping the student.

Tom Worthington
using the green screen
in normal clothes

Apple colored
Top Pop Poplin cloth,
from Spotlight

Being impatient to try out a green screen, I went to a local haberdashery store and purchased some green cloth (2 m of Apple colored Top Pop Poplin, from Spotlight, at $2 per m). I then clipped this to my room screen.  With a width of just under 2m and a height of 1.16 m this was enough to fill the background for the camera. This cloth is a little darker than the usual chroma key green, but worked well.

Stanford University Computer Science Zoom Class a Quantum Leap Backwards

Stanford University's large scale Zoom class

I had to check twice to see Stanford University's large scale Zoom class was not a spoof. With this setup the lecturer stands at a lectern in an otherwise empty room. In front of them is a wall of video screens, showing the students, each in their Zoom window. It is not the first time that this idea of replicating the large lecture has been attempted, but is perhaps the worst one. Previous examples were using hybrid mode. This had a small number of students in the classroom, with video screens at the back to make it appear they were in the room.

CSU College of Business collaborative classroom.
Photo by CSU Photography

In 2019, Colorado State University’s College of Business installed 27 high-video screens on the back wall of a classroom. The room also had seating for 37 students, in a semicircle, to give an intimate environment. This is a much better design than that at Stanford. 

There have been video studios for teaching, for at least the last 50 years, with the advent of the Open University. The best of these look like TV studios. That format may be distracting for academics unused to it. However, for those of us who have put in the hours and done the training in how to produce educational video, this is just part of the job.

The Internet provides new and different ways to provide education. Some of these can be used to reproduce features from older education format, such as the lecture. However, we should try to incorporate the good features, not bad ones. 

Education should be designed to cater to the needs of the students, not to make up for inadequacies of the teaching staff. Academics who see themselves as orators to crowds need to be given help to retrain and also overcome the sense of loss of part of their identity. Taking a poor educational format (the large lecture) and making it even poorer online is not an acceptable alternative to good learning design delivered by trained qualified educators.

ps: I suggest this is a quantum leap backwards in education. But in the technical sense of the term quantum: the smallest possible change. ;-)

The Best way to Avoid Zoom Fatigue is Not Have a Meeting

Jeremy N. Bailenson has written a thought provoking commentary on the causes of fatigue from using video conferencing (2021). He suggested Zoom, and similar video conference systems, cause the user to be tired due to: Eye Gaze at a Close Distance, Cognitive Load, An All Day Mirror, and Reduced Mobility. 

As Professor Bailenson notes, "... being on video-conference all day seems particularly exhausting ...". He suggests this is an area for research by social scientists and technologists.

However, I suggest the primary cause of the exhaustion may simply be from spending so much time in video conferencing. In a typical day pre-COVID19, I might attend a couple of face to face meetings. In between the meetings there was at least some break walking from one meeting to another. When I occasionally have had to attend, or chair, all day meetings, I have found this exhausting. Because it is so easy to schedule and attend video meetings, I have found some days in 2020 I go from meeting to meeting without a break. Some conferences which transitioned to online last year acknowledged this and scheduled breaks.

Eye Gaze at a Close Distance

Professor Bailenson identifies Eye Gaze at a Close Distance as a problem, with a video conferencing like staring at a group of people. I haven't noticed this as a problem, perhaps because I frequently have the screen set to display only the speaker, in a small "thumbnail" window. I do this to save on computer CPU and networking resources, but perhaps it also has benefits for the user. 

There are other video conference systems which try to mimic a meeting more closely. Remo displays a floor plan with people represented by small icons around tables. When you join a table, you see the video from just the few people around the table. Some systems attempt to provide a perspective view, showing people near you larger than those further away.

Cognitive Load

Professor Bailenson suggests that having to consciously attend to one's visual communication creates extra workload. However, in a face to face meeting I am conscious of the need to be visible to others and appear to be paying attention. This has been a problem when I am taking notes on a computer, but those around me think I am not paying attention and are using the computer for an unrelated task.

An All Day Mirror

As Professor Bailenson notes, Zoom's default option is to display the speaker on screen. I find this reassuring, but he suggests it is stressful. Perhaps one reason it doesn't bother me is that most of the time I have the video camera turned off and a stock image (taken from the same perspective, wearing the same clothes, displayed. I do this to reduce bandwidth use and also enable me to take notes without distracting other participants.

Reduced Mobility

Professor Bailenson suggest video conferencing reduces mobility because the participants need to stay in view of the camera. This is not the case. Video conferencing is available on phones as well as laptops and so can be mobile. It may be that we need features in the video system to encourage people to use this feature, or explicitly encourage them to do so.

Avoid Zoom Fatigue: Don't Have a Meeting

It may be that I suffer less Zoom fatigue because I was a user of low bandwidth video conferencing before 2020. As such I treat the video as an adjunct to the audio, and the audio as an adjunct to the text chat, and the text chat as an adjunct to asynchronous communication. 

Those who are used to working primarily via face to face meetings, including those used to teaching this way, find video conferencing the closest alternative available. However, this is not necessarily the best way of working. My approach is to try to get the work done asynchronously, as that save the time and trouble of having a "meeting". 

For ten years I was able to run online courses for university students which had no video or audio. Students never saw or spoke to me face to face or online, but were still able to learn and gave good ratings for my teaching. In decades of helping to run the Australian Computer Society I avoided meetings wherever possible, making decisions out of session.

The best way to avoid Zoom fatigue is not through better software design, but by not having fewer meetings.

References

Bailenson, J. N. (2021). Nonverbal Overload: A Theoretical Argument for the Causes of Zoom Fatigue. Technology, Mind, and Behavior, 2(1). https://doi.org/10.1037/tmb0000030

Have students provide a photo to help instructors feel good online

There has been much written about the stresses caused for students having to study online this year due to COVID-19. There has been less on the effect on teaching staff. One of my students is researching how to make online learning better and came across some work indicating students were happier with video conferencing than those teaching them. It occurred to me that some of the techniques online teachers are trained in to make them appear more human to the students might also be used to make the students appear more present to their teacher.

One of the basic techniques is to have a profile photo. This appears in a video conference if the camera is off. I use a still image taken by my web camera showing me dressed typically for a video conference with the usual background. When not speaking in a video conference, I suspect than many people don't notice I switch from live video to the still image. 

Teachers express frustration about talking to a Zoom screen showing rows of black rectangles. It is tempting to tell students to turn on their cameras, but there are many reasons they may be unwilling or unable to. I use a wireless broadband connection which sometimes can't support video. Sometimes I am in a shared office with people who do not want to be on camera. So I understand why students do not want to turn a camera on. 

On a visit to Cambridge University, some years ago, I came across research which suggested people relate to a computer as if it was human, if it has a face. This did not need to be high quality video, a still image, or even a smile face would do :-) 

So I suggest that having students include profile photos on their video would help teachers feel they are talking to people. This could be implemented by asking students, or by having the Learning Management System provide the official student photos to the video conference system by default.

EduTECH 2020 On Now

Greetings from EduTECH 2020 online via Zoom from Australia. This comes hot on the heels of EduTech Asia last week from Singapore. Pasi Sahlberg, Deputy Director of Research at Gonski Institute For Education UNSW is presenting evidence that Australian school teachers (and students) spend too much time in formal classes. He argues that there is no correlation between time in class and results and Australian teachers don't have time in their long days for innovation. His institute is investigating how digital media distracts students. This may also be applicable, I suspect, to university students as well. The solution I suggest is in the hands of those who train school teachers and university lecturers: show them how to teach differently, and make use of educational technology, so it helps rather hinder learning.

Terrapinn have put a lot of work into replicating their face to face events online and it mostly works. The plenary events online are, in some ways better than being there live: you can see and hear the speaker better in a video conference than in a large hall. Asking questions is much the same (Terrapinn.com) where already using an online system for curating questions face to face. Round-tables also work well online, where there is a celebrity leading a discussion  around a table. I have taken part in these live and they work just as well online. 

Terrapinn have also tried to facilitate personal meetings online. Participants put in their details and can use the conference system to contact people attending they know, or would like to know. The parts of a conference which don't work as well online are informal contacts and the exhibition. Part of the joy of a conference is running into people you know and being introduced to their colleagues. I am not sure how to reproduce this online. The other joy is wandering the exhibition talking to vendors and having incidental conversations with people who also stopped at the stands. An example is when I found Martin Dougiamas, founder and CEO of Moodle Pty Ltd, at EduTech Asia 2018 in Singapore.

One problem I have noticed with how Terapin have set up the event is that each presentation is in a separate Zoom conference. Unlike a face to face event, there is not the option to simply stay in the room for what is next. There is the option for each participants to build an individual agenda (I have loaded mine into my electronic diary). However, often at a conference I ask those around me what they are going to next, ignoring everything I have circled on the agenda.

Tuning Zoom Videoconferencing for a Slow computer and Low Speed Broadband

Greetings from the 2020 UQ Work Integrated Learning Symposium, currently on Zoom from Queensland University. This is free and on for four hours, so there may be time for you to join. The students are running the event, which shows commendable dogfooding by UQ.

To improve the performance of Zoom on my slow laptop, and low speed wireless broadband connection, I am trying a router with UDP shaping. 

Previously I noticed that with Zoom in full screen mode the sounds would break up and image freeze. If I reduced the window size it worked better, but this was fiddly. Also when a presenter shares their screen, Zoom tends to force the display back to full screen, after which I have to shrink it again.

An approach I tried in the past was to slow my Internet connection, which Zoom responded to by using lower resolution video, making everything more stable. However, this also slowed down all my other network use. There are software utilities which will slow just one application, but I found these did not work with Zoom.

The Internet uses two sorts of data transmission: TCP and UDP. Most applications, such as email and web browsing use TCP, as this provides a reliable connection. Video conferencing programs typically use UDP for the audio and video, as this has less overheads. The utilities I tried to slow an Internet connection only act on TCP, not UDP, so did not slow Zoom.

Not being able to find a software solution I turned to hardware. Many routers allow for slowing, or "shaping" of the speed of the connection. A few allow this to be targeted at TCP or UDP specifically. I tried a TP-Link TL-MR3020 V3 router (around $50 AU), and switched on the UDP shaping. So far it is working well.

Currently I have the data rates for UDP set to: 800 kbps transmitting and 512 kbps receiving. I want to provide a good quality standard definition image of myself when speaking, but a lower quality for the video I receive, so have sent the sending rate higher than receiving.

Zoom is currently providing an image of the speaker at 320 x 180 pixels, 12 frames per second and screen-sharing at 1440 x 900 pixels, 1 frame per second. The screen share looks very clear and readable, with a clear thumbnail of the speaker next to it. If a video is played in the screen sharing it looks jerky, but fortunately most presenters don't play videos.

A bigger test will come this evening, when I am speaking on "The Virtual University" (6pm, all welcome).

ps: One small glitch: after a short break when my computer went to standby mode the router was no longer connected: I had to reboot it.

pps: The video from some speakers was not appearing in Zoom gallery mode. So I increased the down speed from 512 kbps to 1024 kbps. The increased speed also allowed for screen sharing at 1920 x 1080 pixels at 8 frames per second, which is enough to follow a mouse around the screen and simple animation. In speaker's view the video is now at 640 x 360 pixels 26 frames per second. However, this is using too much of the limited CPU in my computer, so I will try setting up and down speeds to 800 kbps.

ppps: Had problems with the  TP-Link TL-MR3020 router, so changed it for the desktop version, a TL-MR3420, which is working well.

Ask Zoom for a Low Bandwidth Option

Back in March I suggested to Zoom, they add a low bandwidth option which the participant can switch on (request #3204325, priority "high", 26 March). The documentation says screen sharing with video thumbnail is possible at 50-150kbps, but I could not get that to work, even when I shaped my network connection to that speed. As well as allowing to user to activate this manually, I asked Zoom to adjust their system so it came on automatically, sooner. Since then I have experimented with how to reduce the bandwidth Zoom uses, so it works better on slow links, particularity wireless ones. But there are many people who still have difficulties. On 4 August, Zoom replied to say my suggestion had been added to their feature request list. But it took Zoom four months to reply, so they don't seem to be in a hurry to implement this. If you think it is a good idea, please tell Zoom.