Preparing and optimising your video for teaching

This post introduces the casual video maker to the subject of optimising video for teaching at UTS. Recommendations are framed within the scope of making video available to students in UTSonline, across a range of devices and in the most accessible way.

On this page:

Making and using video for teaching from a practical and pedagogically sound position should be your focus. Your faculty liaison in IML and Learning Technologist can advise you further. If you want to pursue in detail the mechanics of video production the links at the end of this post can help. A number of UTS examples can also be found on the Learning.Futures webpage.

An effective video for learning is not necessarily a technically great video. Don’t stress over the technical details, but learn as you go, everyone has to start somewhere. A hastily made video with great content, available to the students when they need it the most, is better than a video delivered too late to be useful. Whatever method you employ to make and share video with students, what matters is relevance, convenience and accessibility.

The good news is that you won’t really need to think too much about your video formats or compression when you upload to YouTube for playback through UTSonline. YouTube takes care of the technical details that relate to streaming your video in the best way to a variety of devices. As a result, you get to focus on the quality of your content.

Cartoon: What matters is relevance, convenience and accessibility

‘Watchability’ and Accessibility

‘Less is more’ when it comes to videos used in teaching. A basic welcome video should be short (up to 60sec), while subject and discipline video tours can be longer (less than 3mins). For detailed subject specific video tutorials, stick to one key topic per video (less than 5min) and group related topics in a playlist.

A topic-by-topic approach that mirrors the subject teaching timeline helps students easily locate material, especially for revision. A modular approach also affords you more flexibility in producing, re-using and managing videos within or across subjects. Should you ever need to reorder, update or remove a video, doing so will be much easier when your content is organised in smaller discrete units.

Accessibility

Once you have your video, you might need to provide an accessible alternative to any important information by attaching a transcript in UTSOnline. You can easily create subtitles and closed captions while a custom thumbnail can visually list the video content (the still image you see before pressing the play button). At minimum, always include a text description of important details alongside any video you embed.

If your video is long and covers a wide variety of material, list this information in the text description, in order of appearance. Try to include section/topic titles in your videos to visually aid skipping to relevant content. Start your video with a spoken and visual summary so students know what is covered up front (and the visual will automatically become the thumbnail image). With YouTube you can start a video at a particular point to help students find specific content. There are online services to help you restrict playback to a portion of a video to focus attention on the parts that matter like Vibby.

Think about when, where and how students are likely to watch your video. It might be on a mobile device while they’re commuting, or on a slow internet connection where duration and download size matter.Cartoon: students will watch a video if it is linked to assessment

A video can be as long as it needs to be while it continues to remain interesting and relevant to your target audience – the students. What you can get away with in terms of duration depends on how compelling you are in terms of content, pace and delivery. Being entertaining helps, if that comes naturally to you. The biggest factor which determines whether students are prepared to watch a video (and for how long) depends on the value the students place on your video and this is directly related to assessment. If the video is aligned with assessment, you are guaranteed an audience.

Consider asking your target audience—the students—to give you constructive feedback on your videos. Allow the students to have a hand in shaping video content for the next cohort. Ask students what topics they findmost difficult and let that be the driver for creating a video. You’ll get a feel for what works and what is valued.

Quality – well that depends…

The required ‘quality’ for a video in a teaching context is not the same as video created for exhibition or television – it depends on a number of factors, not just the technical issues. How much time do you have? What equipment is available? Is the video a quick one-off or will it be reused over a few years? A design or media subject can justify higher production values to reflect the kind of work expected from students – but only up to a point.

Remember that your video is only going to be seen by a limited number of students, for one teaching session in a specific subject and usually behind the restricted log-in area for UTSOnline. How much effort is your video worth in this context given that your focus will usually be more on the content not the style?

Despite these considerations, always upload the best audio-visual quality you can and let YouTube or Vimeo take care of all the optimisation and streaming. These services are designed to stream video efficiently and maximise accessibility. If you want to get technical and fine-tune compression, explore the detailed YouTube and Vimeo links towards the end of this page.

How you record your video and sound affects the final quality. Visual ‘noise’ reduces compression efficiency (files are larger) and consequently introduces more noticeable artefacts (distortion through detail loss). There are techniques to improve the quality of your video and help reduce both camera and microphone noise.

Tips to improve the quality of live-action video

  • Use a tripod, eliminate camera shake.
  • If you don’t have a tripod or it is inconvenient, then use anything at hand to stabilise the camera. Hold the camera close to your body bracing your elbows on your chest, lean against a wall or post. Rest the smartphone on a ledge, shelf, bag… anything helps.
  • If holding a smartphone, use both hands to grip your device. Relax your upper body, muscle tension will cause shakiness as you become fatigued. Move slowly, turning the camera with your whole body rather than your wrists.
  • Don’t use digital zoom on any camera, move the camera closer to the subject.
  • Minimise onscreen movement and non-essential detail. Interframe and intraframe differences are what challenge compression (increase file size).
  • Frame your subject closely, minimising background detail and movement or set up an appropriate background for your video.
  • Use depth-of-field to make the background out of focus (blurry images compress better).
  • Plenty of light is essential for a clean image. Inadequate light forces the average camera to electronically compensate—called video gain—and this leads to a grainy picture.
  • Soft, diffuse natural lighting is easier to manage than harsh direct light. This helps to reduce contrast range, flatten details and is more pleasing on faces.
  • Use a camera app on your device that enables manual control (switching off automatic video and audio gain).
  • Use an appropriate type of microphone and the best you can find. The UTS Audio Visual Service can help. With the right techniques and cheap microphones your smartphone or tablet can record great audio (talk to your faculty Learning Technologist for more information).
  • Record in a quiet location away from air-conditioning, computer fans and extraneous noise if possible. Remember to switch mobile devices into silent or ‘Airplane’ mode. Switch off anything on computers that makes a noise (email and social media alerts).
  • Room acoustics can dramatically change the quality of your sound recording, but you can easily improve your sound for free. The size, shape, materials and contents of a room can be manipulated to minimise reverberation and improve ambience. In spacious rooms with hard reflective surfaces the use of soft furnishings, carpet, curtains—even piles of books—can improve the way your voice sounds.
  • Get the microphone close to the sound source, especially in noisy locations. Any microphone benefits by being closer to the speaker, as long as you are aware of the proximity effect. A strong sound signal reduces the need to electronically compensate through audio gain which increases noise levels.
  • Recording or converting your audio to mono can halve the file space required for sound. Stereo sound is unnecessary for common tasks.

Unlike live-action video, Screencasts typically have only small visual changes, long static pauses and large areas of clean flat colour – all of which contribute to a small file sizes.

Shelf life

Content and structure influence how well a video can be repurposed. There are techniques to help minimise re-recording and re-editing material each semester:

  • Where possible break subject matter down into smaller discrete segments as described earlier.
  • Try to use the same equipment, process, location and lighting, wear the same clothes, use the same backdrop – anything you can manage to minimise continuity errors.
  • Once you have your favourite recording, editing and export settings stick with them. This permits mixing and matching material without jarring audio/visual conflicts.
  • Avoid mentioning in a video transient details like dates, events, locations, staff names, specific files and documents titles – these change. Use generic labels and direct students to content areas in UTSonline where specific details can be found (readings, announcements etc).

YouTube

YouTube is the recommended way to embed video in UTSOnline, This means the video is hosted on (stored) and streamed from YouTube, but is displayed in UTSOnline. The maximum file size for a video if hosted on YouTube is 128Gb (about 36 hours of full high definition video!).

By default YouTube restricts the duration of uploaded videos. You need to remove this limitation when you first create your YouTube channel so you can upload videos longer than 15 minutes. Doing this verification process also gives you the ability to add you own watermark and custom thumbnail.

If you have a very good reason to upload video directly into UTSOnline and can’t embed a link, you will be limited to a meagre 200Mb file size (around 8mins of medium quality high definition video). UTSonline is not designed to serve video in the ways dedicated services like YouTube can. UTSonline cannot stream video in an accessible way to multiple devices and students accessing videos may experience problems watching the videos on various devices or platforms unless you pay careful attention to the technicalities of video file size, format and compression. Follow the recommendations outlined in the links to YouTube and Vimeo below for the best result. This online tool can help you calculate video file size with respect to dimensions, duration and data rate to help you stay within the limits of UTSOnline.

Vimeo

Seek help for Vimeo issues in the Frequently Asked Questions. Vimeo looks at the recommended settings for video export and streaming in more technical detail in the Vimeo Help Center. The standard recommendations are basically the same as for YouTube (.mp4 video container format using the H.264 compression codec).

 

Self-help resources

This teaching blog you are reading now covers accessible video creation techniques using readily available tools and resources. Topics covered include making the most of your recording device, basic equipment and simple techniques. There will be new and revised posts, so be sure to check in now and then or subscribe to the feed.

The tag cloud, search box and categories can help you find specific content including:

Lynda.com provides online training across a range of video topics that can help improve your video production skills and to output optimal results. You can access this resource for free through UTS library website using your UTS email login credentials.

Faculty-based learning technologists maintain this blog and are available for consultation and advice. The best way to request help is via ServiceConnect.