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ADVICE FOR POTENTIAL USERS
Satisfaction with current set-up
Users were asked whether they were happy with their overall set-up and whether they would recommend what they have to other potential users. They were also asked if there were any extra facilities that they would like to see incorporated and whether they were indeed considering the purchase of any related equipment.
It seems that most respondents are basically happy with their current facilities, with well over 75% prepared to recommend what they were using. Specific factors which would influence these recommendations are listed below.
N.B. The letters in brackets refer to the example configurations given in Appendix 3.
- flexibility (e.g. because the combination of video and digital signal transmission allows the juggling of many parameters to arrive at any kind of video image possible) (d)
- suitability for distance education (i)
- cost-effectiveness (j)
- high potential (j)
- ease of use (k)
- high studio quality (n)
One respondent felt the equipment they were using was not yet stable enough to be recommended to others, but that videoconferencing could be a very useful communications tool once the bugs are ironed out.
For others there was not a simple answer to this question. While they would endorse some products, they were finding others to be redundant or too costly. Some felt that they were not in a position to make recommendations because their equipment has been largely determined (and funded) by outside bodies.
The point was made that recommendations would depend on the potential users’ situation and the uses they anticipated for videoconferencing. For example, a site with a low bandwidth Internet connection and no money to lease private lines will be limited in the technology they can use effectively.
However, a variety of problems and deficiencies, some of which were of a technical nature while others were concerned with the usability of the system.
Problems identified
Technical problems
- Sound quality is not always provided to acceptable levels (noise and rumble are unacceptable). Some tools (such as vat and maven) are particularly subject to sound break-up.
- CU-SeeMe needs improvement in the areas of audio support and colour. It would also benefit from some recording/playback tools, akin to the media-on- demand software for the MBONE.
- MBONE audio/video synchronisation needs improvement.
- Incompatibility between different components. For example, PictureTel does not interface with BT bridge equipment.
- PictureTel demonstrates poor resolution, especially for document sharing and computer screen sharing.
- Jerky video motion is sometimes annoying.
- Projection of vu-graphs by way of a video camera is not acceptable.
Usability issues
- Significant propagation delay (in the use of PictureTel) makes verbal interjection awkward.
- The non-colinearity of monitor and camera will mean that eye-to-eye contact is not complete.
- Inadequate preparation by speakers is still a problem.
- CU-SeeMe makes it easy for novice users to break the Internet for everyone. User education is the only effective countermeasure to date.
- Users would like to see easier control systems to handle different cameras and resources. The digital systems are not as flexible as the analogue systems and we would like to see development to give this level of flexibility of interaction. The digital system are
more formal as there are time delays, which tend to kill spontaneity.
Extra facilities required
- Computer application sharing.
- Desk-top office systems, either standalone or PC-based (to supplement PictureTel which is installed in a dedicated videoconferencing room).
- Document viewer.
- Proper dedicated videoconferencing room.
- A small occasional studio (to supplement the existing videoconferencing studio).
- Split screen.
- ISDN compatibility.
- Better conference control tools (floor control, etc.).
- Remote control of camera pan and zoom. (N.B. This is incorporated into the ES f- 2-f software — which is very clever — but it is rather limited.)
- Video boards for some HP PCs, and some cameras to suit.
- Better cameras.
- Faster link to Internet (currently 57.6K).
- Faster networks with guaranteed bandwidth.
- MCU and PBX.
- Large SPARCstation with FDDI interface to replace current MBONE router.
- Large digital servers for multimedia resources.
- More compact and cheaper workstations.
- Cheaper codecs.
- The possibility to run remotely (Windows_ or Mac) programs in Vis-A-Vis- program (i.e. the ability to use Vis-a-Vis to connect from distant locations to the server.)
- 3D.
Facilities considered to be superfluous
The majority of respondents found none of their facilities to be superfluous, making regular use of most of the features available to them. One user found their video mixer to be superfluous and another found that they were not making much use of the shared drawing application. The split screen facility was falling into disuse at a third site because of the need to keep moving the cameras around in order to set it up.
The point was made that document sharing is often better done by fax and computer screen sharing is better done using computer network technology.
Two-way text conversation can often seem unnecessary, considering you are already in verbal contact.
Specific pieces of advice
- Practise! Even institutions which have been using the technology for several years admit that they are still learning and still do not get it right all of the time.
- Think very carefully about your requirements and your intended uses of the technology.
- Try to see systems in operation to decide which matches your need.
- Be clear about the distinction between desk-top and full screen techniques and the difference between conferencing and distance teaching.
- Be aware of the kind of image you will be dealing with on a day-to-day basis (because although the Information Superhighway will offer substantially increased bandwidth, there is still going to be a lot of traffic and this will affect transmissions).
- Consider whether you really need a moving picture. In many cases a digital camera or scanner connected to a computer will suffice. Still pictures give quite a lot information and shaking heads are sometimes annoying (especially in an ISDN connection).
- Decide in advance on the protocols of use which will allow the equipment to be integrated into your work environment. For example:-
- Is it going to be on all the time?
- Who will the cameras be pointed at?
- What sort of control will they require over the images they transmit?
- Get the best facilities you can afford from the beginning, making sure that every link in the chain has adequate performance. A good sound system is especially important.
- Proprietary set-ups are more robust than customised ones, unless you like “tinkering”!
- If multicasting a lecture make sure that you set your gear up at least a day in advance, test all the connections, get a stable platform for the camera (which should be a decent video camera with zoom lens) and most importantly get decent audio set up (lots of microphones near the speakers/audience and a mixer unit between them and the workstation).
- Wait. In the case of ISDN-based systems, wait until the standards and compatibility issues have been sorted out and the technology (mainly software) is more stable.
- Use Macintoshes; in the long run they save money and effort.
- Have face-to-face meetings as well, especially at the start.
- Voice switching takes a little getting used to but is excellent.
- Check out all of the video server software very carefully before buying. Most of the video conferencing software is badly done.
- Watch the software cost and the video board being used; it can get very expensive.
- Make sure the software runs on several network platforms. TCP/IP over Ethernet, T1, and FDDI infrastructures should be a norm. If it only uses ISDN don’t use it. Tests show that ISDN is late and too slow to be of any help in a high speed image network.
- Look for cross platform software — workstation to PC connect is the best.
- Give careful consideration to the quality of the display. Many monitors and data projectors have a poor quality picture. No matter what the tests say, the only display you can watch for hours without getting sore eyes is non-radiating, non-pulsar Activ-Matrix or Electro-luminens displays. Unfortunately these displays are too expensive and too small at the moment.
- Get in touch with people who have been using the facilities (see Appendix 4 for possible contacts).
- PC-based videoconferencing is a compact solution; but when there are, say, eight different cards inside the PC, real problems start to occur. Compact often means risky.
- Bear in mind that videoconferencing over a wide area (e.g. the Internet) is experimental, and you may be treading on an awful lot of people’s toes by broadcasting high bandwidth video on public networks.
- Try it to learn something about new options for yourself and your organisation. But do some reading about what others have done and see how their models might apply to you and what you want to do. Do learn from others and don’t assume that your plans or needs are unique!
- The best is yet to come!
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Graphics Multimedia
Virtual Environments Visualisation
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