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3.Local application of standards
Defining and Implementing Standards for Lecture Room Services
3 Local application of physical and technical standards
3.1 A room survey is currently being undertaken by BMS to collect data on relevant aspects of each room to enable an examination of the local application of the standards described in Section 2. This is proving to be a major task and work is still in progress. However, the data collected so far, while not exhaustive, at least supply some useful indications of the sorts of issues being faced. The Uxbridge Lecture Centre provided the main focus of this activity, particularly as many rooms are replicated, and examples exist of all three categories described in 2.3.12. Table 2 shows examples of some of the Lecture Centre rooms. However, certain other rooms at Uxbridge and other campuses are also cited to exemplify certain points.
3.2 Proportions, fixtures and services
3.2.1 Most screens are of the matt surface type, and are mostly wall-mounted. Lecture rooms in Categories 1 and 2 generally have fixed or electric roller screens and Category 3 rooms have manual roller screens.
3.2.2 Typical viewing angles were found to be excessive in comparison to the 45o standard. For example, 50 seat Category 1 rooms offer viewing angles in the region of 60o. While the seating is unfixed, the number of seats and tables generally provided in these rooms make it difficult to adopt more favourable viewing positions. In fixed-seating rooms, typical viewing angles are in the region of 53%. One explanation for this is that in a number of cases the rooms have in recent years had additional seating installed in front of the existing rows to maximise seating capacity. As well as being detrimental to optimum viewing conditions, this resulted in difficulties with positioning projection equipment. Accepting that alternative lenses may rectify the problem in certain cases, the cost implications of this had apparently not been allowed for within the seating extension project. Most of the 70-80 seat tiered lecture rooms have additional angled screens (1.5 m x 1.5 m) which assist with overcoming this difficulty and offer multiple display modes.
3.2.3 In terms of physical proportions, Table 2 also illustrates a number of points, both positive and negative:
(i) Typical floor to screen heights are about 30 cm lower than the standard 1.2 metres.
(ii) Typical screen sizes measured in relation distance V were found to compare favourably to adopted standards.
(iii) The distances between the screen and the front row of the are often significantly shorter than the adopted standard.
(iv) The typical distance from the top of the screen to the ceiling is 30 cm. Consideration of this together with the typical bottom of screen height suggests that ceiling heights in the Lecture Centre offer extremely limited margin for error.
The AV survey conducted by BMS in 1997 indicated a significant amount of dissatisfaction with the lighting control facilities. This was both in relation to control of electric lighting and daylight exclusion and was a general rather than room specific problem. While not within BMS's remit, it is nevertheless important for the Service to be proactive in improving these facilities as it is currently unable to offer optimum projection quality, no matter how good or up to date the equipment.
3.2.5 Room acoustics have yet to be systematically examined, though there were a small number of comments in the 1997 AV Survey indicating improvements were required. There are however some anecdotal observations worth recording:
(i) Most Category 3 rooms tend to have polished floors rather than carpets. While carpets would reduce noise caused by moving chairs, footsteps, etc., there is a resistance to fitting them in such rooms because of cleaning and replacement costs.
(ii) While some purpose built rooms appear to have reasonably good isolation, external noise from air and road traffic is a significant problem for one campus in particular, especially in the Summer when windows need to be open for ventilation.
(iii) There are a number of older buildings that have been converted to provide additional lecture rooms. For example, about 10 years ago a chapel was converted into a 160 seat Category 2 lecture room. The ceiling was parabolic in section and produced a delay of several seconds from a single clap test. As students could not hear the lecturers, pressure was imposed to install a PA system. This, if anything, exacerbated the problem. Ultimately a suspended ceiling was installed and this greatly improved both the acoustics and the efficiency of the PA system.
3.3.1 Most lecture rooms have a resident overhead projector (OHP) and efforts have been made to limit the range of models. A replacement project has recently been completed in the Lecture Centre to offer high quality 400 watt and 250 watt projectors with dual lamp facility and built-in mains socket for using additional equipment such as LCD panels. A limited number have roll attachments fitted where there is a known ongoing expectation for this provision. The new projectors offer colour fringe correction and also have relatively quite cooling fans. The typical focal length is 315 mm giving projection distances ranging between 1.6 m and 2.9 m for the rooms in Table 2. In these specific cases, when aiming to achieve the minimum screen size appropriate to a room's distance V, the space in front of the seating has been just sufficient to allow appropriate positioning of the OHP when using centrally mounted screens.
3.3.2 There is a good stock of 35mm slide projectors, either permanently installed or available for loan or delivery from the local BMS Centre. Both cable and infra-red remote control facilities are available. A number of rooms, particularly the Lecture Centre theatres, have front-to-back cable links for remote control. Loan stock projectors have zoom lenses so that they can be readily used in a wide range of situations. Multiple projection requirement is rare.
3.3.3 There are a range of television screens in use. In recent years it has been practice to purchase Supercreens on trolley bases incorporating a video cabinet. These offer good quality images up to 46" (117 cm) diagonal. In addition to standard PAL VHS replay these are sometimes used for NTSC video display and for data display via a VGA to video converter. A practical consideration is that they just about fit though doorways so that in certain buildings the same unit can service a number of lecture rooms. Using Table 1 it is been possible to determine that these systems are suitable for video display in rooms where distance V is 11.5 metres or less and for data display in rooms where distance V is 7 metres or less. Applied to the Lecture Centre, this is effectively all Category 3 rooms and extends to Category 2 rooms for video display. These trolley Supercreen systems have a floor to bottom screen height of 117 cm, which is slightly lower than the standard height. Typical screen sizes for conventional TV screens range from 14" (34 cm) for portable VHS presenters to 28" (66 cm) monitors on trolleys. Effectively this means that the former is only really suitable for seminars and the latter for video display in rooms where V is 7 metres or less. Existing TV installations will therefore be reviewed to ensure suitability. Most stands for these screens conform to the 1.2 m height standard.
3.3.4 There are a relatively small number of LCD projectors and LCD panels in use. However, the projectors are mostly current models offering uncompressed SVGA and reasonable brightness levels (up to 700 lumens). Demand is such that current expenditure priority is to increase stock levels of LCD projectors. LCD panels have largely been consigned to a back-up role. Two LCD projectors have been installed ceiling-mounted in Category 3 rooms, largely due to the front row seating problem described in 3.2.2. These are operated from the front rather than the projection booth and cabinets have been installed containing the interface unit, VHS playback, sound amplification and microphone equipment.
3.3.5 Some rooms have CRT projection installations, all over 5 years old and some having limited scanning frequencies. It is notable that with one exception these installations have been made as part of a building project, either a new extension or an adaptation. Most are in the larger of the University's lecture rooms and the level of associated installation work means that these are normally the best equipped rooms. Effectively, only one is capable of SVGA projection and this is located in a specialist PC laboratory. Inevitably, these will require replacement during the next 5 years or so, probably with suitable LCD projectors. In view of the level of associated installation, it is likely that the replacements will also be ceiling- mounted. It is perhaps useful to note that the projector in the University's Howell Theatre (400 seats), is mounted on an elevator assembly as it would otherwise interfere with the beam projected from the booth at the back of the room.
3.3.6 VHS video playback machines are widely available for use in lecture rooms, some offering extended facilities such as NTSC playback, Long Play or S-VHS. There are no immediate plans to replace this provision, although equipment stock is being extended to provide more specialised applications such laserdisc playback. Central copying services are provided enabling copying to and from other video formats. There is a good stock of portable VHS and S-VHS camcorder equipment that is occasionally used for recording lectures, in addition to central television and sound recording facilities. BMS also operates an extensive off-air recording service for the University.
3.3.7 The CRT and LCD projection installations have normally required a good level of audio equipment installation and such rooms normally offer a good quality amplifier and speaker installation for video playback and microphone input. The microphones used have normally been tie-clip radio types and Brunel is currently operating at full capacity on some campuses in terms of radio operating frequencies. While the power rating of the amplifiers is perceived to be fit-for- purpose, evidently most installations would benefit from additional speakers. Only the Howell Theatre has a PA installation that includes a sufficient number of ceiling mounted speakers to provide an even distribution. For rooms having no systems, portable combination amplifiers are available for loan, some incorporating audiocassette playback, for use in rooms with no installed reproduction or PA facilities. The Howell Theatre also has an induction loop installation. Induction loop systems have also been installed retrospectively in some lecture rooms at Twickenham and Osterley campuses as part of a special project. Similar installations are being planned for the main theatres at Uxbridge but here there are significant problems arising from their close proximity and consequent need to eliminate possibility of overlapping induction fields. Some portable neck-loop systems are available for loan to students to use in other lecture rooms.
3.3.8 Computing facilities in lecture rooms have been given relatively low priority in comparison to providing a good level of student access to PCs and systems infrastructure for the academic departments. Details of Brunel's computer network can be found at URL http://www.brunel.ac.uk/depts/cc/network . Few lecture rooms currently have Class 5 UTP network points, though it is understood that the Computing Service is planning to extend network provision in this area. BMS has therefore had to adopt a largely non-networked approach to using PCs in lecture rooms. For the Lecture Centre a single PC on a trolley has normally been provided but more recently notebook PCs have been purchased offering portability and higher level of multimedia capability. There is also a case being examined to offer portable Macs in addition facility. BMS is tackling the issue of supporting multimedia notebooks in the context of skills development (see 4.5.5).
3.3.9 While film projection has largely been superseded by video, there are some rooms offering 16 mm projection facilities and these are likely to continue to be required for specialised subjects such as film studies.
3.3.10 There is at least one lecture room with an internal telephone installed so that a lecturer can call for help. This has worked most effectively on a number of occasions but there are no immediate plans to extend this to other rooms.
3.3.11 There is no central lecture room videoconferencing service as such and most activity at Brunel has been initiated within academic departments. BMS is currently examining the feasibility of offering a service as an extension to its television recording service.
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