LIGHTING OPTIONS FOR SHOWCASES

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The following are key considerations for design and conservation reasons

  • Control of light levels
  • Filtration of ultra violet radiation
  • Minimal build up of heat within display
  • Filtration of infra red light
  • Ease of maintenance
  • Maintenance external to displays
  • Directional control
  • Flexible set up for changing displays
  • Colour rendering of lamps.
SPECIALIST LIGHTING FOR MUSEUM SHOWCASES.

Fibre Optic Lighting
Fibre optics meet all the key requirements for the safe lighting of museum objects.
Whilst the initial cost may seem high, fibre optics are cheaper to install and have lower maintenance costs than a low voltage system.

System Components
F.O. light source - the light source houses the lamp, dimmer, filters and transformer and requires mains power.
As the light source generates heat, it should be mounted away from the display area in an accessible position for maintenance.
The unit should have a built in cooling fan otherwise lamp life may be reduced due to overheating. Two types of source are available, tungsten halogen or metal halide.
The tungsten halogen source is more commonly used due to the colour rendering, lower cost and smaller unit size.
F.O. harness - the common end of the harness fits into the light source and is the junction for a number of tails through which the light passes to the end fittings. Tails are available in a number of sizes and careful planning is required to determine tail length and their route as they cannot make tight bends. Light transmission will be reduced considerably with tail lengths of over 5 metres.
F.O. end fittings - a range of end fittings can be used to provide the desired effect. Fittings should have an adjustable beam angle and also a locking screw so that they do not
deflect with the weight of the tail.
Fittings should be manufactured from inert materials and should be sealed to prevent dust and pollutants entering the case.

Types of Fitting
F.O. trumpet down lighter - mounted into any part of the case or internal mounts this fitting can be directed within the case to highlight objects. The fitting can also be mounted into a steel bracket for use over a diffuser.
F.O. flush down lighter - a discrete adjustable fitting which can be mounted into any part of the case or internal mounts.
F.O. track fitting - similar in shape to the trumpet head this fitting is track mounted to make it more flexible within changing displays. Shown here shrouded by label rail.
F.O. swan neck - particularly for use in Prism cases with books, textiles and maps.
F.O. gantry - a horizontal tube with concealed fibre optic heads used to provide an even wash of light

Fluorescent Lighting
Fluorescent lighting is ideal where general lighting is required within a case and it can be supplemented with spot lighting if desired

System Components
Control gear - electronic control gear should be used in preference to traditional control gear as it uses less energy, gives longer lamp life and freedom from flicker. It is also possible to specify a dimming facility if required.
Lamps - high frequency fluorescent lamps for the electronic control gear are available in a variety of colour temperatures to give a true colour rendering of objects, paintings and textiles. Lengths from 450mm to1500mm can be easily installed within the top lighting section of cases.
Fittings - standard fittings can be bought which incorporate the control gear and lamp within one unit for ease of installation, or, the control gear can be mounted remotely to the lamps to reduce heat build up within the case.

Low Voltage Lighting
Low voltage lighting is very versatile for use in showcases and there is a wide range of fittings and lamp types available.

System Components

L.V. Light Fittings
L.V. eyeball down lighter - mounted into a soffit this fitting can be adjusted within the case to highlight objects.
L.V. skeleton bracket - this fitting fits on a diffuser and can be positioned and angled to suit. Once positioned the fitting locks in place to prevent disturbance of the lighting set up during maintenance.
L.V. spotlight - a fully adjustable spotlight can be used within cases where the objects are not heat sensitive.
Low voltage lights must not be used directly over plastic which may melt or burn.
Lamp - a range of wattages and beam angles are available to suit most display situations. These should be glass fronted with minimal spillage through the back of the reflector. Care should be taken to replace lamps with the same wattage and beam angle as the original.
Transformer - electronic transformers with dimmers are ideal for use with low voltage showcase lighting as they are compact in size and can be adjusted to give the correct lux levels on sensitive objects.

Diffusers
The diffuser provides a barrier between the display area and the top lighting section and is formed from several layers.
A range of cellular, glass, solid, louvre and filtering materials can be incorporated within the diffuser layer to meet performance requirements.
A cellular material provides structural support, diffuses light and conceals fittings.
Stippled laminated glass provides a dust seal, diffuses light, absorbs heat and laminated interlayer provides a UV filter.
Laminated glass provides a dust seal, security barrier and absorbs both heat and 97% of UV radiation between 320
& 380 nanometres.
Whilst we are able to provide and install a wide range of lighting systems we recommend that the advice of a specialist lighting designer be sought.