Lighting.
Lighting. A conflict.
Light is a prime example of the conflict between object display and preventive conservation. Without light, we cannot see, but light is problematic for object conservation because of specific wavelengths such as UV and IR radiation and the sheer amount of light to which objects are exposed.
Light is not only important for the legibility of objects, it also creates atmosphere and mood, which are essential to the experience of an exhibition.
Good lighting
A good lighting solution should combine pleasant atmospheric lighting with good legibility of the object, considering object-specific conservation requirements. Good lighting is characterised by an appropriate lighting level, harmonious brightness distribution, avoidance of direct glare and disturbing
reflections, correct light direction, good modelling of objects, a conscious choice of light colour as well as light sources with good colour rendering and flicker-free operation. Glasbau Hahn supports lighting designers and their clients in this planning process.
Conservation principles.
In general, the amount of light allowed per object in lux/h is one of the most important design principles for a display case lighting designer. The filtering of UV and IR radiation emitted by light sources has become redundant with the almost exclusive use of LED lighting. The only problem is daylight. Glasbau Hahn therefore only uses display case glass with over 99.5% UV-A protection. The heating of objects with high-energy light sources can lead to partial drying out and damage due to partial shrinkage of heated object areas. Although this is less of a problem with LED lighting, the heat generated by the electrical resistance of the luminaires can still have a negative effect on the microclimate, particularly the relative humidity. It is therefore still important to thermally isolate technical areas from display areas. Although LED lighting has reduced most of the problems, the heat problem is still an issue.
Please feel free to contact us – we will be happy to advise you.
Qualitative aspects of light
The lighting concepts of exhibition designers and display case lighting designers are mainly based on three typical lighting techniques.
GENERAL LIGHTING:
Diffuse light
washes the space with homogeneous light and reduced shadows. It is often used for display cases with many objects and as an economical solution.
GENERAL LIGHTING:
Wallwasher
creates deep space and highlights the silhouette of an object, casting a shadow over the object itself.
GENERAL LIGHTING:
Spot light
washes the space with homogeneous light and reduced shadows. It is often used for display cases with many objects and as an economical solution.
Diffuse light
Wallwasher
Spot
Combination of wallwasher + spot
Combination of diffuse light + wallwasher + spot
In addition to light sources, reflective surfaces such as display case bases can be used to improve legibility by brightening shadow areas, especially when using spot lighting only. Choosing light colours will enhance reflection and using dark, light-absorbing colours and materials will reduce this effect.
For visual comfort, light sources should be out of sight to avoid disturbing direct glare. Hidden light sources can create magical effects through hidden reflective surfaces.
We are happy to work with and for you on these and other special applications.
The products
Luminaires, accessories, ballasts and light control units are supplied by a number of companies, with all components available in varying quality and aesthetics. Glasbau Hahn installs all brands specified by the lighting designer or the customer. Glasbau Hahn can also make suggestions, especially if higher quality or more cost-effective solutions are required.
Ballasts should be recommended by the luminaire manufacturer to avoid electromagnetic interference and flickering.
Lighting system features such as dimmability and controllability via Casambi-compatible systems for local dimming via APP or Dali-compatible systems for control via building management systems.
Various lighting control options are available to reduce the amount of light on objects, which have the same energy saving potential as dimming:
Sensor-controlled daylight level control, brightness level control, light duration reduction circuits, presence-based on/off circuits and temperature input control to reduce the load on the air conditioning system.
LED Lighting
Today, we use only LED light sources because of their sustainability, conservation and cost benefits.
The two most common types are direct LED lighting (linear light sticks or strips, light panels and spots) or fibre optic lighting with LED projectors.
Fibre optic lighting
Fibre optic lighting offers conservation benefits by separating the heat source from the light output, maintenance benefits as one light source supports more light outputs, and technical innovation is easy to implement as only the light projector needs to be replaced, unlike LED luminaires where each individual luminaire needs to be replaced. These are serious arguments when the life cycle of the showcase is 25 years. Disadvantages include a more complex installation, sometimes in conflict with the formal aspects of the showcase, and the fact that only LED projectors are dimmable, so there is no simple individual dimming of the light outlets. This can only be achieved through the more complex use of filters. And this is initially more expensive.
LED Luminaires
LED lighting dissipates heat from the circuit board through the heat sink and housing to the rear. If the light source is located in the display area, it may heat up by a few degrees, which will affect the relative humidity and is therefore not suitable for very sensitive objects.
LED luminaires should therefore be installed in areas or light boxes that are thermally isolated from the display area.
Accessories
All essential accessories are available for both systems to support the creation of customised refined high-quality lighting scenarios.
When creating lighting concepts and lighting solutions, we are happy to advise you on feasibility, costs, visual comfort and conservation aspects.
How to operate.
Best practice is to include a light designer in the planning of the lighting concept. But from our experience it is then important to finetune the lighting concept by creating a lighting mock-up to further refine their quality solutions. If the economic aspect is of outmost importance Glasbau Hahn offers standard lighting solutions for spot lighting and diffused lighting or its combination.