Light museums galleries

Fördergemeinschaft Gutes Licht (FGL) provides information on the advantages of good lighting and offers extensive material on every aspect of artificial lighting and its correct usage. FGL information is impartial and based on current DIN standards and VDE stipulations.

Fördergemeinschaft Gutes Licht

Good Lighting for Museums,

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FREE-STANDING EXHIBITS REVOLVING EXHIBITION

ENTRANCE AREA EXHIBITS ON WALLS

EXHIBITS IN SHOWCASES

Contents

Cover photograph: Lighting creates visual

experiences in any exhibition Modulating

and accentuating the visual landscape, it

enhances the impact of a presentation

Lighting is vital for spatial impression and

enjoyment of art.

Visual experiences 1

The action of light 2

Exhibits in the limelight 6

Whether the focus is art or ence, technology or history, thepresentation needs to be ap-pealing, interesting and varied.And that is where lightingplays an important role: it cre-ates visual experiences in anyexhibition, it helps modulateand accentuate the visuallandscape, it enhances the im-pact of the items on display.The visual ambience must notcause fatigue On the contrary,

sci-it should stimulate – but notconfuse In large buildings, dif-ferentiated room design is also

a requirement

Light spacesLighting is vital for spatial im-pression and enjoyment of art.Different light colours andbeam spreads, different de-signs and arrangements of luminaires and lamps createdifferent lighting situations –light spaces – designed tomeet the relevant needs of theexhibition

Special attention needs to bepaid to conservation require-ments Light protection plays

an important role in any bition room

exhi-There is more to a museumthan just what it displays; it isalso a place of research,where collections are stored,preserved and managed Only

in the right lighting can

muse-um staff work effectively ing also draws attention to trip-ping hazards and reduces therisk of accidents So althoughthe lighting designer has agreat deal of freedom in exhi-bition rooms, functional lightingmust always be provided

Light-Visual experiences

Fig 1: The graphic above shows

a virtual museum: most of the space is occupied by the exhibi- tion area (blue), followed by the general public areas (red) and the rooms which serve as work premises (orange) The outdoor area (green) is surrounded by the building

The design and

configura-tion of exhibiconfigura-tion room

lighting depends on many

planning parameters

Fore-most among these is the

architecture of the building

with which the lighting is

required to harmonise

Oth-er factors are room

propor-tions, interior design, colour

scheme, available daylight

and, last but not least, the

nature of the exhibition The

way the ambience is

shaped by light and

shad-ow is a matter of

funda-mental importance

Room lightingLighting for exhibitionrooms in museums ismade up of diffuse and di-rectional light The relativeamounts and resulting mix

of the two types of light termines the harshness ofthe shadows cast by pic-ture frames and the three-dimensional impact ofsculptures and spatial ob-jects The diffuse and di-rectional light mix also de-fines the overall impressionmade by the room

de-A closely related matterhere is the distinction be-tween room and exhibitlighting The diffuse lighting

is almost all generated bythe room lighting, whichdetermines the distribution

of brightness and sets ing accents in the horizon-tal plane

light-Room lighting alone israrely enough to meet all

Exhibit lightingExhibit lighting uses hard-edged directional light toaccentuate individual items

on display As a generalrule, it needs to be supple-mented by softer roomlighting Exhibit lightingbased on spots alone isadvisable only where a par-ticularly dramatic effect isrequired

Otherwise, a stimulatingspatial experience is ob-tained with a mix of diffuse(room) and directional (ex-hibit) lighting

Diffuse lightingDiffuse lighting illuminatesroom zones or objectsfrom a surface that radiateslight in all directions At thesite of illumination, i.e inthe room zone or at theobject illuminated, the di-

rection from which the lightcomes cannot be clearlydetermined: the light flow-ing into the room and overthe objects is not direction-

al Where it comes fromvery many directions, i.e.where the radiant surface

is large, the lighting duces little or no shadow-ing

pro-Directional lightingDirectional lighting is gen-erated mostly by punctuallight sources – i.e lampsthat are small in relation tothe lighting distance – orspots of similar design Thelight falls directly onto theobject illuminated, striking

it, or parts of it, at an angledefined by the geometry ofthe lighting arrangement.Where the surface of theobject is uneven, clearlydefined shadows occur.These enhance the visualimpact of three-dimension-

al surfaces but can also be

a source of visual ence if they are too domi-nant or too large

interfer-The action of light

Light protection

Daylight and artificial

light contain rays which

may fade, dry out,

discolour or deform

exhibits Conservation

measures can protect

against this but only if

they are properly applied

and observed For more

about light protection,

see page 30

Route lighting

In some exhibition rooms,visitors are free to movearound in any direction Inmany others, however, be-cause of the nature of the ex-hibition or for organisationalreasons, they need to be ‘di-rected’ Luminaires whichhighlight routes without inter-fering with the display areas

on either side are a practicalsolution for this task Alsopractical – and stylish as well– is (additional) floor-levelorientation lighting, e.g withLED lighting strip

Photo 1: Ambience and the way

we experience a room are shaped by light and shadows and the way they are mixed Photo 2: Diffuse lighting is predominantly used for general room lighting.

Photo 3: Illuminating objects – exhibits are set off to dramatic effect by directional lighting 1

Diffuse/directional

lighting

In many applications, light

cannot be clearly defined

as wholly diffuse or wholly

directional This is the case

where the surface radiating

the light is neither large nor

punctual – e.g a spot with

a diffuser disc Depending

on the diameter of the disc

and on the lighting

dis-tance, shadows are

nar-rower or wider, harsher or

softer

Diffuse/directional lighting

also occurs where a

sur-face is illuminated or

back-lit to produce diffuse

light-ing and part of the light is

made to radiate in a

partic-ular direction and is thuspartially directional The di-rection from which the lightcomes can be seen on theobjects illuminated Howev-

er, the shadowing that curs on exhibits is lessclearly defined than if thelight were entirely direction-

oc-al The modelling is dered more subtle by thebrightening effect of the dif-fuse lighting component

ren-Diffuse/directional lightingcan also be produced, forexample, by linear lamps inappropriately designed lu-minaires Here, shadowingdepends on the position ofthe luminaire in relation tothe picture: wallwashers

wall, diffuse lighting for the room

Fig 3: Supplementary directional lighting for objects in the room

Fig 4: Indirect and direct components produce diffuse and directional lighting respectively

Fig 5: Solely directional light

with tubular fluorescentlamps mounted horizontally

or parallel to the upperedge of the wall producehard-edged shadows be-neath horizontal pictureframes, whereas the shad-ows cast by the vertical part

of the frame are barely cernible

dis-Avoiding cast shadowsDirectional light producesform shadows Where italso results in cast shad-ows on neighbouring ob-jects, the hard contours andobscure origin of suchshadows are disturbing

Cast shadows are avoided

by ensuring an appropriatemix of diffuse and direction-

al light, correct positioning

of the light source ing the directional light orappropriate positioning ofthe illuminated objects inrelation to one another

produc-2

3

The most important lightingsystems used in exhibitionrooms are:

 luminous ceilings withopal glass enclosure (dif-fuse light) or satinised andtextured glass (diffuse/directional),

 indirect luminaires fuse),

(dif- cove luminaires (diffuse),

 wallwashers (directional

or diffuse/directional),

 spot lamps

Luminous ceilingsThe idea of luminous ceil-ings stems from a desire toimitate daylight Luminousceilings deliver light which isparticularly suitable forpainting galleries – predom-inantly diffuse with an opalenclosure, partly directionalwith enclosures of sa-tinised/textured glass Theheat that is generated in anyluminous ceiling needs to

be dissipated or extracted

The light sources of choiceare tubular fluorescentlamps arranged according

to the structural grid of theluminous ceiling For gooduniformity, they should bespaced no further apartthan the distance to theceiling enclosure The size

of the luminous ceiling, its subdivision and the tran-sitions between ceiling andwalls need to suit the pro-portions of the room andthe nature of the objectsdisplayed

Luminous ceilings imitatingnatural daylight need to deliver a high level of lumi-nance: 500 to 1,000 cd/m2,ranging up to 2,000 cd/m2

for very high-ceilingedrooms Luminous ceilingsare especially suitable forinteriors with 6 metre ceil-ings or higher Where roomheights are lower, their lightcan dazzle because theyoccupy a large part of thefield of vision Where thelighting is dimmed for con-servation reasons or to re-duce glare, the luminousceiling loses its daylight

The action of light

Photo 5: Indirect lighting has

an impact similar to that of a luminous ceiling.

Photo 4: Luminous ceilings are particularly suitable for painting galleries The cove lighting provides additional brightness.

4

5

quality and looks grey and

oppressive All luminous

ceilings – including

day-lighting installations – need

achieved with indirect light

bounced off the ceiling and

upper wall surfaces into the

room This diffuse, uniform

light is predominantly used

in rooms where no daylight

enters It is produced by

suspended luminaires

radi-ating light upwards

In exhibition rooms, for

ex-ample, luminaires for

sus-pended power track

sys-tems are an option: they

are inserted in the track

from above while spots for

directional lighting are

ac-commodated in the lower

channel

Cove luminaires

The diffuse light of

lumi-naires installed in the

curv-ing transition between wall

and ceiling – the cove or

coving – is another indirect

lighting solution The cove

luminaires most frequently

used in modern museum

buildings are models withhousings which themselvesform the coving

The main direction of lightwith cove lighting is closer

to the horizontal than with aluminous ceiling and corre-sponds roughly to that ofperimeter luminairesmounted in continuousrows The light is largelyshadow-free Linear lamps– generally tubular fluores-cent lamps – are the mostwidely used light source

Excessive luminance at theceiling and on the upperpart of walls causes glareand interferes with spatialexperience This can occur

in coves where no stepsare taken to provide opticalcontrol – for example be-cause the existing cove of-fers no space for prisms orreflectors Where simplenon-overlapping battensare installed, disturbinglight-dark transitions arealso visible around the lam-pholders

WallwashersWallwashers are used as in-dividual luminaires or incontinuous rows Installedflush with the ceiling (or with

kick reflector protrudingfrom the ceiling) or mount-

ed close to the ceiling, theyshould illuminate the walls

as uniformly as possible

This task is performed byreflectors with asymmetricaloptics It is important to en-sure good shielding in thedirection of the observer El-ements on the luminaire formounting accessories –such as filters or anti-glareflaps – are useful

Favoured light sources forwallwashers include linearlamps: fluorescent lamps,compact fluorescent lamps

in elongated designs, linearhigh-voltage halogenlamps The diffuse/direc-tional lighting delivered bythe continuous rowarrangements that are pos-sible with these lightsources produces relativelydeep shadows, especiallyalong the horizontal edges

of picture frames

The directional light ered by individual lumi-naires with non-linearlamps, on the other hand,gives rise to additionalshadows along the horizon-tal edges of a pictureframe

deliv-Spot lampsReflectors in reflector lamps(used in luminaires with noreflector) or spots directmost of the light emitted bypunctual light sources in adefined beam direction.Spots and downlights withspot characteristics can befully or partially integratedinto a ceiling (or wall) asrecessed ceiling spots Sur-face-mounted ceiling spotsand downlights as well asspots for power track havevisible housings Elements

on the luminaire for ing accessories – such asfilters or anti-glare flaps –are useful

mount-Punctual light sources clude high-voltage halogenlamps and low-voltagehalogen lamps with andwithout reflector, incandes-cent lamps with or withoutchrome cap as well as met-

in-al hin-alide lamps

Photo 6: Wallwashers distribute their light asymmetrically Photo 7: The directional light of spot lamps raises the

brightness for exhibits – here with an appropriate beam angle for paintings.

Exhibits in the limelight

Medium-scale, large and

very large exhibits and the

light that falls on them are

seen to full effect only from

a distance This must be

borne in mind when the

ex-hibits are positioned

Viewing without

interference

To ensure that all exhibits are

shown to their best

advan-tage, neither the room nor

the exhibit lighting should

in-terfere with the visual task:

 There should be no

evocative shadows or

pat-terns of light on walls or

ceil-ing Such visual interference

definitely needs to be ruled

out for exhibition walls

 Reflections and

undesir-able shadows on pictures

and objects should be

avoided With direct lighting,

the way to guard against

this is to position luminaires

so that the distance from

the exhibit is around a third

of the height of the wall

 No cast shadows should

fall on neighbouring

ex-hibits

 A greater distance

be-tween wallwashers and wall

makes for better uniformity

but presents a risk of direct

glare The compromise

be-tween uniform illumination

and visual comfort: the

an-gle between luminaire and

wall down to the lower limit

of the presentation area

should be between 25 and

30 degrees (see Fig 6 + 7)

Reflectance in the room

The colour, pattern and

re-flectance of ceiling, walls

and floor affect the visual

impact of the exhibits and

the atmosphere of the room

How bright or dark walls

and ceiling can be kept –

i.e how high their

re-flectance should be –

pends crucially on the

de-sign intention It is not

pos-sible to make a general

rec-ommendation

What kind of light has

what impact?

An “exhibit in the limelight”

is (almost) always an exhibit

in directional light Whathappens when changes aremade in direction of lightand beam angle? What doobjects look like with andwithout bright surroundings?

What difference can naire accessories make?

lumi-Answers are found in thephotographs on page 7,where a portrait and a non-figurative painting are pre-sented as examples of two-dimensional pictures and afragment of an ancientsculpture and a red vase forthree-dimensional objects

Basically speaking, the pact of any change onthese relatively small ex-hibits is the same for large-scale pictures and objects

im-The only difference is thatthey need more light: high-

er power lamps or greaternumbers of spots need to

be used for illuminatinglarge objects A very largeobject, such as a car or aplane, can also be illumi-nated from several points

This makes for striking sual impact from variousviewing angles

vi-Text panelsPrinted information about

an exhibit is useful only if it

is legible – which is alwaysthe case with adequatelylarge black type on a whitebackground Where differ-ent lettering is required, itshould be tested for legibili-

ty in advance And alwaysremember: legibility is im-paired by reflections

C

B

A

1 m 1.6 m

30° spotlight opening angle x

70°

30°

100° critical vation zone for vertical illumi- nation

obser-Line of view- ing Edges of picture

3,30 (y = 1.65)

2,70 (y = 1.05)

x = y · tan 30° Room height spot/wallx = Distance2.7 m 0.60 m 3.3 m 0.95 m 4.0 m 1.35 m Line of viewing

Fig 6 + 7: Calculation of the optimal positioning of a luminaire for pictures on a wall – room height, observation zone, size of picture and optimal viewing angle (fig on left) are the parameters defining the optimal position of a wall-lighting luminaire The upper edge of the picture determines the spotlight opening angle (B: 30°, C: 60°) with a constant angle of inclination of 30° Angles less than 30° can result in reflections at the upper edge of the picture (critical observation zone) The mathematical formula for calculating the distance “x” between spotlight and wall for illuminating a picture with the height “y” is: x = y tan 30° (fig on right).

Photo 8: Higher power lamps or multiple spots are used for illu- minating large-scale objects

8

Spot with 15° beam angle and

Diffuse ambient luminescence

Spot with 15° beam angle and

soft focus lens

Spot with 45° beam angle and oval lens

Wallwasher with asymmetrical light distribution fitted with R7s halogen lamps (230 V)

Spot with 15° beam angle,

lighting from front, top, middle

Spot with 15° beam angle, ing from front, top, left

Spot with 15° beam angle, ing from front, bottom, left

light-Side lighting from right

20 19

18 17

Wallwasher with symmetrical light distribution fitted with R7s halogen lamps (230 V)

Showcases are miniature

exhibition rooms and the

exhibits they contain need

to be illuminated

accord-ingly – with diffuse or

direc-tional light In some cases,

illuminating and

accentuat-ing light may also be mixed

in glass display cabinets

The right light for the task

The type of lighting

re-quired depends essentially

on the characteristics of the

exhibits – on

three-dimen-sional form, structure,

sur-face gloss and

transparen-cy or colour

Most metal objects – gold

or silver receptacles, for

example – acquire a

fasci-nating beauty when they

gleam And that gleam

occurs when they are minated by punctual lightsources Under diffuselighting, the receptacles appear matt and lifeless

illu-For transparent or cent objects such as glassexhibits, the key to height-ening visual impact liesmore in modelling than ingleam The structure of surfaces – cut, etched orpainted – also plays an im-portant role here Depend-ing on the exhibit, the correct solution may be dif-fuse or directional lighting(through-lighting) or acombination of the two

translu-With directional lighting, visual impact is determined

by the angle of light dence Diffuse lighting is

inci-appropriate for coloured ortransparent materials such

as glass windows

Integrated lighting Small, shallow display cabi-nets (glass-topped desks)and high or box-shapedshowcases mostly have anintegrated lighting system

This has advantages:

 Fewer or no reflectionsoccur on the cabinet glass

 It is easier to avoid directglare for the observer due

to bright unshielded lightsources

 It is easier to engineerspecial lighting effects for adramatic presentation

In small display cabinets,exhibits are normally illumi-nated from the side In highshowcases, lighting fromthe cabinet roof is an op-tion Alternatively, objectscan be bathed in light frombelow from the base of thecabinet

In addition to the lightingintegrated in the showcase,separate ambient lighting isgenerally essential De-pending on the atmosphererequired and the illumi-nance permitted for conser-vation, the room lightingshould be just below the

level of the showcase ing or even lower Orienta-tion lighting which relies entirely on stray light fromshowcases and not on adedicated orientation light-ing system should not betoo low

light-Light protectionLight protection (see page30) is also an importantconsideration for showcaselighting – not least becauselamps in showcases are often closer to exhibits than

in exhibition rooms It mustalso be borne in mind thatthe enclosed space of ashowcase has its own microclimate

For the lighting, there arealternatives to the lampsused in the past: LEDs, forexample, which deliver abeam that contains no IV or

IR radiation, and fibre-opticlighting systems, which

Showcase lighting

Photo 25: Under the top-down showcase lighting, the suits of armour gleam in fascinating detail

Photo 26: LEDs for light tion – luminous diodes emit neither ultraviolet light nor heat

have a very low UV/IR

content Incidentally,

be-cause of their size, both of

these solutions are also

suitable for illuminating very

small display cabinets

For fluorescent lamps,

compact fluorescent lamps

and high-voltage and

low-voltage halogen lamps, the

same safeguards are

re-quired in showcases as in

large exhibition rooms

External lighting

Room and object lighting

outside showcases is

gen-erally provided by ceiling

lights This type of lighting

is particularly suitable for

all-glass cabinets and

shallow glass-topped desk

showcases for viewing from

above Daylight and

object-oriented room lighting

generally need to be

sup-plemented by accentuating

exhibit lighting Where

luminaires are arranged to

suit showcases, there is

little risk of reflected glare

Limiting reflections

Limiting reflected glare is

an important consideration

whatever kind of lighting is

installed for showcases

with horizontal and vertical

glass surfaces Effective

bright internal lighting thuspresent a lower risk

Reflections can also becaused by windows (daylight) Appropriate positioning of showcases

or daylight screening – e.g with vertical blinds –prevents this kind of re-flected glare

protection against reflectedglare is provided by non-reflecting glass

Reflections on horizontalglass surfaces occur lessfrequently if the glass is tilt-

ed towards the observer

How visible they are pends on the degree ofcontrast with the surround-ings, i.e the darkness ofthe showcase Light-coloured showcases with

de-Photo 27: The manuscripts in the showcase walls are uniformly illuminated from top

to bottom.

Photo 28: Reflection-free external lighting illuminates and highlights the books in the cabinets

Photo 29: Where luminaires are arranged to suit showcases, ceiling lighting is largely reflection-free

29

Exhibits which are not on

permanent display or which

go on tour are presented in

rooms for revolving

exhibi-tions Each new show is an

added attraction and draws

new visitors to see the

per-manent exhibition

To cater for a regular

change-over of exhibits,

lighting systems need to be

adaptable So very flexible

lighting is required It

should be noted, however,

that absolute flexibility –

enabling the lighting to be

as finely tuned for every

temporary presentation as

for a permanent exhibition

– is an unattainable goal

Flexible lighting

The general – diffuse –

lighting takes little account

of the positioning of

ex-hibits The flexibility of the

system depends on the

directional lighting

Particu-larly suitable solutions here

are furnished by power

track systems, in which

swivellable, rotatable spotscan be snap-mounted atany point Part of the powertrack installed should bemounted along the walls topermit gallery-style walllighting In the rest of theroom, rectangular or squarearrangements of powertrack make for greater flexi-bility than an arrangement

in just one direction

An alternative to powertrack are stationary gimbal-mounted spots These canalso be set at any angleand servomotors can beused for re-angling and focusing Gimbal spotlightsare not quite as flexible asspots on power track butthey permit a ceiling thatmakes a much more tranquil design statementthan one with power track

Realigning luminairesThe luminaires of a flexiblelighting system need to berealigned for each new revolving exhibition – if

necessary by experimentingand repositioning exhibits

This invariable calls for theuse of ladders and steps

For inaccessible locations,remote control spots arethe right answer

Taking account of daylight

Where revolving exhibitionsare staged in daylit rooms,daylight incidence and theposition of showcases inrelation to windows (seepage 9) must also be takeninto account To maximizethe scope for catering toexhibition requirements, it

is best to ensure that daylitrooms can be fully dark-ened More informationabout daylight is found onpages 22/23 Facilities fordarkening rooms can also

be useful for light tion; for information aboutthe light protection require-ments of exhibits – whichnaturally also need to bemet in revolving exhibitions– see pages 30–33

protec-Mobile spotsWhere mobile partitions areused for presentations, mobile spots fastened tothe partitions by clamps orscrew mountings are an alternative to spotlights onpower track So that powercables to spots do not present a tripping hazard,rooms for revolving exhibi-tions should be providedwith power points in thefloor

Revolving exhibitions

Photo 30: The light of the gimbal-mounted spots is focus- able

30

Photo 31: Power track is integrated in the ceiling grid construction to accommodate the spotlights for the exhibit lighting.

Photo 34: The spotlights need

to be repositioned for every new revolving exhibition

Photo 32: Power track integrated

in the ceiling makes it possible

for spots to be positioned in

flexible arrangements

Photo 33: High illuminance

where required – each

luminaire features four

gimbal-mounted spots

32

The entrance area is the

calling card of the

estab-lishment It shapes visitors’

first impressions, its design

can overcome fear of

crossing the threshold A

harmonious lighting

atmos-phere sets the scene for a

friendly reception Foyers

also serve a functional

pur-pose: they lead into the

in-terior of the building

Harmonious lighting

To meet these ments, the lighting needs

require-to incorporate a mixture of direct and indirect light –delivered by a combination

of lighting systems sign ed to cater for everylighting task: the uniformgeneral lighting providessecurity and facilitates ori-entation, accentuating light

de-on ceiling and walls makesthe visual impact less severe Direct or direct/in-direct luminaires with efficient fluorescent orcompact fluorescent lampsare the most widely usedlight sources for the gener-

al lighting; wall luminairesfor indirect lighting formpart of the accent lighting

In the entrance zone, ple step out of bright day-light into a darker building

peo-or out of night-time ness into a brightly lit interi-

dark-or To enable their eyes toadjust to the change inbrightness level, adaptationzones are recommended

During the day, the ate entrance area needs to

immedi-be particularly brightly lit;

at night, the illuminance inside the building shoulddecrease towards the exit

The calling card role of afoyer makes it an interest-ing place for special archi-tectural features – featureswhich lighting and lightingcharacteristics should underline For high ceilings,for example, high-intensityspots with high-pressuredischarge lamps are re -commended As pendantluminaires with direct/indi-rect light distribution, theyemphasize the height of the room Moulded plasterceilings, columns or galleries can be very effec-tively stressed by accentu-ating light

Guiding lightCorridors, staircases andlifts connect the entrancearea with the deeper recesses of the building

If they are significantlydarker than the foyer, theycan be off-putting To avoidthis tunnel effect, the illumi-nance realised should

either be the same or duced very gradually instages DIN EN 12464-1stipulates a minimum of

re-100 lux illuminance for circulating areas such ascorridors

A route guidance systemprovides an effective addi-tional orientation aid for visitors To ensure reliableguidance, it should includebright information panels orback-lit signs with a clearmessage

Safe lightThe risk of tripping onsteps and stairs is reduced

by good lighting The minance should be at least

illu-150 lux (DIN EN 12464-1)

As it is generally more dangerous to fall downstairs than to trip on theway up, it is particularly important that the lightingshould ensure that treadsare clearly discernible fromabove In addition, lightfalling from the upper land-ing makes for short soft-edged shadows Thetreads can thus be clearlydistinguished; each one isreadily identifiable

Floor-level orientation lighting provides added security Wall lights at theside of the stairs castingdirect light onto treads are

a solution here LED nology offers a new alter-native, e.g with luminousdiodes set into risers LEDsare also used for illuminat-ing banisters

tech-Foyers, corridors, staircases

Photo 35: Distributor role – foyer and corridors provide both

a physical and optical link with the deeper recesses of the building

35

Photos 36 and 37: The entrance area shapes first impressions Harmonious lighting makes for

a friendly reception

Photos 39 and 40:

Corridor lighting provides guidance for visitors and makes their route safe Minimum illuminance: 100 lux.

Photo 38: Light in banisters –

LEDs make it possible

38 37

40 39 36

An exhibition may include

video installations or

pre-sentations on large screens

or monitors of various

sizes It may also include

audio exhibits, i.e

record-ings of voices, sounds or

music

Reflected glare is

annoying

The lighting needs to cater

for the use of audiovisual

media Because reflected

glare on screens is very

annoying, highly directional

lighting should not be

in-stalled in the vicinity of

monitors High luminance

from neighbouring

exhibi-tion areas has the same

dazzling effect; stray light

from such sources should

also be limited

For audiovisual

presenta-tions, lighting should

nor-mally not be too bright –

neither for visual perception

nor for the perception of

sounds on which visitors

need to concentrate Where

presentations are

interac-tive, however, it is important

that controls such as

but-tons and their labels should

be easy to identify The minance of the additionallighting provided for thepurpose and its radiance inthe direction of the screen(reflected glare) and theoperator (direct glare) mustnevertheless be limited sothat they do not interferewith visitors’ perception ofthe presentation

illu-Computer roomWhere computers andmonitor screens are not in-tegrated in the exhibitionbut installed in a separatecomputer workstation room,

it is advisable to light thatroom as if it were an office(see page 19) If the timevisitors spend in the room

is kept short – for example

by putting a limit on themaximum length of stay –the lighting concept of theexhibition can also beadopted here even if itmeans a lower lighting level Having said that, therisk of direct and reflectedglare must always be ruledout

Audiovisual media

Photo 42: In a separate computer room, the rules of office lighting apply.

Photo 43: Feeling, hearing, seeing – all the senses are involved in experiencing the exhibition.

Photo 41: Audiovisual media can form part of an exhibition.

Catering for them calls for lighting incorporating no highly directional light, delivering illuminance tailored to presentations and providing adequate light for the use of controls.

41

42

43

Virtually every type of event

takes place in a lecture

room; certain guided tours

also start and end here The

room should therefore be

furnished and equipped as

a multifunctional facility –

with lighting installations

de-signed to create the lighting

conditions needed for all

the relevant occasions, thus

the different lighting

situa-tions presented by events

The first requirement is that

luminaires should be

grouped on separate

switching circuits because

the individual lighting

situa-tions – e.g “reception”,

“lecture” or “presentation” –

call for different system

set-tings One luminaire group

may be left switched off,

for example, while a

sec-ond is activated and a third

is dimmed

The task of lighting control is

performed via a simple

con-trol unit or – in larger rooms

– by a lighting management

system With lighting

man-agement, programmed

light-ing scenes can be adapted

to indi vidual conditions

with-out altering the

program-ming Cross-fade times can

be set as required on a

scale from one second to

several minutes Most

light-ing management systems

also offer the option of

incor-porating window darkening

and sunshade settings into

programs

One lighting control system

recommended for lecture

rooms is the DALI®system

(Digital Addressable

Light-ing Interface) with its

stan-dardised digital interface

Its key advantages are that

it has few components,

requires little wiring and is

Accent lighting essentialApart from having a func-tional role, lighting is also

an element of interior sign Accent lighting, for ex-ample, is essential in aprestigious lecture room

de-Numerous punctual light

sources, indirect lightingcomponents emphasizingthe architecture of the roomand planar or directional il-lumination of pictures andwall areas produce anagreeable effect For thelighting situation

“reception”, general and accent lighting should beclosely coordinated andprogrammed to be activat-

ed together

Lecture room

Photo 45: Lecture room lighting

is multifunctional lighting designed to create tailored lighting conditions for different situations.

Photo 44: “Film presentation” and “lecture” are the two lighting situations most frequently found.

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45

Library lighting has several

functions: it helps us get

our bearings, helps us find

the literature we require,

facilitates reading and

cre-ates a peaceful to subtly

stimulating atmosphere

The basis for planning is

DIN EN 12464-1 As a

general rule, the more

demanding the visual task,

the higher the lighting

re-quirement The illuminance

required for circulating

areas, for example, is 100

lux, for shelving systems

200 lux Reading areas,

however, call for 500 lux

Fast orientation

The general lighting – with

additional route marking

and identification of exits –

needs to permit fast

orien-tation and provide

guid-ance around the rows of

shelves Direct/indirect

lighting produces an

agreeably bright ceiling

and prevents the so-called

“cave effect” that can easily

occur in parts of a library

Where direct lighting

com-ponents are kept small,

annoying reflections

(reflected glare) on glossy

paper are also reduced

Suspended luminaires for

tubular fluorescent lamps

are the most widely used

here, along with luminaires

for metal halide lamps in

high-ceilinged rooms

Vertical lighting

components

Bookshelves and

bookcas-es should be well

illuminat-ed over their entire area

Vertical components need

to reach to the lowest shelf

to enable titles on book

spines to be read with

ease from a reasonable

distance Wallwashers with

asymmetrical beams are

particularly suitable for this

lighting task Lamps with a

good colour rendering

index (Raⱖ 80) ensure

that books can be easily

identified by the colour and

design of the spine, which

are often used as search

criteria

Reading desks requirebrighter lighting Wheredesk luminaires are used tosupplement the generallighting, visitors can raisethe lighting level to suittheir personal requirements

Library

Photos 47 and 48: Wallwashers with asymmetrical beams illuminate shelves – from the ceiling (47)

or as integrated shelf luminaires (48)

Photo 46: Helping visitors get their bearings, facilitating reading, creating a peaceful to subtly stimulating atmosphere – these are the tasks addressed

by library lighting

46

48 47

Some museums have

study rooms, which offer

more peace and quiet than

reading desks in a library

Here, students and others

with special interests can

consult not only books but

also exhibition and archive

documents

Exacting visual tasks

Even if a study room is not

equipped with computers,

the lighting should cater for

monitors because nearly

anyone researching a

sub-ject today has a laptop at

hand Working at a

com-puter, reading and writing

are demanding visual

tasks, for which DIN EN

12464-1 sets out a minimum

of 500 lux illuminance

Be-cause glare impairs visual

performance and causes

visual discomfort, care

needs to be taken – as in

an office or at any other

VDU workplace – to ensure

that neither direct nor

reflected glare occurs

Solutions suitable for the

direct lighting include

pen-dant luminaires – mounted

singly or in continuous

rows – with high-grade

reflectors and louvers and

downlights with similar

optical control elements

Adjustable lighting level

A particularly high degree

of comfort is offered by

lighting systems in which

stand-alone luminaires can

be dimmed or

supplemen-tary desk-top reading lights

switched on to tailor the

task lighting level to

indi-vidual requirements With

fluorescent lamps or

com-pact fluorescent lamps

operated by (dimmable)

electronic ballasts (EBs),

study room lighting can

also be particularly

eco-nomical

Study room

Photo 49: Daylight or artificial light enters the study room as indirect light from the light wells Downlights along the sides of the room provide supplementary lighting

Photo 50: The luminaires for fluorescent lamps are mounted

on power track to radiate light upwards or downwards

They provide indirect and direct lighting

Photo 51: These desks are used mainly by students 500 lux illuminance is provided for reading and writing tasks

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50

51

Cafeterias and museumshops are attractive places,especially at the end of amuseum visit The culinaryofferings are welcome andmany people buy the merchandise on sale assouvenirs or gifts

Cafeteria lightingFor cafeterias, differentiatedlighting with various room-structuring systems is rec-ommended: e.g pendantluminaires for tables, wallluminaires and downlightsfor a moderately higherlighting level, downlightsand spots for accent light-ing Depending on the sizeand design of the cafeteria,

a single lighting systemmay be enough

The range of design tions for catering establish-ment lighting is almostendless Limits are reachedonly where visual perfor-mance and visual comfortare significantly impaired,which means that glaremust always be avoided

op-Harsh shadows are alsobad because they interferewith facial recognition

In terms of brightness, vice areas in a cafeteriacan keep a low profile –with one exception: thefood counter and any otherareas where food and drinkare displayed or on saleneed to be more brightly litthan the rest of the room.DIN EN 12464-1 stipulates

ser-200 - 300 lux illuminancehere This helps guests get their bearings and facil-itates the visual task ofchoosing food

Sales lightingCapturing the attention oftoday’s visually spoilt consumer calls for cleverlydesigned sales presenta-tions The spectrum of customised solutions is aswide as the range of modern lamps, luminairesand spots For a museumshop, the design challenge

is to achieve optimal mony between the struc-ture and furnishings of theroom and lighting systemsdesigned to suit the mer-chandise on sale

har-A distinction needs to bemade between generallighting – “viewing light” –and accent lighting –

“display light” – for shelves,walls or special offer pre-sentations on the salesfloor The rule of thumb forthe right mix is: the moreupmarket the range, themore stylish the lightingand the greater the impor-tance attached to differ -entiated accent lighting

The overall impressionmade by graduated bright-ness levels determineshow stimulating customersfind the sales(room) atmosphere However, cau-tion is required: excessivedifferences in brightnessplace too much strain onthe eyes of shoppers andstaff Detailed information

is provided in FGL booklet

6 (see page 45) onsalesroom and shop win-dow lighting The relevantstandard is DIN EN123464-1

Cafeteria, museum shop

Photo 53: The scene is dominated by the rows of small punctual light sources.

Photo 54: Accentuating light with graduated brightness levels creates a stimulating sales(room) atmosphere.

Photo 52: The general lighting casts a discreet diffuse light.

52

53

54

Workplace lighting is

need-ed for rooms which are

not open to the public and

where the lighting caters

solely for the visual tasks

performed by the people

who work there These

rooms are essentially

offices, e.g administration

areas, workshops and

storage facilities such as

warehouses, depots and

archives

Office lighting

The first requirement for

vi-sual performance and vivi-sual

comfort is an adequate level

of lighting For compliance

with DIN EN 12464-1,

illumi-nance in the task area must

be no lower than 300 lux

The standard makes a

distinction between

room-related, task area and work

surface lighting (more

infor-mation in FGL booklet 4,

see page 45)

The most popular office

lighting solution is based

on pendant luminaires or

standard-alone luminaires

for direct/indirect lighting,

which most people find

agreeable The alternative

– direct general lighting

with recessed or

surface-mounted ceiling luminaires

or pendant luminaires with

specular louvers – is

ap-preciated especially for its

uniformity

One of the most important

quality criteria, particularly

for VDU workplaces in an

office, is direct and

reflect-ed glare limitation by

appropriate positioning of

luminaires, desks and

monitors Where accent

lighting is provided by wall

luminaires or showcase or

picture lights, care must be

taken to ensure that

dis-turbing reflected glare is

avoided

Workshop lighting

For compliance with DIN

EN 12464-1, what applies

to offices – see above –

basically applies also to

workshops Regardless of

the type of work performed,

the illuminance in museumworkshops, including training workshops, should

be 500 lux The finer andmore critical the visualtask, the more light isneeded For this, supple-mentary workplace lumi-naires can be used to raisethe illuminance at theworkpiece A suitable solu-tion for the general lighting

is task lighting with naires for fluorescentlamps arranged parallel

lumi-to windows, preferably withlight falling on the work-bench from the side

Generally speaking, it isadvisable in workshops toinstall luminaires with ahigher degree of protec-tion A luminaire protected

to IP 43, for example, isprotected against theingress of solid particles

⬎ 1 mm and againstspraywater, while an IP 54luminaire is dustproof andprotected against splash-water

Storage room lightingThe kind of work done instore rooms, depots orarchives requires less lightthan craft activities Never-theless, relatively high illuminance is important forhandling small items instorage and for all work involving reading tasks (labelling items for storage,completing forms) If thereading and searching task

is focused on shelves – i.e

a vertical plane – as much

as 300 lux vertical nance may be required

illumi-Higher illuminance than the

100 lux stipulated in DIN

EN 12464-1 facilitates reliable visual perception,heightens concentration,helps to avoid mistakesand guards against acci-dents Luminaires for fluo-rescent lamps are the mostsuitable option for rooms ofnormal height; luminaires with high-pressure discharge lamps are the solution recommended for interiorswith higher ceilings

Workplace lighting

Photo 55: In offices, light must cause neither direct glare nor reflected glare on screens

Photo 56: The finer and more critical the visual task, the more light is required

Photos 57 and 58: Storage facilities require a minimum of

100 lux to be compliant; higher illuminance levels are better.

standard-55

56

58 57

Whether sculptures or stallations, some works ofart are intended to be exhibited outdoors whileothers may become candi-dates for outdoor displaybecause of their size Forthe majority of such ob-jects, an inner courtyard orsmall patch of garden isnormally enough

in-Interplay of light andshadow

Outdoor illumination atdusk or at night basicallyhas the same effect as illu-mination with directionallight in an exhibition room(see pages 2, 6) But it alsogives exhibits an appear-

ance they do not have indaylight: the artificial light-ing creates new structures,reinventing the object in agame of light and shadow

The best way to determinethe perfect location for amobile spotlight or flood is

to conduct trials – with light from below, from be-low and from the side, from the side, from above,from above and from theside, or even bounced offanother surface Every solution has a charm of itsown For lighting from below, recessed groundfloods are the alternative to

spots Highly focusedbeams are by far the firstfavourite; with illuminationfrom below and some other configurations, thebeam spread can begreater

Avoid glare

If the idea is to illuminatethe whole object, lightsneed to be set at a greaterdistance than for highlight-ing details When position-ing spots and floods, it isimportant to make sure that observers will not bedazzled, at least in theprincipal viewing direction

To achieve the same ing impact with differentobjects, the general rule is:the darker the object andbrighter the surroundings,the more light is needed.Ultimately, however, even illuminance is a matter oftaste and design intention

light-Outdoor exhibits

Photo 60: Light from below – the stationary recessed ground floods are installed in groups Photo 61: Facade painting – floodlighting creates a splash of colour at night.

Open air museum

Open air museums are

a showcase for historical

buildings and

complex-es, either in their original

state or reconstructed

They close when it is

dark, so artificial lighting

is generally installed

only inside the buildings

– if possible without

spoiling the impression

of a time before the

ad-vent of electricity Where

an open air museum

stays open after dark,

path lighting is also

Buildings bathed in light

impact at night because of

their architecture Where

facade lighting makes this

visible, decorative night

images are created

Illumi-nated advertising signs

and frontal floodlighting

also help shape a museum

facade lighting imbues a

building with a unique

quality – and enhances the

area around it at the same

time

Illuminating the entire

building has a long-range

impact; harnessing light

to emphasize only

architec-tural details heightens its

presence for passers-by

Where the principal

view-ing direction and the

direc-tion of illuminadirec-tion are not

identical, light-dark

con-trasts create a

three-dimen-sional effect: an angle of

around 60 degrees to the

viewing direction is right for

plain or fairly plain facades;

for more detailed or ornate

facades, the angle can be

smaller

Ensuring floodlights are not

installed too close to the

building avoids excessively

deep shadows Beams

should not cross or

shad-ows will be too light

Floods with a long-range

impact should be

posi-tioned high and mounted

as inconspicuously as

possible High-pressure

sodium vapour lamps

un-derline the character of

warm colours and

materi-als; for cooler-looking

surfaces, metal halide

lamps are a suitable

solu-tion Illumination is also

possible with wall

lumi-naires integrated in the

facade and recessed

ground floods positioned

directly in front of it

The illuminance required isdetermined by the colourand thus reflectance of theilluminated building (build-ing luminance) and by theambient brightness: thedarker the building andbrighter the surroundings,the more light is needed

Precise planning avoidslight emission into the sur-rounding area

Alternatives to classical illumination are presented

by fibre-optic lighting tems and LEDs, with whichfacades or parts of facadescan be bathed in dynamicchanging coloured light

sys-Another possibility is facade design based onactivated (and controlled)interior lighting

Other forms of illuminationFacade lighting is normally

a discrete design element

However, illuminated nage – e.g the name of themuseum in luminous letters– needs to be planned

sig-to suit it To achieve the sired effect, any additionalsignal lighting, such asfloodlighting for flags orbanners, needs to be coor-dinated with the facadelighting

de-In other outdoor areas, tractive scenes are alsocreated by illuminatingtrees or other vegetation

at-The rules to be followedhere are the same as foroutdoor feature lighting(see page 20) If the facade

is also illuminated, lightsshould only be trained onplants well away from thebuilding

Night scenes

Photos 62 and 63: Light turns facades into eye-catchers, enhances the building and gives it a unique quality.

Photo 64: The LED semicircle

on the facade of the Buhlsche Mühle event centre in Ettlingen symbolises the millwheels that turned here in the past

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63

64

Interior lighting with daylight

is an architectural

chal-lenge that absolutely must

be addressed and resolved

at the early design stage of

a new building Conditions

for harnessing daylight

can rarely be created later

and system modification is

difficult Daylight planning

is a matter for experienced

professionals

Daylight museum

Public museums built in the

first half of the 19th century

had to rely on daylight

From early times, architects

incorporated skylights to

harness it: in 1789, the side

windows of the Salon

Carée at the Louvre in Paris

were bricked up to enable

all the wall to be used for

exhibits

For a long time, despite

the availability of artificial

lighting, every new museum

was built as a daylit facility

But that changed in the

1950s and ’60s when it

was realised how much

damage daylight can do,

especially to paint and

other organic materials For

some time after that, all

new museums were built

with rooms without

win-dows

Today, our knowledge of

lighting engineering

cou-pled with modern control

and regulation technology

makes it possible for

daylight to be precisely

di-rected and dosed So once

again daylight plays a

major role in museum

con-struction and design

Skylights

Skylights are classic

day-lighting elements for picture

galleries They provide

uni-form, diffuse lighting

Be-cause the light is admitted

over a large area, the

shad-ows produced are soft

The incident daylight that

passes through a skylight

reaches nearly every part of

the room, including

free-standing display cabinets,

sculptures and partitions

Because no windows arepresent, more wall space isavailable for paintings

There is also no problemwith reflections on exhibi-tion walls due to incidentdaylight from the side

With large skylights, come interference may occur and needs to betackled by positioning theskylights appropriately andproviding for precise opti-cal control There is a risk,for example, of light being

unwel-unevenly distributed overthe walls In rooms withdark furnishings, in particu-lar, the vertical illuminance

at eye level is often too low The contrast betweenwall and ceiling brightnesscan cause glare And evenwith light incidence fromabove, reflections can

sometimes occur on tures on the wall

pic-Direct sunlight must always

be “locked out” But lightprotection is not alone inpresenting high require-ments: what all modernskylight solutions have incommon is that they areexpensive to design andconstruct for daylight direc-tion, control and filtering

The use of skylights to ness daylight is confined tothe upper storeys of a

har-building or calls for storey design Skylights are

single-no substitute for the visualcontact with the outsideworld provided by windows

WindowsOutsized windows are notnecessarily a suitable alter-native to skylights and not

actually the right tool formaking maximum use ofdaylight On the otherhand, there are many waystoday to direct daylight and

“lock out” direct sunlighteven in rooms with lateralwindows Having said that,these non-transparent systems do not fulfil the requirement met by day-light museum windows in making diurnal and sea-sonal change – as well asthe vicissitudes of theweather – a visual experi-ence

Windows reduce theamount of wall space forexhibits Undirected andunfiltered incident daylightcan give rise to reflections

be coordinated The

rea-Daylight

Daylight has considerable damage potential Both daylight and artificial light contain rays which maycause exhibits to fade, dry out or become discoloured

or deformed if exposed to the light for long periods

But daylight is certainly the more dangerous This isconfirmed in the art history publication “Über das Licht

in der Malerei” (Wolfgang Schöne, Berlin 1993), which,when considering light sources, focuses almost exclu-sively on daylight Few pages are devoted to artificiallighting

Information on light protection is found in this booklet

65