Lighting and Acoustics of Cinema Halls (Auditoriums)

• Ceiling mounted lighting fixtures in a circular pattern. 
• Central light fixture with pasters on the walls.

• Ambient lighting has been used to highlight the entrance by use of recessed halogens (50 w).
• The circular nature create a sense of movement towards the staircase.
• Accent lighting has been used to highlight the posters.

LIGHT QUALITY ON STAIRCASES

QUALITATIVE FEATURES ON STAIRCASES

• Staircases are adequately lighted with a lot of variation in color and type of lighting used.
• All the lighting fixtures are ceiling mounted and recessed or hidden .
• Landings have been separately lighted.

• A transition state has been created on each landing by the use of yellow light fixtures .
• The stairs have been lighted with white light .
• Hidden lighting fixtures have been used at certain points to break the monotony of the ambient lighting.

LIGHT QUALITY IN CORRIDORS

QUALITATIVE FEATURES IN CORRIDORS

• One experiences variations in the intensity of light as we move towards the entrance .
• The side corridor is dimly lighted , the lux level in the front corridor is comparatively higher.

^{Front Corridor}

^{Side Corridor}

• The changes in the lux levels has been done purposely to accentuate the feeling of being closer to the auditorium.
• White light is used in the front corridor to create a soothing environment and to reduce the anxiety level while yellow light has been used in the side corridors.
• All fixtures are ceiling mounted , recessed halogens (50 w)

LIGHT QUALITY IN THE FOYER

QUALITATIVE FEATURES THE FOYER

• The main foyer is highly illuminated by the use of wall and ceiling lighting fixtures.
• Variation in the light intensity can be seen in different parts of the same space .
• The food joints have been very brightly illuminated.

• Ambient and accent lighting has been provided which also take care of the task lighting.
• Chandelier has been placed in the center with ceiling mounted halogens alongside .
• The food joints have been over illuminated shifting  the focus towards it.
• The reflective nature of the walls , floor and the ceiling helps creating a soothing environment.

• There are two types and color of light that have been used in the foyer categorizing different functions.

• Although the foyer has been adequately lighted , the lighting quality produced by the chandelier creates a different ambience within itself . 
• Accent lighting has been used to accentuate the entrance to the auditorium in the same space but with different color.

LIGHT QUALITY IN WAITING LOUNGE

QUALITATIVE FEATURES IN WAITING LOUNGE

• Each sitting space has been highlighted with white light 
• Rest of the circulation space has been dimly illuminated with diffused yellow light.

• The variation in the light quality is clearly visible within the sitting area and the way the ambient (diffused) and accent lighting has been used , it creates a separate enclosure within itself without any physical demarcation.

LIGHT QUALITY IN WALL DISPLAYS

QUALITATIVE FEATURES IN WALL DISPLAYS

• Various type of lighting fixtures have been used for accent lighting of the wall displays in relation to the surrounding environment.

• Wall mounted fixtures have been used to focus on the displays .
• Different color lighting has been used for getting different effects for the displays.
• Yellow light has been used to provide depth to the displays
• White light has been used to achieve greater clarity.

ACOUSTIC GENERAL

• Acoustic planning should ensure that optimum audible conditions are created for listeners in room where speech and music are to be carried out.

• Two important factors considered in acoustic planning are :
• Reverberation time: time taken for the decay of a noise level of 60db after the sound source has been turned off.
• Reflections as the consequences of the primary and secondary structure of the room.

ACOUSTIC CINEMA

• Neighboring auditoriums should be separated with partition walls of approximately 85 db 18-20000 hz.

• Acoustic deflecting surfaces on the ceiling with low acoustic delay difference time.
• The reverberation time can increase with increasing room volume and decrease from 0.8-0.2 secs from low to high frequency.
• The rear wall behind the last row of seats should be sound absorbent to prevent echo.

ACOUSTIC TREATMENT DONE IN AUDITORIUM

ACOUSTIC TREATMENT

• A double layered gypsum board(2 x 15 mm thick) for false ceiling with 100 mm thick fiber glass(32 kg/cum) .

• For walls fiber glass(32 kg/cum) of 100 mm thickness and black tissue facing is supported in 100 mm GI stud frame work@610mm c/c with chicken mesh on both sides of insulation with air gap.
• The side walls have been treated with 100 mm thick fiber glass (12 kg/cum ) supported in 100 mm GI stud framework @ 610 mm c\c with chicken mesh for air gap and finally fixing 2 layers of gypsum board ( 15 mm thick ) over GI frame work.

• The side walls above 2400 mm have been treated with 50 mm thick fiber glass (32 kg\cum) with black tissue facing supported in 48 mm GI stud framing @ 610 mm c\c with chicken wire mesh.

• Fix 100 mm thick acoustic panels comprising 100 mm thick fiber glass ( 80 kg/cum ) wrapped with acoustically transparent fabric supported in 100 mm GI stud framework with one side chicken wire mesh & other side finished with perforated GI sheet. The panel is to be mounted on single layer of 15 mm thick gypsum board fixed on the wall with GI section.

CONCLUSION

• As the building has been renovated and converted into a cineplex , as expected it has not been given those bright and vibrant lighting as is seen generally in other cineplexes , rather out here the lighting is very subtle and classic sort , which has been done on purpose as all the interiors of the building are done in the classic style.
• Being a cineplex one of the main concern for the people running it was  the acoustics of the building , which they have taken lots of pain to make efficient.