Theater Lighting Design

Theater Overview

A certain theater has been put into use for nearly 10 years, some of the lighting equipment is aging, and failures occur from time to time. The measured average illuminance is only 50 lx, which is far below the standard illuminance requirements. The thyristor dimming equipment is completely damaged, and it can no longer meet the needs of normal use. Therefore, the theater needs to be optimized and transformed to meet the needs of future development. The renovation design is based on GB 50034-2013 “Architectural Lighting Design Standard”. Determine the illuminance, lighting source, and type of lamps in different areas of the theater. Lighting arrangement and installation methods, etc. The Upgrading program selects high-power LED lamps to replace the original traditional lighting fixtures to increase the illuminance. And achieve energy saving, improve lighting quality and other purposes.

 

The lighting fixture comparison is shown in Table 1.

Table 1 Comparison of lighting fixtures

Original lamps	LED lamps
100W incandescent lamp	PFL-50-L
50W Ring Energy Saving Lamp	PFL-20-L

DIALux Software Simulation

DIALux is a simulation software that can simulate and calculate indoor and outdoor lighting, which provides more accurate reference information for the actual configuration of lamps. CAD files can be imported, modeling is fast, lighting design and simulation calculation requirements can be realized, and complete digital reports and three-dimensional renderings are provided.

Using DIALux to simulate tall space buildings (theaters) can improve the accuracy of calculations and obtain more optimized and reasonable design schemes, thereby improving the quality of the project.

 

In the LED renovation plan, the three-dimensional view of the theater space and the layout of the lamps can intuitively understand the layout and effects of the lamps in the theater. After many program adjustments, adjust parameters such as lamp power, and determine the lamp parameters and layout through simulation.

Lighting arrangement

 

The illuminance effect simulated by DIALux is shown in the figure below, which meets the lighting requirements of the theater.

Illumination effect simulated by DIALux

 

Comparison Between LED Lamp Solution and Traditional Lamp Solution

1) Comparison of light source performance

Basic performance

Table 2 shows the performance comparison of incandescent lamps, ring lamps and LED lamps.

 

Table 2 Performance comparison of incandescent lamp, ring lamp and LED lamp

index	incandescent lamp	Ring Energy Saving Lamp	LED Light
Wattage (W)	100	50	30
Luminate Efficiency (lm/W)	10~20	55~80	100
CRI (Ra)	>60	>75	>80
Lifespan (H)	1,000	10,000	50,000
Heat Generated	High	High	Low
Flicker Degree	NA	Yes	NA
Startup performance	Instant start	Poor starting performance, difficult to start at low temperature	Instant start
Light decay	High	High	Low

It can be seen that the performance of LED lamps is superior to traditional incandescent lamps and fluorescent lamps. The LED lamp has stable electrical performance, and the chip uses a wide voltage and wide frequency input. No flicker, can adapt to a wider range of voltage fluctuations. Therefore, the fluctuation of the mains power does not affect the LED lamps. The fluctuation of the power supply voltage will greatly shorten the service life of traditional fluorescent lamps and incandescent lamps, and cause stroboscopic flicker, which affects the quality of lighting.

LED lamps use high-efficiency constant current drive circuit, short power-on response time, suitable for frequent switching occasions. The service life has reached tens of thousands of hours under the condition of ensuring quality. Every time a traditional fluorescent lamp is started, the filament of the tube is impacted by high voltage, and the current at the start is 2 to 3 times the current during normal ignition, which accelerates the consumption of electron-emitting materials on the filament and shortens the service life.

Lighting control

Dimming of traditional lamps is difficult, and large-scale thyristor dimming equipment is required. The equipment is vulnerable and takes up space. The light source of the LED lamp is combined with the control and driving power supply, directly using 100V ~ 220 V AC power supply, and is controlled by the DMX 512 signal, no longer need the traditional thyristor dimmer.

Before the renovation, a dedicated dimming room was reserved on the 2F of the theater. The cost is high, the dimming operation is complicated, and it is completely damaged after less than 8 months of use. After the renovation, the LED lighting dimming loop control line is directly led to the audio lighting control room and connected with the dimming disc, which can quickly adjust the lighting brightness of the theater according to different application environments to obtain better use effects.

Comparison of economy and energy saving

★Lamp purchase cost

The comparison of lamp life and purchase cost is shown in the table below.

Table 3 Comparison of lamp life and purchase cost

Luminaires	Lifespan (H)	Unit price ($)	Number of replacements per year	Quantity	Cost per Year ($)
100W incandescent lamp	1,000	1.50	8.7	91	990.00
50W Ring Energy Saving Lamp	10,000	6.25	0.87	55	786.00
PFL-50-L(50w LED)	50,000	30.00	0.25	40	252.00
PFL-20-L(20W LED	50,000	20.00	0.25	50	185.00

It can be seen that the annual cost of the original plan is $8,247.00, and the plan after the transformation is $7,252. Therefore, although the initial purchase cost of LED lamps is relatively high, it is a more optimal choice from the perspective of long-term use.

★Lamp maintenance cost

The movie lighting is happy to switch on and off, the original equipment repair time, maintenance cost is high, and the lamps are installed on the horse track, failures and malfunctions, there are hidden safety hazards.

 

★ Simplified comparison

The calculation method of annual power consumption is based on the working hours of cinema lighting fixtures 4 hours a day and 120 days a year. In the original lighting plan, the annual power consumption was 1,296 kWh, and the electricity cost was $1 036.80. In the LED lighting retrofit plan, the annual power consumption was 624 kWh, and the electricity cost was $504.00.

 

★ conomic Comparative Analysis

By comparing the purchase cost, maintenance cost and electricity cost of theater LED lights and traditional lamps, it is guaranteed that the cost of using LED lamps is about 50% of that of daily lamps, and the effect is significant in terms of energy saving.

Environmental protection comparison

The LED light source is a green light source that emits pure color and does not contain ultraviolet and infrared radiation. At this stage, the fluorescent lamps and metal halide lamps used in large quantities on the market contain harmful heavy metal mercury. The production process and improper disposal of waste pipes will cause pollution to the environment.

Illumination measurement result

After the theater LED lighting renovation, engineers conducted field tests on the on-site lighting. The measured results of the illuminance after the transformation are shown in the table. It can be seen that the on-site illumination has been significantly improved. The light control is more convenient and meets the needs of different scenes. There is not much difference between the field measured data and the DIALux simulation results, which verifies the feasibility of the LED lighting retrofit scheme.

 

Table 4 Measured results of illuminance after renovation (lx)

Mode	Position	Test Point 1	Test Point 2	Test Point 3	Test Point 4	Test Point 5	Test Point 6	Test Point 7	Avg Lux
Full Lighting	1F Ground	355	351	372	373	362	342	363	360
	1F Seats	679	690	711	720	710	680	650	691
	2F Seats	481	489	460	500	470	496	486	483
80 % Lighting	1F Ground	275	288	290	287	287	276	280	283
	1F Seats	387	408	398	432	425	387	390	400
	2F Seats	391	404	404	406	402	401	395	400
50% Lighting	1F Ground	179	188	187	180	181	185	180	182
	1F Seats	227	245	261	251	243	250	232	244
	2F Seats	223	240	240	256	251	241	215	238

The effect of the theater LED lighting transformation is shown in the figure