Parabolic aluminized reflector light
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A parabolic aluminized reflector lamp (also PAR light or simply PAR) is a type of lamp that is widely used in commercial, residential, and transportation illumination. Usage includes locomotive headlamps, aircraft landing lights, and residential and commercial downlights ("cans" in the U.S.). They are identical in principle to sealed beam automobile headlights.
This article covers only their use in stage lighting. The lamps and their fixtures are widely used in theatre, concerts and motion picture production when a substantial amount of flat lighting is required for a scene.
They are frequently used in patterns of multiple lights such as 3 by 3 (known as a "nine light") when large areas are to be lit.
In situations where sunlight or other specular light is available, a white foam reflector is often used to accomplish the same effect as a PAR array.
PAR cans are being replaced in some applications by LED PAR cans, which use less electric power and produce a wide array of colors without the use of color filters.
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[edit] Construction
PAR lights possess a lens and reflector that are integral parts of the lamp, the position of which cannot be altered relative to the filament. A notable exception is ETC's Source Four PAR, which uses the same halogen lamp as their Source Four ERS. In this case, the lens is a separate piece from the lamp. The relative position of lamp and lens remains unalterable.
In PAR 64s, Raylite reflectors and two pin base lamps are often used as a cheaper alternative as the lamp is replaced but the reflector remains. Lamps such as the 500 watt A1/244 can be as much as half the price of the sealed beam units. Par 64's also often run at 120v, in two-pair series channels, with a "y" Splitter at the dimmer. Narrow, medium and wide Raylite refectors are quite readily available. The two-blade (pin) Mogul lamp connector need not be replaced — this is integral to the Raylite reflector, Although some Raylite reflectors have "tails" which then require connection to the mains flex with the use of a ceramic connector block (ideally fixed to the can's body).[1]
[edit] Effects
The sealed beam lamp produces an intense oval pool of light with unfocused edges. The only focus adjustment is a knob that allows the lamp/lens unit to be rotated within its casing, thus changing the orientation of the oval. With some models this control is via the mogul ceramic connector which connects directly to the Mogul prongs of the lamp. With the SourceFour PAR, the interchangeable lens is what is rotated. The type of lamp may be changed, and options include extra-wide flood (XWFL), wide flood (WFL), medium flood (MFL), narrow spot (NSP), and very narrow spot (VNSP).
These types of instruments come in varying diameters, the most common being designated PAR56 and PAR64. The number indicates the diameter of the housing in eighths of an inch (so a PAR64 is eight inches (~20 cm) in diameter).
[edit] Uses
PAR lights are often used in theatrical or live music shows. Commonly they are used to generate colours by fitting them with colored sheets called gels. The cans are arranged into rows of different colours and identical rows placed on different sides of the stage. Due to their affordability, they are ideal for color washes in several different colours. However, because of the lack of control over the beam diameter, shape and sharpness, PARs are rarely used as front of house lights or general wash lights but can be used for special effect lighting such as lighting from directly above or from extreme angles. If used cleverly, par cans can provide low budget productions with good effects.
[edit] Variations
[edit] Diameter
- 64 (8" or 20 cm)
- 56 (7" or 17,5 cm)
- 46 (5,75" or 14,5 cm)
- 38 (4,75" or 12 cm)
- 36 (4,6" or 9,2 cm)
- 16 (also known as "birdies" in theatre as they are "below par")
- (Diameter in inches is found by dividing the PAR size by 8)
- (The number represents the diameter in eighths of an inch)
[edit] Lenses
- Very Narrow Spot
- Narrow Spot
- Medium Flood
- Wide Flood
- Extra Wide Flood
[edit] Intensity
PAR64
- 1000W
- 500W
- 250w (ACL)
PAR56
- 500W
- 300W
- 200W
[edit] Base
This affects what intensity lamps are compatible.
- Mogul End Prong
- Screw Terminal
- 3 Contact Lugs
[edit] Raylite reflector
Raylite reflectors can be added to PAR64 and PAR56 lamp housings to achieve a narrow spot effect. A conventional quartz halogen lamp is used in place of the reflector lamp. A spider or bulb shield may optionally be added, which enhances the parallel nature of the beam and makes it more visible when used with smoke or fog effects.
[edit] Finish
PARs are found commonly with either black finish or polished (silver). PARs can occasionally be found in white.
[edit] Non-sealed PAR alternatives
The Source Four PAR and similar units create light with a similar quality to that of a PAR can, but have lenses separate from the lamp.
[edit] LED
An LED version of the PAR is made by some manufacturers.
LED PAR cans usually are based on an RGB color model.
[edit] PARbars
PARbars are PARs that are permanently affixed to and circuited through an aluminum pipe. Four PARs on a bar are called a 4-bar. 6 PARs are called 6-bars.
[edit] Daylight PARs
HMI PARs produce light with a color temperature equivalent to that of sunlight.
[edit] PAR movers
Intelligent, moving PARs allow for the ability to pan and tilt the instruments through a lighting control console.
[edit] Combination instruments
- The Source Four PARnel combines the attributes of the PAR can and the Fresnel.
- OmniSistem makes a "Profile PAR", combining the attributes of the PAR can and an ellipsoidal reflector spotlight.
[edit] Other attachments
Color
