The application of ER is many and varied. ER spotlight provides a narrow, beam with a hard edge in a particular direction. It gives a sharp focus of integral metal shutters, metal projection template and the ability to project a metal etched template. This fixture wit its diverse abilities makes it popular among stage lighting designers. ERs have the ability to focus adjustments with the help of moving the lens tube either forward or backwards. This enables a beam range that can be adjusted from harsh and sharp to soft and dim. Still some of the ER’s do not provide for softening the edges of the beam sufficiently for blending and further softening of the edge requires diffusion material. Generally the Ellipsoidal reflector fixtures have one or more numbers with a diameter of 4”,5”,6”,8”,10” and 12”. Wider ER units have two lenses and the thumb rule is that the narrower the beam spread, heavier the fixture used as longer lens barrel with a larger lens (diameter) needed. Usually American manufacturers specify any fixture by putting the lens diameter first and then the focal length, which does not give the information about the degree of beam dispersal of the specific fixture. Now the trend has changed and manufacturers have started specifying the beam spread in degrees. The approximate spread degrees and angles for typical ellipsoidal reflector fixtures are usually about : ) 4.5x9 =50, 6x9 =40, 6x12 =30, 6x16 =25, 6x22 =15, 8x13 =12, 10x23 =9. The new technologically advanced versions of the ER spotlights have beam dispersal of 5 degrees to about 50 degrees with 500 to 2000 watts. Available in fixed length and flexible focal length of zoom capability models, the standard focal length includes 5, 10, 20, 30, 40, 50 degrees. The adjustable focal length units are heavy, low efficiency ratings and expensive compared to the fixed focal length versions. However, a positive aspect of zoom added ERs is that they give optimized performance and can be chosen over fixed focal length spotlights. ER with zooming facility and adjustable focal length has been manufactured since 1970s.They come with the features of spread angle of 12 to 30 degrees and 25 to 50 degrees. However, no single zoom fixture provides wide zooming of 10 to 50 degrees. Looking at options available today, the Ellipsoidal Fixed with a beam spread of 5 to 50 and a 500 to 200 watts has the ability of giving a round beam wit a hard edge, comes with a shutter and gobo slot. The other option is the Ellipsoidal zoom with beam spreads of 15 to 35 zoom and 25 to 50 zoom with a 500 - 2000 watts. It also has a round beam, hard edge with shutters and gobo slot. These fixture kits are inclusive of power cord, four framing shutters, template slot and removable lens tube. The other optional features are: lamp, pipe clamp, lens safety mesh, iris, gobo rotators, template holders, color frames and electrical connectors. You have the option of choosing what suits your need for stage lighting.