Depends on what you want to wash. Both the HE - SS and the Elation have a max. zoom out of 30 degrees, vs. say a Martin 700 wash which has a 65 degree range.
Hee hee! Don't think it would make it into too many "smaller venues" with that instruction of not pointing it at anything closer than 12 feet away! (Love the warning sticker! http://www.highend.com/support/automated_luminaires/showgun/showgunwarning.asp ) Of course it does feed into my evil streak... "You wanted to be stars! Now feel the heat!!"it needs 220v, which in my opinion really sucks because it will never be able to be used in smaller venues here in the states where 120v is standard.
I must respectfully disagree with the statements above. I have editted for clarity, NOT to take JDs comments out of context.
Sorry to hear you disagree, but I stand by my point. When you are talking spots, it's all about point source. If you turn your unit off and open the shutter/douser and look right in the lens, you will see one electrode. That is because only one will end up at the optical center of the reflector. Standardizing lamps and fixtures are one thing, but designing the best spot always requires a tight point source. The closer the electrodes (short arc) the more effective the light source is. In DC xenon spots, the output is primarily on one electrode (thus the different shapes), sadly, ac HMI's produce two equal point sources, one on each electrode. The closer they are, the better, but there can only be one mathematical center to a parabolic, one gate cross point, and one beam convergence.I must respectfully disagree with the statements above.
Agreed, I'm not one to argue with geometry, I always lose; same with gravity--Not just a good idea, it's the Law. I think however you meant ellipsiodal, not parabolic, as ellipsoidal reflectors have "one gate cross point, and one beam convergence." Parabolas have, by definition, one "focal point" but neither of the other two things.
Also, the light from an arc discharge lamp is given off from the arc, same as welding, same as getting a shock, same as lightning. The only effect that the electrodes have on the lamp is that as they start to burn away and the arc gets longer, the color temperature gets warmer. So, yes, a shorter gap gets you closer to a point source, but the light is not given off by the electrodes. If the light were given off by the electrodes we would be back to the black boy radiator model like T/H lamps, and the arc gap wouldn't matter.JD said:The closer the electrodes (short arc) the more effective the light source is. In DC xenon spots, the output is primarily on one electrode (thus the different shapes), sadly, ac HMI's produce two equal point sources, one on each electrode. The closer they are, the better, but there can only be one mathematical center to a parabolic, one gate cross point, and one beam convergence.
You are correct. A parabolic reflector would produce parallel beam output, we are looking for the beam to collapse and thus use that "modified" ellipsoidal reflector! My bad!
Of course what I was referring to was a spot. Your comment brings me back to my original post, in which I stated that "Two different optical trains are used for the different concepts." In most wash fixtures, the front objective lens is the "theatrical" version of a fresnel lens. I say "theatrical" as fresnels do not use a clean step lens, but one that has a pebble-glass finish designed to introduce many refractive errors to produce a more "even" light. It is a far more efficient system than using a frost which contains opaque particles, or a spun fiber diffuser.
Yes, in an HMI lamp, I stand corrected, the metal vapor in the gas arc does produce most of the light. In xenon lamps, the light output is off of the positive electrode, or anode. (see alignment diagram. Picture credit, PTI Photon Technology International) The exception to this would be the common flash tube.