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Hans Lau

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  1. Local DMX output from a transmitter controlled via Bluetooth has been added to the Moonlite: https://lumenradio.com/lumenradio-adds-new-features-to-moonlite-timotwo-timo-and-the-rdmchip/
  2. Most of GE's Quartzline lamps specify burning position "Horizontal +/- 4 deg". If you are tilting these fixtures you might run afoul of that for some of the lamps in the fixture. That whole family of tubular lamps are notorious for premature failures and it is often exacerbated by reflector designs that trap more heat than the lamps can take.
  3. If you really want to get the exact theoretical numbers you apply 2 formulas from Ohm’s law. The lamps are basically fixed resistors that you put in series. Voltage Squared / Power = Resistance - 28x28 Volts / 600 Watts = 1.3066 Ohms You have 4 of these resistors in series - 4 X 1.3066 Ohms = 5.2266 Ohms Your voltage for calculation purposes would be what you can measure with a meter in your specific setup and not what the combined rating of your series elements is; i.e. not 112V. At 120V supply voltage your setup would result in the following current flow: Voltage / Resistance = Current - 120 Volts / 5.2266 Ohms = 22.95 Amps At a lower voltage than 120V they would draw less current. Note that rated lamp power vs. real lamp power and also utility supply voltages can vary with as much as +/- 5% or more. Bottom line is that you will be over or dangerously near the rating of a 20A breaker.
  4. Hi Stuart Thanks for the clarification. I'll send you a PM in the coming days.
  5. Hi Stuart Just trying to understand and clarify this comment from you: The FilmGear HMI we have in the shop measures 6000-6300K, depending on settings. That's what I initially expected for the Arri as well. Arri must use better bulbs. It's CRI was much, much higher than the FilmGear fixture. HMI CCT and color rendering metrics are primarely a product of the brand of bulb/globe, what kind of usage the the globe has been subjected to, globe running hours and age. System parameters like ballast speed/frequency; optical train such as open face vs. Fresnel, typically have lesser impact on the CCT and color rendering metrics. Filmgear has typically not provided globes/bulbs when the fixtures are sold from us. We normally recommend Osram HMIs (their rated CCT is 6000K) as that is the brand we design and test the fixtures with, but we have no control over what the distributor/dealer/user decides to put in their fixtures. Can I ask you what particular model fixture and brand of globe that you were testing?
  6. According to Osram themselves the first "public" use of the HMI lamp, a 575W, was in 1969 for the first color television broadcast in Germany. The first large scale HMI deployment was for the 1972 Munich olympics.
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