Larry Parker from Mole Richardson demos a Carbon Arc light with a guest appearance by Rodrigo Prieto, ASC

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“‘Home Alone’ is one of the last films shot with an old carbon-arc lighting system that was popular back in the 1940s through 1960s for Technicolor films,” the director explained. “That means you have to put a carbon piece of charcoal into each lamp and it creates a warmer and richer light to shoot.”

Columbus said the movie’s cinematographer, Julia Macat, insisted on doing the lighting this way for the entire film. The result is that “Home Alone” has a warm and rich look, perfect for a holiday movie — and when you’re trying to imitate the look and feel of an old movie.

68 volts volts 135 amps
apparently it’s more like 9180W.
9kw use 18kw of light
they are 5,000K temperature, no need for filters to color correct,

Its use DC. He said his rectifier is old so it makes this noise. I think transformer before rectifier makes this noise.

Actually its the transformer humming.. Its steps DOWN the voltage to 65v and as a good transformer maintains wattage if you put 220v at 60 amps lets say. That would be 13,200 Watts of power, assuming 100% transformer efficiency the output wattage would be the same, but at a reduced voltage, so the current increases to 203amps (220v x 60a input = 13,200 watts. 13,200 Watts/65v on output = 203 amps) MORE than enough to draw a powerful arc on the carbon rods. Since the output of a transformer is AC and the light needs DC, the AC needs to be converted to DC by way of rectifiers.
To maintain the arc as thw rids burn away, there is a motor that pushes the rod closer to make up for the burning off of the rod. Thats that knob at the top that is rotating on its own. There is a motor speed control knob that keeps the motor at a certain speed which the operator must adjust to maintain that arc

“This is being fed with AC which is three phase… 68 volts 135 amps.”

An overview of three main sources of light in the theater and why two of them really don’t like being put on a normal dimmer.

Cree’s XLamp XHP50.2 LED delivers up to 7% more lumens and 10% higher LPW (lumens per watt) than the first-generation XHP50 LED in the same 5×5-mm package. The XHP50.2 provides more than 2500 lumens from its 6-mm light-emitting surface, helping to reduce the size and cost of new designs in applications ranging from spot to street lighting.

LEDs are the most efficient way to turn an electric current into illumination. When a current flows through a diode in the forward direction, it consists of surplus electrons moving in one direction in the lattice and “holes” (voids in the lattice) moving in the other. Occasionally, electrons can recombine with holes. When they do, the process releases energy in the form of photons.

This is true of all semiconductor junctions, but LEDs use materials that maximize the effect. The color of the light emitted (corresponding to the energy of the photon) is determined by the semiconductor materials that form the diode junction.

The latest high-brightness (HB) white LEDs are made possible by the discovery of semiconductor materials that produce blue or ultraviolet photons. In addition to the diode, an HB package contains “yellow” phosphors on the inside of its lens. Some “blue” photons escape, but others excite the phosphors, which then give off “yellow” photons. The result can be tuned in manufacturing to produce “white” light.

A great deal of LED engineering relates to controlling the quality of this light.

Research using a re-radiating nanostructure around a planar incandescent surface may give the classic but inefficient light source a second chance.

It’s natural to feel at least a little bit of sadness, and even pity, for the venerable incandescent bulb. It was heralded as a technological miracle, brought safe, effective lighting to the world, and it completely transformed society. Yet, it is now derided as an inefficient energy hog and thus a bad thing.

A combination of energy costs and regulatory mandates have given the blub little room to maneuver, and it is being superseded in most consumer and many commercial applications by CFLs and, to an increasing extent, by LEDs (although incandescents are still the preferred or only option for many specialized applications). Phasing out incandescents makes logical sense, since they have efficacy of only about 2%-3%, compared to several times that for CFLs (7% to 15%) and LEDs (5% to 20%).

That’s why I found a recent update from MIT of great interest. A research team has done work, including a demonstrated proof of concept, on a radical approach for increasing the performance of the incandescent bulb

Thus far, they have achieved efficacy of about 6.6%, which is 2x to 3× that of a regular incandescent bulb. Note that the “filament” they use is not a conventional tungsten wire; instead, it is thin, planar sheet of tungsten which has been laser cut to fit.

Will this design bring back the incandescent bulb, with its primitive glow and pleasing color temperature? I certainly don’t know.

Further, we also know that developments in one area (even dead-end ones) often become the basis of innovation in others.

The light intensity curves for LEDs, regardless of whether they are collimated with a lens or reflectors, follow a bell shaped curve (often referred to as a “Lambertian“ curve). The 50% intensity point for an LED with no optic (bare LED) is virtually always at approximately 120 degrees (60 degrees in each direction).

The 50% point (known as the “beam angle” or “viewing angle”) is a lesser number of degrees depending on the collimating specification used. The beam angle is the total angle in both plus and minus directions.

What is not commonly known by those not experienced in the physics of LED light emission and optics is that the Lambertian LED light intensity curves can be very misleading in terms of how much light is actually arriving at the receiving end.

Our new house is inching towards 100% LEDness, from LED “bulbs” in standard light fixtures, to custom LED lighting, to flexible LED light strips. It’s the latter I’m having some problems with.

After some preliminary research, I decided that the only affordable sources for LED strips would be from among the numerous Shenzhen & Hong Kong mega-retailer Websites. There, you’ll find standard 5m LED strips in the $4-$20 range, instead of the $50-$100 range typical of other sources.

After some preliminary research, I decided that the only affordable sources for LED strips would be from among the numerous Shenzhen & Hong Kong mega-retailer Websites. There, you’ll find standard 5m LED strips in the $4-$20 range, instead of the $50-$100 range typical of other sources.

With the LEDs themselves taken care of, I turned to power sources. In the basement, I’ll probably use some centralized high current 12V power supplies..

While I’m willing to accept some creative LED specs, I do expect a 5A adapter to be a 5A adapter. Silly me. They turned out to be more like 2A, and to add insult to injury, the output cables appeared to be vastly undersized

With the crazy extremes of light flux density that are possible these days, we’re putting quotation marks around “world’s brightest”, but it’s abundantly clear that this flashlight build is very much too bright. No, really. Why would you want a flashlight so bright that you have to wear sunglasses to look at anything that’s within a twenty foot radius?

Because you can. [Mads Nielsen] combined 18, one hundred Watt LED units with some giant machined heatsinks, fans to cool those heatsinks, lenses, and other hardware to make a device that turns electrons into photons at an alarming rate. Each chip-on-board LED package requires 32 Volts

World’s Brightest LED Flashlight (1800W / 162.000 Lumen)
http://ec-projects.com/worlds-brightest-led-flashlight-1800w-162000-lumen

American Silicon Valley headquartered LED Engin has introduced led component, which was the first in the world to produce seven different colors. It can be implemented in the entire color spectrum repetitive stage light applications.

LZ7 circuit 7 is independently controllable LEDs 7 x 7 millimeters platform. Chassis development has been a core material and design of thermal management.

Source: http://etn.fi/index.php?option=com_content&view=article&id=4201:ledivalo-tuottaa-koko-valospektrin&catid=13&Itemid=101

LuxiGen™ Multi-Color Emitter Series
LZ7 Flat Lens Emitter
RGBW-PC Amber-Cyan-Violet
LZ7-04MU00
http://www.ledengin.com/files/products/LZ7/LZ7-04MU00.pdf

7-color surface mount ceramic LED package with integrated flat glass lens
Red, Green, Blue, Cool White, PC Amber, Cyan and Violet enables richer and wider color combination for more sophisticated color mixing
Compact 3.8mm Light Emitting Surface (LES) and low profile package maximize coupling efficiency into secondary optics
20W max power dissipation in a small 7.0mm x 7.0mm emitter foot