Tweet Carbon arc projectors

Anyone ever see a film projected from a carbon arc projector?

What was it like? How did they handle the rod changes.

Yes, that's what was used when I started in the business. What did it look like? A movie on the screen. As long as the carbons were adjusted properly, a nice white light. Changing the carbon rods was done between reels, similar to putting the next reel of film on the idle projector.
I know there will be people commenting on this, advocating carbon arc vs. xenon. I won't argue for one or the other, it's just the way things were done at the time.

Thanks!

I was just curious if the light was a different hue or look than bulbs or if there was a flicker in the arc light. It sounds like a disaster waiting to happen. Arc light and nitrate film!

There were nitrate fires in cinemas.
In the UK there had to be a projectionist on duty by the running projector all the time.There were metal gates by the port which would be brought down if required.
In the fifties I have clear memories of the picture fading to brown because the projectionist failing to attend to the arcs.

These were the usual means of projection when I was young.

In properly run cinemas the projectionist managed the carbons and the gap very carefully to ensure even illumination through all shows. Some of the third rate places ran down the carbons below acceptable levels to cut costs, which led to some flickering and low light levels.

I still regard the Xenon lamp as a pretty recent innovation, which may explain why I follow this site.

A carbon arc lamphouse produces a perfectly fine white light --- if the carbons are aligned properly and gapped correctly, and if the lamphouse mirror is clean and focused properly, and if the rectifier (which converts AC to DC for the lamphouse power source) is adjusted correctly. That's what experienced, good projectionists did!

Xenon bulbs also produce great illumination, and probably more light (and heat) than a carbon arc setup. Of course, they are also a lot more expensive to run! But I have seen more than a few Xenon bulbs explode inside the lamphouse, likely as the result of fingerprints on the bulb glass, which can create hotspots because oil from the fingertips on the glass absorbs heat. (The bulbs are supposed to be installed while wearing gloves.) In addition to being very dangerous, that also creates one heck of a mess to clean up. SETH

Having run both extensively, the difference between the two is negligible (maybe +1 for Xenon because the arc is generally more stable). But running carbon is fun, to say the least.

[silentfilm]

If you can catch Peter Flynn's documentary The Dying of the Light (2015), you can see a lot of carbon arcs in action. You can also briefly see Jack Theakston...

Whenever I had to visit the bio box at the cinema at which I worked (usually lugging cans of films up all the stairs!), I was always fascinated when I arrived there early some mornings before the daily performances and found the projectionists fiddling around with the projectors, focusing the carbon-arc rods. They used to have a special film they put through which aided in this focusing.

I somehow think that all the care that used to go into the projection of films by those who cared about what they were doing, is now a lost art - at least judging from my last visits to the cinema which I must admit are a few years ago now.

We also had Brenograph projectors which did wondrous effects - I wonder how many people are around now who would know what I am talking about?

[silentfilm]

Whenever I had to visit the bio box at the cinema at which I worked (usually lugging cans of films up all the stairs!), I was always fascinated when I arrived there early some mornings before the daily performances and found the projectionists fiddling around with the projectors, focusing the carbon-arc rods. They used to have a special film they put through which aided in this focusing.

I somehow think that all the care that used to go into the projection of films by those who cared about what they were doing, is now a lost art - at least judging from my last visits to the cinema which I must admit are a few years ago now.

We also had Brenograph projectors which did wondrous effects - I wonder how many people are around now who would know what I am talking about?

I must admit I cheated a bit and looked it up.

This brings to mind a starfield/nebula projector like this. Maybe it could be customized to slow it down some to match the Brenograph, but basically these operate on the principle of rotating discs too.

https://www.youtube.com/watch?v=JOelqeNkOsk



This one may or may not be sufficient in a large theater, it is designed for a 50 ft. x50 ft. coverage space. Actual results would probably depend on the color of the ceiling/light absorption, and how large the area to be covered is.

Thanks for all the great replies. Fascinating stuff! I ordered the Light DVD. Glad this stuff was archived.