I knew a few projectionists that worked with carbon arc. They all used a welding mask
http://www.hometheaterdiscussion.com/forums/showpost.php?p=57980&postcount=9
This is a short story I originally posted at HTD when I was researching the DIY Anamorphic lens...which has been a huge success by the way...
Mark
Somewhat related...
The same basic principal was used in spotlights for many years. Heck, a lot of arenas and large concert halls still use carbon arc spots. We have 6 Strand Troopers in my hometown and they are big, heavy, and dirty behemoths. Running a carbon arc light is an art form in itself, and the number of people that can run one well is diminishing quickly.
Btw, a small window with #10 welding glass is on the side of the lamphouse to allow viewing of the arc without damaging the eyes.
The same basic principal was used in spotlights for many years. Heck, a lot of arenas and large concert halls still use carbon arc spots. We have 6 Strand Troopers in my hometown and they are big, heavy, and dirty behemoths. Running a carbon arc light is an art form in itself, and the number of people that can run one well is diminishing quickly.
Btw, a small window with #10 welding glass is on the side of the lamphouse to allow viewing of the arc without damaging the eyes.
Mark,
Hard to believe that I just found your link.
This is one forum I don't monitor regularly. I'm going to have to put this on the list.
Anyway, a couple corrections to what you wrote.
Conventional films don't have any squeeze. The are projected what we call "flat".
The old original movies (before the '50s or so) were 1.33:1.
Then came "wide screen" or around 1.66 to 1.85:1
These use conventional lenses.
Scope is 2.35:1 aspect ratio with a 2/1 stretch.
Also, the primary determinant of color from a carbon arc isn't so much the arc gap but the distance from the reflector.
I'd have to check my reference books, to see which direction (too far or too close) from the reflector produced which color. Let me know, and I'll find it for you. The correct distance obviously produced perfect daylight white.
Hard to believe that I just found your link.
This is one forum I don't monitor regularly. I'm going to have to put this on the list.
Anyway, a couple corrections to what you wrote.
Conventional films don't have any squeeze. The are projected what we call "flat".
The old original movies (before the '50s or so) were 1.33:1.
Then came "wide screen" or around 1.66 to 1.85:1
These use conventional lenses.
Scope is 2.35:1 aspect ratio with a 2/1 stretch.
Also, the primary determinant of color from a carbon arc isn't so much the arc gap but the distance from the reflector.
I'd have to check my reference books, to see which direction (too far or too close) from the reflector produced which color. Let me know, and I'll find it for you. The correct distance obviously produced perfect daylight white.
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