Sat Jan 13, 2018 9:13 am
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
"Novelty is always welcome, but talking pictures are just a fad." -- Irving Thalberg
"Who the hell wants to hear actors talk ?" -- Harry Warner