Photo Gallery

Home > User galleries > Max > Nightscapes and light art
Return to the thumbnail page FILE 2/1130 Return to start See previous file See next file Skip to end
Carbon arc illumination 1 A few years ago a WWII-era Sperry 60‑inch anti‑aircraft carbon arc searchlight was used in an art exhibit in my town. This impressive lighting system draws about 12 kW for an arc current of 150 A, and outputs an 800-million candela beam whose reach extends to 15 km! Here the projector was operated horizontally, with the beam running above and parallel to a straight canal. Shielding plates are placed in front of the projector in order to reduce glare and to limit the amount of light reflected by the water surface. Keywords: Miscellaneous

Carbon arc illumination 1


A few years ago a WWII-era Sperry 60‑inch anti‑aircraft carbon arc searchlight was used in an art exhibit in my town. This impressive lighting system draws about 12 kW for an arc current of 150 A, and outputs an 800-million candela beam whose reach extends to 15 km! Here the projector was operated horizontally, with the beam running above and parallel to a straight canal. Shielding plates are placed in front of the projector in order to reduce glare and to limit the amount of light reflected by the water surface.
2020-09-24_Philips_SOX-E_66W.jpg _DSC2124.jpg _DSC2106.jpg _DSC2110.jpg _DSC2113.jpg
File information
Filename:_DSC2124.jpg
Album name:Max / Nightscapes and light art
Keywords:Miscellaneous
Filesize:1115 KiB
Date added:09 Oct 2026
Dimensions:1800 x 1202 pixels
Displayed:167 times
Model:Z 6_2
Software:Adobe Photoshop 25.7 (Windows)
URL:https://trad-lighting.net/gallery/displayimage.php?pid=1430
Favourites:Add to Favourites

Comment 1 to 4 of 4
Page: 1

Ria   [Sat 10 Oct 2026 at 15:00]
Don't forget to bring your welding goggles Mr. Green
Max   [Mon 12 Oct 2026 at 05:04]
... and some sunblock Wink
AgentHalogen_87   [Mon 12 Oct 2026 at 18:44]
Incredible what gets created when the need arises
Max   [Tue 13 Oct 2026 at 17:31]
And that's not even the biggest searchlight ever made, there are even larger models exceeding 50 kW! The operation of the carbon arc is also a very fascinating subject, a lot of work went into its optimization. The source of light used here is not just an incandescent carbon rod, it's a luminescent anodic crater of a carbon rod cored with metallic additives (usually rare earth salts) which increase the lumen efficacy and the source luminance well beyond the levels possible with the incandescence of carbon alone. And since that luminous crater sits inside the anode rod, light is emitted primarily along the electrode axis (or close to it), which allows the use of a relatively shallow mirror to collect and project light forward. There are some pretty cool stuff there!

Comment 1 to 4 of 4
Page: 1