Recent content by John Day

Thank you, Derek, that was very 'illuminating'. :-]

@derekleffew > ... the Fresnel has always played second fiddle to the ellipsoidal reflector spotlight. ...I noticed that the "No. 22" Kliegl Fresnel spotlight (from image at 1stdibs.com in my post above) seemed to have a specialized incandescent lamp, fixed right at the focal point of the...

@ship > ... Trip to ETC. Where I work, Penn State, ... Rubin's thesis is behind a paywall, so I couldn't check it. Perhaps it (or similar documents) would be more freely available to you at Penn State: Rubin, Joel Edward (1960). "The technical development of stage lighting apparatus in the...

The 'Giraffe' spotlight was manufactured by DSL and introduced in this April 1946 issue of Popular Photography as a successor to their 'Fresnel Photospot'...

I'm beginning to have some doubts about the claim at klieglbros.com, that they produced the first Fresnel spotlights in 1929, because none of their old catalogs back up that claim. In fact the first catalog which lists Fresnel spotlights is their 1950 catalog on page 27:The only other image I...

@ship > ... Who was first in brand, and are these the first Fresnels? ...I've being doing some research on this. The first Fresnel lenses (invented by A. Fresnel in 1823) were purposed for improving the illumination of lighthouses. These were big lenses of course, because their light had to be...