Keck Telescope IR Secondary,.5 Meter Dia.
The secondary mirror, positioned some 17.5 meters from the primary, was fabricated of beryllium by Brush Wellman, and machined by Axsys (Speed Ring), and optically figured on the LODTM at Lawrence Livermore Labs.

In 1997 Epner Technology, after rehearsing on a aluminum "pathfinder" blank, coated the actual beryllium mirror with 0.5 mircrons Laser Gold.

After some three years of deep space IR research in the Keck Observatory, ETI was asked to coat two more mirrors for the Keck II Observatory; an f25 and f40 aperture.

While exhibiting at the Kona Hawaii SPIE meeting of the worlds astronomers in 1998, David Epner was offered a VIP tour of the Keck I Observatory. He was dismayed to see "his" mirror covered with condensate residue. He was told by the technicians touching the gold surface was forbidden. Epner replied, "The whole purpose of using Laser Gold was because it could be cleaned". Only after offering to re-coat the mirror at no charge if damaged by cleaning did the young technician agree to wipe down the mirror with alcohol, acetone or just detergent and DI water.