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GLASS OF 42"

Below are a series of images showing some of the optical elements and components that will be used to fabricate the 42" Corrected Dall-Kirkham (CDK) telescope. Once complete this telescope will be one of the largest amateur hand made telescopes ever constructed. This site will be updated with additional images showing the progress made in construction and assembly.

42 inch mirror

This image shows the 42 inch primary mirror in the vertical position being prepared for testing. The triangular pattern you see are actually hollow cores in the mirror designed to light weight the mirror while maintaining a solid, stiff front surface.

Glass Grinding

Here you see the 42" primary mirror being ground to shape using two tiled plaster grinding tools and two human tools.

Secondary Mirror

Above shows the secondary mirror assembly that will be suspended over the primary mirror. The secondary is a 14.5" convex spherical mirror that must be supported from the back solely be silicon glue.  Any contact or pressure to the front surface of the mirror could cause flexure that would distort the image quality.

Close-up of secondary mirror

This is a close up of the secondary mirror resting on top of a concave spherical reference mirror. The rainbow lines visible through the back of the secondary mirror indicates how closely the two surface match. The straighter the lines the closer the surfaces match.

 Last Published 4/26/11