The full range is based on a focal ratio of f6.8, fast enough for some superb deep sky photo-visual use and, still have enough focal length for high resolution planetary work both visual and CCD applications.

The tube is constructed from Carbon Fibre sandwich design. Very, very strong to avoid flexing and, zero expansion to ensure the focal plane does not change over long photographic exposures. Being an open tube design and very short, cool down times are remarkably fast.

To assist cool down of the telescope, each model is fitted with three fans, all positioned behind the primary mirror.

Exact focusing across the ODK range is achieved with a Starlight Instruments FTF301B-A Feather Touch 3 Inch dual speed focuser included as standard - pictured below right.
Good images need good optics, all fitted in reliable, stable and precise engineering.

Customers with heavier than normal (4kg+) CCD equipment can add features to the ODK tube to enhance stability.
ODK Light Path Diagram
To produce the photo-visual wide, flat field of the ODK range, we have designed and fitted integrally, a corrector lens system. which ensure both colour correction, coma and spherical aberration are optimised to achieve almost a perfect photographic and visual field. Adequate back focus allows all modern CCD cameras to be used with auxiliary equipment. Multi layer anti reflection coatings are applied to all lens surfaces to maintain brighter images.

CNC machined mono construction secondary spider and trim ensures stability in collimation. Our unique collimation adjustment system enables perfect collimation of the secondary mirror to be achieved, quickly and reliably.