The ODK20Tr Truss Optimised Dall-Kirkham Telescope is an elite, observatory-grade 500mm (20-inch) optical tube assembly (OTA) designed for professional research, institutional observatories, and advanced deep-sky astrophotography. Hand-crafted and optically figured at our specialized facility in the UK, the ODK20Tr delivers massive light-gathering power alongside uncompromised mechanical and thermal stability.

Our optical designs carry a prestigious pedigree, having been supplied to world-renowned research bodies including the ESO (European Southern Observatory) and ENO (European Northern Observatory). The ODK20Tr is directly evolved from our technical frameworks that have assisted in the control and calibration of the enormous main instruments at the Paranal Observatory (Chile) and the Canary Islands. When you invest in the ODK20Tr, you are deploying professional, flight-proven optical excellence.

While other telescopes on the market utilize simplified 2-lens correctors to save costs, we don’t skimp on optical perfection. Extensive computer designs prove that a premium, integrated 3-lens multi-coated corrector system is vital to ensuring a perfectly flat, wide field. This extra lens element creates a massive corrected imaging circle spanning well over 52mm, ensuring pinpoint star profiles and spectacular contrast right to the very edge of modern large-format sensors.

Supporting a 500mm primary mirror requires structural perfection. The ODK20Tr features an advanced open carbon fibre sandwich truss framework. This lightweight, ultra-rigid geometry eliminates structural flexure and exhibits a near-zero thermal expansion coefficient. As ambient dome temperatures drop throughout the night, the telescope securely locks its focal position, eliminating the need for repetitive and disruptive automated refocusing routines.

The primary mirror is cradled inside a custom honeycomb CNC-machined aluminium flotation cell to ensure distortion-free wavefront performance. To counteract boundary layer air currents and accelerate thermal equilibrium, the cell integrates 3 controllable cooling fans. For rock-solid imaging, every ODK20Tr is equipped with our specialized 3” CERES focuser, featuring a 10:1 reduction Crayford mechanism to support heavy imaging trains with zero flexure.