2.4 m MDM “Hiltner” Telescope - Forty Years of Excellence

A DFM Engineering Heritage System at MDM Observatory that remains scientifically productive through planned modernization:  Century-class structure, modern control and encoders, built once, upgraded for a lifetime.

Heritage that continues to perform

Why This Telescope Matters

The continued productivity of the 2.4 m Hiltner Telescope is rooted in system-level engineering choices made at its inception. The mount, structure, and drive architecture were designed with high stiffness and favorable dynamic behavior under full optical and instrument load.  This foundation delivered stable tracking and predictable response long before modern control electronics were available.

The Hiltner is a flagship example of DFM’s design philosophy:  Build the structure and optics for a century of service, then modernize electronics on a planned cycle as technology evolves. The result is a large research telescope that remains productive after four decades because it was engineered to accept change, not avoided it.

Learn More: The design philosophy behind long service life.

Modernization Highlights (2019)

TCSGalil stand-alone control decouples telescope operation from host PC dependencies and aging ISA or PCI hardware, providing a clean upgrade path on modern Windows platforms.  TCSGO software provides menu-driven control with continual position display and status reporting, supporting streamlined nightly workflow and remote operation options.

Renishaw 26-bit absolute encoders, on-axis, deliver immediate positional awareness after power events and enable high-precision closed-loop tracking with fast recovery that protects observing time.

These upgrades succeed because the original structural dynamics maintain high system-level stiffness and resonance under full payload, allowing modern control loops to perform without being limited by mechanical behavior.

Learn More:  Modern control that keeps heritage hardware current

Operational Outcomes

• Upgrade without replacement. The control layer modernizes while the mechanical and optical foundation stays in service.
• Faster recovery. On-axis absolute encoders restore positional awareness immediately after interruptions. That returns the system to observing without extended setup steps.
• Lower nightly overhead.  Stand-alone control and a stable software interface reduce dependency chains.
  That simplifies operations and supports remote workflows.
• Performance preserved under real load.  High stiffness and favorable loaded dynamics enables clean servo behavior
  without chasing oscillation.
• Instrument evolution stays practical. Structural capacity and controllable motion support new cameras and spectrographs
  as science changes keeping the facility current.

What Future Customers Can Learn From the 2.4m Hiltner

Longevity through design:  This backlash-free, inertia-matched drive architecture delivered stable motion from the outset. The mechanical and optical foundation remains stable after 40 years because it was engineered for long life at the outset.
Predictable sustainment:  Electronic refresh cycles maintain capability without replacing the telescope.
Operational efficiency:  Absolute encoders reduce setup overhead and support extended exposures, improved pointing accuracy, tracking smoothness, and repeatability.
Lower lifecycle cost:  Upgrading controls at intervals is significantly more economical than replacing large-aperture infrastructure.
Confidence for new instrumentation:  Stiffness, payload capacity, and control precision support new cameras and spectrographs as science evolves.

Learn More: DFM’s performance equation converts cost into mission return: lower jitter, faster settle, higher uptime