Hubble UL32 – 32" Lightweight Reflector Telescope
The Hubble UL32sg is a flagship 32-inch Dobsonian telescope designed for serious deep-sky observers, research-grade visual work, and advanced EAA applications. With a massive 32-inch primary mirror, the UL32sg delivers 16 times the light grasp of an 8-inch telescope and four times that of a 16-inch, revealing galaxies, nebulae, and fine structure at a level few instruments on Earth can match.
Despite its extraordinary aperture, the UL32sg is engineered to remain as compact and transportable as possible for its class. Fully assembled, the telescope weighs around 150 kg and features a modular, all-metal construction with sectional truss tubes and a folding altitude bearing structure. A real mirror box provides safe protection for the primary mirror during transport and storage.
Light, Strong, Compact and Still Portable
The UL32sg is built using precision-machined aluminium alloy components, extensively modelled with CAD and FEA to optimise structural rigidity while minimising weight. Eight rigid sectional truss tubes ensure excellent stiffness and collimation stability, even at extreme elevations.
While the UL32sg is not a casual backyard instrument, it remains one of the most compact and practical 32-inch class telescopes available, capable of being transported and assembled by a small team for dark-sky expeditions, observatories, and research installations.
Revolutionary Smart Go-To System
The UL32sg is supplied exclusively in a Smart Go-To configuration, built around the state-of-the-art OnStep control system. This advanced platform combines fully motorised Go-To, high-resolution encoders, and a revolutionary plate-solving smart finder for unmatched pointing accuracy.
Using the system is simple: select a target via the smart hand controller or third-party software such as SkySafari or Stellarium, then with a single button press the telescope captures an image, plate-solves its position, and automatically refines its pointing until the target is perfectly centred.
The system supports automated star alignment, automated “Star Shows” such as Messier Marathons, intelligent routing to reduce slewing time by 30–50%, and full EAA live stacking for electronically assisted observing.
Connectivity includes built-in WiFi and Bluetooth, INDI and ASCOM drivers, real-time clock, spiral search, park/unpark, and full sidereal, lunar, and solar tracking rates. Control is available via smart hand controller, desktop software, or mobile apps on Windows, macOS, Linux, iOS, and Android.
Exclusive Sandwich Mirror Technology
The UL32sg uses a lightweight sandwich primary mirror designed to reach thermal equilibrium far faster than traditional solid mirrors. Rapid cooling dramatically reduces mirror seeing and internal turbulence, allowing the telescope to achieve its full optical potential much sooner in real-world conditions.
Unlike thick solid mirrors that may never stabilise during changing temperatures, the sandwich design delivers sharp, stable images without the need for active cooling systems, avoiding vibration and mechanical complexity.
Enhanced Optical Coatings
Both primary and secondary mirrors receive 96% enhanced dielectric coatings with multiple precision-controlled layers. These coatings maximise reflectivity, reduce scatter, and provide excellent chemical and mechanical durability, delivering bright, high-contrast images even at extreme magnifications.
Real Mirror Cell in a Real Mirror Box
The UL32sg features a fully engineered 27-point flotation mirror cell with sling and 90-degree pivoting lateral supports. This system prevents mirror deformation and eliminates astigmatism commonly caused by simpler collimation designs.
The independent three-point rod-end collimation system allows precise adjustment without stressing the mirror edge, maintaining optical integrity under all observing orientations.
Dual-Speed 2" Linear Bearing Crayford Focuser
The UL32sg is fitted with a precision 2-inch dual-speed linear bearing Crayford focuser, capable of handling heavy modern eyepieces and imaging equipment. The fine focus control provides ten times finer adjustment for critical focusing at high power or during EAA use, with approximately 50 mm of travel.
Specifications (UL16)
| Optical design | Reflector |
|---|---|
| Optical diameter | 32" (812.8 mm) |
| Focal length | ~2683 mm |
| Focal ratio | f/3.3 |
| Eyepiece height at zenith | ~2570 mm |
| Optics type | Parabolic |
| Control system | State-of-the-art OnStep Smart Go-To |
| Eyepieces | Not included |
| Optical quality | Diffraction limited++ (Strehl 0.95+ for primary 1/10 λ PV for secondary) |
| Finder scope | Not included |
| Focuser | 2" dual-speed linear bearing Crayford (50.8 mm) |
| Secondary mirror | 180 mm |
| Secondary mirror obstruction by diameter | 22.1% |
| Secondary mirror obstruction by area | 4.9% |
| Mirror coatings / over-coatings | 96% Enhanced coating on primary and secondary mirrors |
| Tube material | 6063-T6 Aluminium Alloy tubes with black zinc-plated steel knob screws aluminium alloy main structure (OTA and mount) and steel mirror cell |
| Length of optical tube | ~2600 mm |
| Weight, optical tube | ~120 kg |
| Weight, fully assembled | ~150 kg |
| Connectivity | Built-in WiFi and Bluetooth |
| Power supply | Control: 12 VDC 2A Motors: 24 VDC 5A |
| Dawes Limit | 0.14″ |
| Rayleigh Limit | 0.17″ |
| Limiting Magnitude | 17.3 |
| Maximum Magnification | 1600× |
| Additional / optional accessories | 8×50 Finder Tube Shroud Wheelbarrow handles Vinyl foam cushioned grips |
| Other features | 27-point flotation mirror cell sling lateral support deluxe push-pull brass knob collimation screws |
