UL24 24" f/3.3 Premium Ultra Light Dobsonian Telescope

UL24 24" f/3.3 Premium Ultra Light Dobsonian Telescope

f/3.3: $10,500

$5,250 USD Deposit (50% of the base system)

  • A quantum leap in optical performance - the UL 24 Truss Dobsonian telescope's huge 24" diameter primary mirror has 9 times the light grasp of popular 8" reflectors and 4 times the light grasp of a 12" telescope.
  • Light, Strong, Compact and Extremely Portable - The Hubble UL24 features a precision-machined all-metal construction. Fully assembled the UL24 weighs about 70 kg. It has 8 rigid truss tubes and extremely strong and portable folding ALT bearing structure. It features a real mirror box for safe mirror protection, and convenient storage and transportation.


UL24 Specs

  • Optical diameter: 609.6mm (f/3.3)
  • Focal length: ~2012mm (f/3.3)
  • Eyepiece height at zenith: 1955mm (~77 in)
  • Optics type: Parabolic
  • Eyepieces: Not included
  • Optical quality: Diffraction limited++ (Strehl 0.95+ for the primary mirror, 1/10 lambda or better in PV for the secondary mirror)
  • Finder scope: Not included
  • Focuser: 2" dual-speed linear bearing Crayford
  • Secondary mirror obstruction: 127 mm
  • Secondary mirror obstruction by diameter: 20.8%
  • Secondary mirror obstruction by area: 4.3%
  • Mirror coatings/over-coatings: 96% Enhanced coating on both of the primary and secondary mirrors
  • Tube material: 6063-T6 Aluminum Alloy tubes with black zinc plated steel knob screws; Aluminum Alloy main structure (OTA and mount) and structure steel mirror cell.
  • Length of optical tube: ~2000mm, 79 in
  • Weight, optical tube: 61 kg
  • Weight, fully assembled: ~70 kg, ~153 lbs
  • Dawes Limit(arcsec): 0.19
  • Rayleigh Limit(arcsec): 0.23
  • Limiting Mag: 16.4
  • Maximum Magnification: 1200
  • Additional, optional accessories: 8x50 Finder, Shroud, Wheelbarrow, Vinyl foam Cushioned Grips
  • Other features: Sling lateral support and deluxe push-pull brass knob collimation screws

Features of the UL24:

Exclusive Sandwich Mirror Technology:

Our sandwich mirror technology has been used to manufacture research-grade optical elements and proven by over a half dozen years of successful applications at research facilities such as NASA, California State Polytechnic University San Luis Obispo, for the US Army, and in amateur telescopes around the world. Hubble sandwich mirror’s open core and close back design not only allows air to circulate through the mirror, but also provide the maximum structure strength to allow a simpler mirror cell design. Our sandwich mirror will reach thermal equilibrium up to 10 times faster than a traditional solid mirror and means the mirror can deliver great views even as the air around the telescope is changing temperature.

Why is thermal equilibrium so critical? The main issue is "mirror seeing," the turbulence seen through the eyepiece of the telescope when the air above the mirror is different from the mirror itself. Since a sandwich mirror cools far more rapidly than a solid mirror of the same thickness, this major source of distortion is eliminated quickly, giving you sharp and stable views. With ever- changing temperatures during observing or imaging, your thick and solid mirror may never reach equilibrium, and never reach its full optical potential. This is one of the major reasons why our lightweight-sandwich mirror has superior optical performance in real world situations, even without an active cooling system. (Active cooling systems, such as fans, introduce their own problems, such as micro vibration, which may seriously degrade the image quality.) Our sandwich mirrors reach equilibrium extremely fast, and without any external disturbing aid.

Enhanced Optical Coatings:

Both the Hubble UL24 primary and secondary mirrors are coated with 96% Enhanced optical coatings to assure it collects as many (while scattering as little) photons as possible to focus it into a bright and contrast-rich image. The optimal 96% enhanced coating has multiple over- coatings of precision controlled dielectric layers to maximize the reflectivity and provide excellent chemical and mechanical protection for the mirror coating.

A Real Mirror Cell In A Real Mirror Box:

The UL24 has an extensively modeled and optimized 18-point flotation system and both sling and 90 degree pivoting lateral supports that provides excellent support for the 24-inch sandwich mirror. The three-point rod-end with easy two front access collimation system is completely independent from the lateral support. It will totally eliminate the often-found potato chip astigmatism introduced when using the simple 3 pivoted bolts collimation system. In a simple pivoted bolts collimation system, the collimation of the primary mirror may cause the sling belt to pull the mirror axially on the mirror edge, bending the mirror to a potato- chip shape, causing annoying astigmatism. It also comes with a real mirror box for easy and safe mirror protection and transportation.

All Metal Construction:

The UL24 mechanical structures have been extensively modeled via 3D CAD and advanced FEA to provide the optimal structure strength and stability. Machined with Computer Numerical Control (CNC) technology and hand fitted to assure proper fit and finish. We use T6063-T3 aluminum alloy truss tubes, structure steel mirror cell and aluminum alloy OTA and mount structure, complete with a deluxe and environmentally friendly black powder coating. As a whole, the structure is such a pleasure to look at, not to mention the enjoyment to look through!

Dual-Speed 2-inch Linear Drive Crayford Focuser:

he Hubble UL24 comes with a precision dual-speed, 2-inch diameter focuser. It's a beautiful piece of precision machining that enhances the viewing experience as well as the overall impression of a premium quality instrument you'll have with this telescope. This focuser is a robust zero-backlash "Crayford-style" design further enhanced with modern "linear bearings" meaning you get a rock-solid, super smooth focusing experience that can handle the weight of even the heaviest of modern eyepieces. Its tension (the pressure on the draw tube) is preset to a very reasonable level, but also adjustable to lock heavy equipment in place if desired. The smaller stainless steel focus control adjusts focus at a rate 10 times finer than the larger focus wheels. This fine adjustment allows for critical focusing during high power visual observing or for imaging applications. The focuser has about 50mm of travel distance.

Why would you select a Hubble UL24?

The Hubble UL24 is a serious telescope for a serious observer, yet is still easily transportable to dark sky locations by one person. This scope not only delivers the premium optical experience you need to explore our universe, but at only about 70 kg in weight (1/3 the weight of classical Dobsonian telescopes) it can easily be folded into a compact package that will fit in almost any car.

The UL24 has a parabolic primary with a full 24-inch diameter of optical surface, a generous 24.4” overall diameter; not a 24-inch blank with a smaller optical surface, which is about 4% more optical surface and light gathering than any other 24” scopes in the market.

The Hubble UL series has been designed to be as light and compact as possible, making the task of transport to your favorite dark-sky site easy. The heaviest component of the UL24 is the primary mirror, which weighs about 30 kg, and the entire telescope is only about 70 kg, which is remarkably light for a 24-inch telescope. In addition, with its fast focal ratio mirror, the Hubble UL24 telescope has an eyepiece location only about 77" from the ground when the UL24 is pointed at zenith.

The Hubble UL24 is the perfect combination of power and portability. With this telescope, you are guaranteed to have a lifetime of exceptional observing experiences, all in a compact 70-kg package!

Happy Customers

"The telescope (Hubble UL24) performed quite well again in Argentina for the MU69 campaign there. Conditions were fairly poor with quite high winds which are typical of the area. The 24" (UL24) handled the winds fairly well with the exception of some extremely strong gusts that hit the telescope directly. The combination of the 24" (UL24) and PCO camera is excellent for occultation work. This setup easily outperforms any other portable occultation setups I know of. It is no worse, or easier, to setup than a 14" Meade or Celestron telescope, and packs in most pickup trucks or SUV's"

-Matthew Nelson, NASA New Horizons Team, Department of Astronomy, University of Virginia

Here are some excellent Sky&Telescopes articles by Kelly Beatty on this exciting mission:

Observers Track New Horizions' Next Target

New Horizons' 2019 Target: A Binary Body?

Jeff Roberson's UL24

Rick Foster with his UL24

Rick Foster with his UL24 at the RASC-TO Dark Sky Observatory in Blue Mountains near Collingwood Ontario.

Jeffrey Hines's UL24

Jeffrey Hines's UL24

Jeffrey Hines's UL24

UL24 at Alfa & Omega Universe Chile

UL24 at Alfa & Omega Universe Chile

UL24 at Alfa & Omega Universe Chile

UL24 at Alfa & Omega Universe Chile

Members of Alfa & Omega Universe Chile

Members of Alfa & Omega Universe Chile

Instructions Manual

Click here for the instructions manual PDF - the Guide and Setup Process.


Click here for the UL24 dimensions when folded.

Order and Shipping Info

There's a 50% deposit for the base system, and the full payment for the optional accessories at the order time, the rest including shipping will be paid before the delivery (about 90 days after the deposit) via a Paypal invoice.

Please note that the 90 days delivery is the estimated production lead time which does not include shipping transit time.

We offer very reasonable worldwide shipping costs for the total system. The Economy shipping is no longer available.

UL24 will be shipped in 4 boxes: the main structure 1 & 2, the truss tubes, the primary mirror.

Country Economy(US$) Regular(US$)
US NA ~1750 (*)
Others NA Contact us

* Shipped via Fedex, the exact cost depends on your specific address.