A quantum leap in light-gathering power. The UL18's huge 18" sandwich mirror gathers over 5 times more light
than an 8" reflector, with precision all-metal CNC construction and a folding ALT bearing for extreme
portability. Fully assembled weight: just 72 lbs.
f/4.5: $3,595
USD
f/4: $4,095
USD
Deposit (50% of base system)
Sandwich Mirror
Lightweight
All Metal
Dual-Speed Focuser
Aperture
457mm (18")
Focal Ratio
f/4 or f/4.5
Mirror
Sandwich
Weight
72 lbs
Exclusive Sandwich Mirror Technology
The lightweight sandwich mirror design cools dramatically faster than solid mirrors, minimizing thermal
gradients and eliminating a major source of image distortion. Unlike fan-based cooling, this passive
design achieves rapid and stable thermal equilibrium naturally — without introducing vibration.
Why this matters
One of the primary limitations in large-aperture telescopes is "mirror seeing" — turbulence caused by
temperature differences between the mirror and the surrounding air. In changing conditions, a thick
solid mirror may never fully reach equilibrium, preventing it from achieving its full optical
performance. The sandwich mirror design minimizes this effect, allowing the system to reach optimal
performance quickly and consistently, delivering sharper and more stable views without the need for
active cooling.
Enhanced Optical Coatings
96% enhanced reflective coatings on both primary and secondary mirrors with precision-controlled
dielectric layers. Maximum light throughput for bright, contrast-rich images on deep-sky targets.
18-Point Mirror Flotation
Optimized 18-point flotation system in a real mirror box with completely independent Push-Pull
collimation and sling lateral support. Eliminates potato-chip astigmatism found in simpler designs. Safe
mirror protection and easy transportation.
All Metal Construction
CNC-machined 6063-T6 aluminum alloy truss tubes, structural steel mirror cell, and aluminum alloy OTA
and mount structure. 8 rigid truss tubes with folding ALT bearing for extreme portability. Finished with
environmentally friendly black powder coating.
Sharper images with about 40% less coma — no coma corrector needed at all. Smaller central obstruction
(3.1" vs 3.5" for f/4). Easier to achieve perfect collimation. And you save $500.
Advantages of f/4
No ladder needed for most people — the eyepiece stays conveniently close to the ground. Wider field of
view for sweeping panoramic observations.
Both f/4 and f/4.5 provide excellent views. The f/4.5 is perfect for the most demanding observer without a coma
corrector. The f/4 provides a wonderful wider view. With our unique two-section truss tubes for f/4.5, both are
equally portable and strong. Please note that some counter weight will be required for f/4.5 at the bottom (not
provided).
Bill Porte's His-n-Her's UL18s in the Sierra Nevada Mountains
Rick's and Peg's His-n-Her's UL18s at Okie-Tex Star Party
Dan Shiner's UL18 at Cherry Springs Star Party 2019
Add these when ordering, or contact us at info@hubble-optics.com
View all 12 accessories
Carbon Fiber Truss Tubes
$800
Elegant, stronger, and lighter Carbon Fiber Truss Tubes.
Red Dot Finder Scope
$45
Light weight Red Dot Finder with brackets and dovetail. Simple, effective, and easy to adjust. Free
shipping with system.
8x50 Illuminated Finder Scope
$100
Top quality 50mm achromatic finder with dovetail bracket. Scale markings and adjustable red illumination.
+$25 shipping.
Truss Tube Grips
$7 each
0.9m cushioned vinyl foam grips — insulate, cushion vibration, and protect the truss tubes. Free shipping
with system.
Shroud
$120
Top quality Nylon/Lycra blend. Blocks stray light for better contrast. Free shipping with system.
Wheelbarrow Handle
$250
Stainless steel handles with two 6" pneumatic tires and ball bearings. Includes $100 shipping. Order with
system only.
Truss Tube Carry Bag
$60
Deluxe waterproof Nylon bag with draw-string cord. Free shipping with system.
5-Star Artificial Star
$22
Essential collimation tool. Free shipping when ordered with system.
Scope Storage Cover
$120
Polyurethane-coated nylon — light reflecting, water and dust resistant. Full protection in storage and in
the field. Free shipping with system.
Mirror Cover
$45
Strong plastic mirror cover. Free shipping with system.
Light Baffle
$50
Reduces stray light for improved contrast. Free shipping with system.
SkyHub Wireless DSC
$249 + $45 S&H
Wireless Digital Setting Circle with high resolution, low power ball bearing encoders.
Learn more
No fan needed — our sandwich mirror reaches thermal equilibrium without one.
There's a 50% deposit for the base system, and the full payment for the optional accessories at the order
time. The rest including shipping will be paid before the delivery (about 60 days after the deposit) via a
PayPal invoice.
UL18 will be shipped in 4 boxes: the main structure 1 & 2, the truss tubes and the primary mirror.
Country
Regular (US$)
US
870
US (Hawaii)
920
Australia
1017 (EMS)
Austria
720
Belgium
770
Brazil
2350*
Canada
826
Chile
992
Denmark
765
France
790
Germany
780
Israel
860
Italy
710
Japan
510
Korea, South
510
Lithuania
1660
Mexico
905
Netherlands
710
New Zealand
830
Norway
800
Philippines
415
Poland
785
Portugal
905
Romania
880
Russia
1220
Singapore
425
South Africa
1005
Spain
830
Sweden
780
Switzerland
775
Taiwan
480
UK
800
* Shipped via FedEx, the exact cost depends on your specific address.
