Zenithstar 61 II

ZWO x William Optics Co-branded Limited Edition

Traditional equatorial mounts often require heavy counterweights, making it challenging to balance the right ascension (RA) and declination (DEC) axes. They are cumbersome to transport and store, causing significant inconvenience for amateur astrophotographers during outdoor sessions. Additionally, some strain wave gear mounts have limited functionality, insufficient payload capacity, and lack stability during use. Addressing these issues, ZWO has developed the ASI Mount series, which eliminates the need for counterweights.

The AM3 weighs only 3.9 kg and supports payloads ranging from 8 kg to 13 kg. While portability is crucial, ZWO prioritizes stability to ensure a reliable user experience. The optimized internal structure incorporates harmonic drive reducers and timing belts, delivering precise control and an impressive 300:1 reduction ratio. The mount is versatile, functioning as either an equatorial or an alt-azimuth mount, and can be controlled via Wi-Fi, Bluetooth, or a handheld controller.

Key Features

Portability and Stability
The optimized internal structure, featuring harmonic drive reducers and timing belts, ensures precise control and stability, achieving a remarkable 300:1 reduction ratio.

Custom Strain Wave Gears
ZWO developed specialized strain wave gears tailored to astrophotography needs, offering extremely low periodic error and high torque. Each mount undergoes factory testing and comes with a unique PE curve to guarantee quality.

Lightweight Design
At just 3.9 kg, the AM3 strikes a balance between portability and stability, prioritizing dependable performance over extreme weight reduction.

8 kg to 13 kg Payload Capacity
Without Counterweights: Supports up to 8 kg.
With Counterweights: Supports up to 13 kg.
(Counterweights should be mounted on a bar no longer than 20 cm.)

Dual Modes: Equatorial and Alt-Azimuth
Equatorial Mode: Ideal for tracking and imaging celestial objects.
Alt-Azimuth Mode: Best suited for visual astronomy.
Easily switch modes using the ASI Mount App or the handheld controller.

Full 0°–90° Altitude Adjustment
Gear 1: Adjust the handle to set angles between 0° and 60°.
Gear 2: Loosen the hex screws to adjust the clamp for angles between 30° and 90°.

Wireless Control
Enjoy features like Tonight’s Target, GOTO, and Live Preview directly from your smartphone via Wi-Fi.

Joystick Hand Controller
Ergonomically designed for comfort and ease of use, the controller integrates with the Wi-Fi network for wireless operation. Firmware updates and installation can be managed effortlessly via a web interface.

Seamless ASIAIR Integration
The AM3 can be controlled via wired or wireless connection with ASIAIR, offering ZWO’s customers an optimized astrophotography experience.

Learn More on ZWO Product Page

ZWO x William Optics Co-branded Limited Edition

Traditional equatorial mounts often require heavy counterweights, making them cumbersome to transport and balance. The AM5N addresses these challenges with a compact, counterweight-free design, offering enhanced portability and stability for amateur astrophotographers. Its optimized internal structure incorporates harmonic drive reducers and timing belts, delivering precise control and a 300:1 reduction ratio. The mount operates in both equatorial and alt-azimuth modes and can be controlled via Wi-Fi, Bluetooth, or a handheld controller.

Key Features

Enhanced Portability and Stability
Weighing only 5.5 kg, the AM5N supports payloads up to 15 kg without counterweights and up to 20 kg with counterweights, maintaining a balance between portability and performance.

Custom Harmonic Drive System
The AM5N features a custom harmonic drive system with a synchronous belt, ensuring high torque, zero backlash, and low periodic error of ±10 arcseconds.

Integrated Cable Management
Internal cable routing through the DEC saddle allows for seamless power and control connections, reducing cable clutter and the risk of snags during operation.

Dual Mount Modes
Switch effortlessly between equatorial and alt-azimuth modes using the ASI Mount App or the included hand controller. A status LED indicates the current mode: red for equatorial and green for alt-azimuth.

Wide Latitude Adjustment
The mount offers a full 0°–90° latitude adjustment range, accommodating various observing locations and setups.

Wireless and Wired Control Options
Control the AM5N via Wi-Fi, Bluetooth, or USB-C connections. The mount is compatible with the ASIAIR system and supports ASCOM and INDI protocols for versatile operation.

Power Failure Protection
An RA axis brake system engages automatically during power failures, safeguarding your equipment from potential damage.

Seamless ASIAIR Integration
The AM5N integrates seamlessly with ZWO's ASIAIR system, providing an optimized astrophotography experience through wired or wireless connections.

Make your ZWO AM3/5 tripod kit load-bearing and stable.

This Tripod Extrapadding Backpack is specifically designed for astro EQ mounts tripod, offering added support and protection for your equipment.

• Thickness: 22mm
• Size: approximately 20 × 20 × 67 cm, with a measurement tolerance of ±3 cm.

Featuring durable Velcro straps for secure attachment, this pouch offers ample storage space to make your wildlife observation experience more convenient.

This 90° 2"mirror-type star diagonal has a Dura-Bright 12mm thick mirror and dielectric mirror coatings for 99% reflectivity which provides higher contrast and resolution during critical planetary, lunar and binary star observations.

Dura-Bright features 100% real carbon fiber side plates that add that touch of class your scope deserves.

The WO 2" Dura-Bright Diagonal was designed with several unique features to provide optimum performance and years of use.

Top-Notch Performance and brightness 

• Dielectric coating allows 99% reflectivity.
• high precision 12mm thick mirror substrate flat for optimal image stability. 
• Polished to 1/12th wave accuracy*.
• Accurate design guarantees constant alignment. No further alignment needed.

Meticulous Craftsmanship

• 2" to 1.25" eyepiece adapter included. 
• Lock screw for eyepiece/adapter. 
• Big, knurled thumbscrews are easy to turn even with gloves on. 
• Threaded for 48mm Filters

Strikingly Beautiful

• Patented, elegant design.
• High-quality machining out of the best aluminum.
• Internal antireflection baffling for highest contrast. 
• Real Carbon Fiber side plates

Superbly Constructed

• Compression rings (both on diagonal and adapter) to prevent barrels from marring.
• Internal safety stop prevents 2" barrels from hitting the mirror. 
• Designed for high-end scope such as FLT-98, FLT-110 , GT/GTF102 and FLT-132.

SCT adapter is optional
SCT ring makes your diagonal work on SC telescopes or our ZS66 series as well! Buy Now

Why W.O. diagonals do not feature an Adjustable alignment system?
Having an adjustable alignment system is an admission that the diagonal can go out of collimation due to poor mechanical construction. Thanks to the patented design of WO diagonals, you will always have a as perfectly as on the first day you got it!

This 90° 1.25"mirror-type star diagonal has a Dura-Bright  thick mirror and dielectric mirror coatings for 99% reflectivity which provides higher contrast and resolution during critical planetary, lunar and binary star observations.

Dura-Bright features 100% real carbon fiber side plates that add that touch of class your scope deserves.

The WO 1.25" Dura-Bright Diagonal was designed with several unique features to provide optimum performance and years of use.

Top-Notch Performance and brightness

• Dielectric coating allows 99% reflectivity.
• high precision 12mm thick mirror substrate flat for optimal image stability.
• Polished to 1/10th wave accuracy*.
• Accurate design guarantees constant alignment. No further alignment needed.

Meticulous Craftsmanship

• Lock screw for eyepiece/adapter.
• Big, knurled thumbscrews are easy to turn even with gloves on.
• Threaded for 1.25" Filters

Strikingly Beautiful

• Patented, elegant design.
• High-quality machining out of the best aluminum.
• Internal antireflection baffling for highest contrast.
• Real Carbon Fiber side plates

Superbly Constructed

• Compression rings (both on diagonal and adapter) to prevent barrels from marring.
• Internal safety stop prevents 1.25" barrels from hitting the mirror.
• Designed for high-end scope

Why W.O. diagonals do not feature an Adjustable alignment system?

Having an adjustable alignment system is an admission that the diagonal can go out of collimation due to poor mechanical construction. Thanks to the patented design of WO diagonals, you will always have a as perfectly as on the first day you got it!  

This 1.25" 90 deg. erecting prism will very happy to be used with that nice premium refractor of yours! Perfect for daytime observations too.

Precision Prism

• Image erecting BAK7 prism with anti-reflection coating.
• High accuracy and high light reflection prism.
• Helical focusing on the top barrel for fine  adjustment.

Superior Craftsmanship

• Internally matte blackened and threaded for no internal stray light reflection.
• Threaded for 1.25" filters.

Beautiful Finish

• Entirely aluminum, black anodized.
• Smooth finish.

William Optics new 45 Deg. EP will work with any 1.25" eyepieces and scopes with 1.25" eyepiece holders. It will turn upside down images right side-up and give correct left-to-right image. This high-quality, low-cost erecting prism will set the standard in erecting prisms!

Large Prism 

• Large, high-quality BAK7 erecting prism with anti-reflection coating allows for good contrast and bright images. 
• Brass compression ring.

Great Price 

• 1.25" eyepiece holder comes with anti-marring brass compression ring. 
• Extremely competitive price/quality ratio.

Innovative Shape 

• Entirely aluminum, black anodized eyepiece holder. 
• Large, chromed thumbscrews.

Advanced Craftsmanship 

• Internally blackened and baffled to prevent internal stray light reflections.

Make your ZWO AM3/5 tripod kit load-bearing and stable.

This Tripod Extrapadding Backpack is specifically designed for astro EQ mounts tripod, offering added support and protection for your equipment.

• Thickness: 22mm
• Size: approximately 20 × 20 × 67 cm, with a measurement tolerance of ±3 cm.

Featuring durable Velcro straps for secure attachment, this pouch offers ample storage space to make your wildlife observation experience more convenient.