![[Prototype] Cat 61 WIFD](http://williamoptics.com/cdn/shop/files/Redcat-61-WIFD-prototype-2.jpg?v=1786606271&width=2400)
![[Prototype] Cat 61 WIFD](http://williamoptics.com/cdn/shop/files/Redcat-61-WIFD-prototype-1.jpg?v=1786606272&width=2400)
[Prototype] Cat 61 WIFD
This Cat 61 WIFD Prototype comes directly from our product development process and retains the same optical design and imaging performance as the standard production model.
During development, this prototype resulted in a few differences from the final production configuration:
- Soft carry case not included
- Mounting plate shows significant cosmetic scratches from development and testing. These marks do not affect normal mounting or operation.
- Prototype extendable dew shield — unlike the final production Cat 61 WIFD, this unit was built as part of an early trial for a telescoping dew shield design. The dew shield is longer than the production version and can be extended further, giving this prototype a distinctive feature not found on the standard model.
- Includes a one-year warranty with an official William Optics warranty card.
Optical performance is identical to the standard production Cat 61 WIFD. The prototype designation refers to the mechanical configuration and cosmetic condition described above, with no compromise in optical quality or imaging performance.
Accessory Add-ons
Guider
UniGuide 32mm f/3.75
- Lens Type
- Doublet Lens
- Focal Length
- 120 mm
- Diameter
- 32 mm
- Focal Ratio
- f/3.75
- Tube Length
- 147 mm
- Total Weight
- 0.23 kg / 0.51 lbs
Camera
ZWO ASI 120MM Mini
- Sensor
- AR0130CS CMOS ( color )
- Resolution
- 1280 x 960
- Pixel Size
- 3.75μm
- Sensor Size
- 1/3″ ( 4.8 mm x 3.6 mm )
- Max Frame Rate
- 35 fps
- Read Noise
- 4.0e
- Quantum Efficiency
- 80%
- Exposure Range
- 64µs-1000s
- ADC
- 12 bit
- Flange Distance
- 8.5mm
- Camera Thread
- M28.5
- Adapter Included
- 1.25" Extender ( 22mm ) CS → M28.5 Adapter ( 4mm )
- Interface
- ST4 USB 2.0 Type-C
- Cable Included
- ST4 ( 2m ) USB 2.0 Type A↔C ( 0.5 & 2m )
- Camera Weight
- 60 g / 2.1 oz
Camera Adapter
Elite Drawer OAG Kit
- Light-In Side
- M54, M48, M68
- Light-Out Side
- Main: M54, M48 ( M42 optional ) / Guide: M42, 1.25" push-in
- Optical Length
- 37.5 mm
- Weight
- 336 g / 11.85 oz
M42 Adapter for Elite Drawer OAG Kit
- Light-In Side
- Trapezoid lock structure for OAG
- Light-Out Side
- M42 × 0.75
M48 T-mount for Nikon Z Mirrorless
- Light-In Side
- M48 (female)
- Light-Out Side
- Nikon Z Mirrorless Camera Mount
- Optical Length
- 38.4 mm
M48 T-mount for Nikon F
- Light-In Side
- M48 (female)
- Light-Out Side
- Nikon F Camera Mount
- Optical Length
- 8.2 mm
M48 T-mount for Canon EOS R Mirrorless
- Light-In Side
- M48 (female)
- Light-Out Side
- Canon EOS R Camera Mount
- Optical Length
- 34.4 mm
M48 T-mount for Canon EOS
- Light-In Side
- M48 (female)
- Light-Out Side
- Canon EOS Camera Mount
- Optical Length
- 10.6 mm
T-mount for Sony E
- Light-In Side
- M48 (female)
- Light-Out Side
- Sony E Camera Mount
- Optical Length
- 36.7 mm
M48 T-mount for Pentax K
- Light-In Side
- M48 (female)
- Light-Out Side
- Pentax K Camera Mount
- Optical Length
- 9.3 mm
M48 T-mount for Fuji FX
- Light-In Side
- M48 (female)
- Light-Out Side
- Fuji FX Camera Mount
- Optical Length
- 37 mm
M48 T-mount for Olympus Micro 4/3
- Light-In Side
- M48 (female)
- Light-Out Side
- Olympus Micro 4/3 Camera Mount
- Optical Length
- 35.6 mm
M48 → M42 Adapter
- Light-In Side
- M48 (female)
- Light-Out Side
- M42 (male)
- Optical Length
- 5.3 mm
EQ Mount
ZWO AM5N RedCat Limited Edition
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.
Counterweight Shaft
- Material
- Aluminum alloy
- Diameter
- 20 mm
- Shaft Length
- 383 mm
Mounting
Pair of Riser Blocks
- Length
- 55 mm
- Width
- 20 mm
- Height
- 15 mm
- Telescope
- Cat-61 P-68
- Weight
- 76 g / 167.55 lbs
Tripod
Pier Mount 90
- Adapter
- 3/8" Thread ( for ZWO AM3/AM5 )
More EQ Mount types are optional - Weight
- approx. 7 kg
- Loading Capacity
- 90 kg / 198 lbs
- Height
- Stance: 89.3 cm Closed: 79.3 cm Foot Adjustable Height Range: 15 mm
- Material
- Aluminum Alloy
- Pillar Diameter
- 100 mm / 4"
![[Bundle] ZWO Mount Upgrade Kit](http://williamoptics.com/cdn/shop/files/ZWOMountUpgradeKit.jpg?v=1724140371&width=2400)
[Bundle] ZWO Mount Upgrade Kit
Make your ZWO AM3/5 tripod kit load-bearing and stable.
Tripod Extrapadding Backpack
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.
Camouflage Tripod Pouch
Featuring durable Velcro straps for secure attachment, this pouch offers ample storage space to make your wildlife observation experience more convenient.
Diagonal
Mounting
Pair of Riser Blocks
- Length
- 55 mm
- Width
- 20 mm
- Height
- 15 mm
- Telescope
- Cat-61 P-68
- Weight
- 76 g / 167.55 lbs
Tripod
Pier Mount 90
- Adapter
- 3/8" Thread ( for ZWO AM3/AM5 )
More EQ Mount types are optional - Weight
- approx. 7 kg
- Loading Capacity
- 90 kg / 198 lbs
- Height
- Stance: 89.3 cm Closed: 79.3 cm Foot Adjustable Height Range: 15 mm
- Material
- Aluminum Alloy
- Pillar Diameter
- 100 mm / 4"
[Bundle] ZWO Mount Upgrade Kit
Make your ZWO AM3/5 tripod kit load-bearing and stable.
Tripod Extrapadding Backpack
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.
Camouflage Tripod Pouch
Featuring durable Velcro straps for secure attachment, this pouch offers ample storage space to make your wildlife observation experience more convenient.
- Lens Type
- 4-Element Petzval
- Focal Length
- 300 mm
- Diameter
- 61 mm
- Focal Ratio
- f/4.9
- Image Circle
- 46 mm
- Focuser
- WIFD R&P Focuser Compatible with EAF
- Focuser Travel
- 0-42 mm (Ruler to 50mm)
- Adapter Included
- Tilt Adjuster M60 → M54 Rotator M54 → M48 Adapter
- Optional Flattener
- No Flattener Required
- T-Mount Support
- Canon EF, RF Nikon F, Z Sony E Pentax K MFT (M4/3) FUJI X
- Camera Format
- Full Frame APS-C M4/3
- Dovetail Type
- Vixen ↔︎ Arca-Swiss
- Tube Length
- 383 mm - 450 mm
This Cat 61 WIFD Prototype comes directly from our product development process and retains the same optical design and imaging performance as the standard production model.
During development, this prototype resulted in a few differences from the final production configuration:
- Soft carry case not included
- Mounting plate shows significant cosmetic scratches from development and testing. These marks do not affect normal mounting or operation.
- Prototype extendable dew shield — unlike the final production Cat 61 WIFD, this unit was built as part of an early trial for a telescoping dew shield design. The dew shield is longer than the production version and can be extended further, giving this prototype a distinctive feature not found on the standard model.
- Includes a one-year warranty with an official William Optics warranty card.
Optical performance is identical to the standard production Cat 61 WIFD. The prototype designation refers to the mechanical configuration and cosmetic condition described above, with no compromise in optical quality or imaging performance.
Expert Review
William Optics SpaceCat 61mm Review
William Optics RedCat 61