William Optics Ultra-Cat 108 f/4.8 WIFD Petzval Refractor Telescope
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Top-of-the-line Refractor for Astrophotography
Introducing the William Optics Ultra-Cat 108! This 5-element Petzval refractor features top-of-the-line components which enable sharp stars across a huge 60mm image circle. With a fast f/4.8 focal ratio and premium glass elements, this telescope is designed for the most demanding imagers.
60mm Image Circle: Medium Format Ready
The massive 60mm image circle means this telescope can support cameras with sensors as large as medium format. Full frame sensors are a breeze for the Ultra-Cat 108. William Optics have provided these impressive spot diagrams to prove its capabilities out to a 30mm radius, meaning it can handle the 55mm diagonal of medium format sensors with ease:
Premium Glass Elements
To produce a huge image circle with sharp stars like the Ultra-Cat 108 has, a telescope needs top-notch glass. The Ultra-Cat 108 features just that with a total of 5 impressive elements, including an ultra-premium Lanthanum glass element rarely found in this price range:
- Super ED Glass x2
- ED Glass x1
- Lanthanum Glass x1
- X-Element x1
Fast F/4.8 Focal Ratio
With a focal length of 518mm and an aperture of 108mm, the Ultra-Cat has a fast f/4.8 focal ratio which is perfect for many applications. When paired with a full frame or especially a medium format camera, you get an instrument capable of imaging wide field regions of space with ultra-high resolution. Despite the fast focal ratio, no field flattener is required thanks to the one built in with the Petzval optical design.
Patented WIFD Focuser Design
Like most other William Optics telescopes, the Ultra-Cat 108 features the highly-regarded WIFD focuser. This focuser design moves all of the lens elements internally including the focuser drawtube, meaning there are no externally moving parts. This allows for much heavier imaging trains to be attached, greatly reducing tilt and vignetting. A built-in sensor tilt corrector is included in the rear of the telescope in case any tilt adjustments are necessary. The WIFD focuser is compatible with the popular ZWO EAF and other electronic focusers out of the box!
Precision Imaging Adjustments
Sensor Tilt Xterminator (STX)
The built-in STX allows quick side-access tilt adjustments without removing the camera.
Camera Angle Rotator
Correct any angular discrepancies, and get the perfect angle on your images.
Built-In Patented Bahtinov Mask
A Bahtinov Mask is built in to the front lens cover, allowing you to get ultra-sharp focus when you're on the go.
Patented Handle Bar Design
The Ultra-Cat 108 features the same extra-long handle bar found on other Cat-series telescopes, allowing for easy handling & attachment of accessories.
Specifications
- Lens Type: 5-Element Advanced Petzval
- Lens Elements: Super ED Glass x2, ED Glass x1, Lanthanum Glass x1, X-Element x1
- Focal Length: 518 mm
- Diameter: 108 mm
- Focal Ratio: f/4.8
- Image circle: 60 mm
- Focuser: WIFD R&P Focuser, Compatible with EAF
- Focuser Travel: 30 mm
- Included Adapters: Sensor Tilt Corrector, Rotator, M68, M54, M48 Camera Adapters
- Optional Flattener: No Flattener Required (built in)
- Maximum Available Backfocus: 65.7mm from the surface of the rotator (not sufficient for visual use with 1.25 in or 2 in diagonals)
- Filter Holder: None, so you will need to add a filter drawer or filter wheel for any imaging filters
- Camera Format: Medium Format, Full Frame, APS-C, M4/3
- Tube Length: 510.5 mm - 588.5 mm
- OTA Weight: 7.95 kg / 17.53 lbs
- Soft padded case included
- Maxiumum Backfocus: 65.7mm from M54 thread (rotator)
Other Information
- Country of Manufacture: Taiwan
Top-of-the-line Refractor for Astrophotography
Introducing the William Optics Ultra-Cat 108! This 5-element Petzval refractor features top-of-the-line components which enable sharp stars across a huge 60mm image circle. With a fast f/4.8 focal ratio and premium glass elements, this telescope is designed for the most demanding imagers.
60mm Image Circle: Medium Format Ready
The massive 60mm image circle means this telescope can support cameras with sensors as large as medium format. Full frame sensors are a breeze for the Ultra-Cat 108. William Optics have provided these impressive spot diagrams to prove its capabilities out to a 30mm radius, meaning it can handle the 55mm diagonal of medium format sensors with ease:
Premium Glass Elements
To produce a huge image circle with sharp stars like the Ultra-Cat 108 has, a telescope needs top-notch glass. The Ultra-Cat 108 features just that with a total of 5 impressive elements, including an ultra-premium Lanthanum glass element rarely found in this price range:
- Super ED Glass x2
- ED Glass x1
- Lanthanum Glass x1
- X-Element x1
Fast F/4.8 Focal Ratio
With a focal length of 518mm and an aperture of 108mm, the Ultra-Cat has a fast f/4.8 focal ratio which is perfect for many applications. When paired with a full frame or especially a medium format camera, you get an instrument capable of imaging wide field regions of space with ultra-high resolution. Despite the fast focal ratio, no field flattener is required thanks to the one built in with the Petzval optical design.
Patented WIFD Focuser Design
Like most other William Optics telescopes, the Ultra-Cat 108 features the highly-regarded WIFD focuser. This focuser design moves all of the lens elements internally including the focuser drawtube, meaning there are no externally moving parts. This allows for much heavier imaging trains to be attached, greatly reducing tilt and vignetting. A built-in sensor tilt corrector is included in the rear of the telescope in case any tilt adjustments are necessary. The WIFD focuser is compatible with the popular ZWO EAF and other electronic focusers out of the box!
Precision Imaging Adjustments
Sensor Tilt Xterminator (STX)
The built-in STX allows quick side-access tilt adjustments without removing the camera.
Camera Angle Rotator
Correct any angular discrepancies, and get the perfect angle on your images.
Built-In Patented Bahtinov Mask
A Bahtinov Mask is built in to the front lens cover, allowing you to get ultra-sharp focus when you're on the go.
Patented Handle Bar Design
The Ultra-Cat 108 features the same extra-long handle bar found on other Cat-series telescopes, allowing for easy handling & attachment of accessories.
Specifications
- Lens Type: 5-Element Advanced Petzval
- Lens Elements: Super ED Glass x2, ED Glass x1, Lanthanum Glass x1, X-Element x1
- Focal Length: 518 mm
- Diameter: 108 mm
- Focal Ratio: f/4.8
- Image circle: 60 mm
- Focuser: WIFD R&P Focuser, Compatible with EAF
- Focuser Travel: 30 mm
- Included Adapters: Sensor Tilt Corrector, Rotator, M68, M54, M48 Camera Adapters
- Optional Flattener: No Flattener Required (built in)
- Maximum Available Backfocus: 65.7mm from the surface of the rotator (not sufficient for visual use with 1.25 in or 2 in diagonals)
- Filter Holder: None, so you will need to add a filter drawer or filter wheel for any imaging filters
- Camera Format: Medium Format, Full Frame, APS-C, M4/3
- Tube Length: 510.5 mm - 588.5 mm
- OTA Weight: 7.95 kg / 17.53 lbs
- Soft padded case included
- Maxiumum Backfocus: 65.7mm from M54 thread (rotator)
| Manufacturer | William Optics |
|---|---|
| Telescope Focal Length | 501 - 600mm |
Top-of-the-line Refractor for Astrophotography
Introducing the William Optics Ultra-Cat 108! This 5-element Petzval refractor features top-of-the-line components which enable sharp stars across a huge 60mm image circle. With a fast f/4.8 focal ratio and premium glass elements, this telescope is designed for the most demanding imagers.
60mm Image Circle: Medium Format Ready
The massive 60mm image circle means this telescope can support cameras with sensors as large as medium format. Full frame sensors are a breeze for the Ultra-Cat 108. William Optics have provided these impressive spot diagrams to prove its capabilities out to a 30mm radius, meaning it can handle the 55mm diagonal of medium format sensors with ease:
Premium Glass Elements
To produce a huge image circle with sharp stars like the Ultra-Cat 108 has, a telescope needs top-notch glass. The Ultra-Cat 108 features just that with a total of 5 impressive elements, including an ultra-premium Lanthanum glass element rarely found in this price range:
- Super ED Glass x2
- ED Glass x1
- Lanthanum Glass x1
- X-Element x1
Fast F/4.8 Focal Ratio
With a focal length of 518mm and an aperture of 108mm, the Ultra-Cat has a fast f/4.8 focal ratio which is perfect for many applications. When paired with a full frame or especially a medium format camera, you get an instrument capable of imaging wide field regions of space with ultra-high resolution. Despite the fast focal ratio, no field flattener is required thanks to the one built in with the Petzval optical design.
Patented WIFD Focuser Design
Like most other William Optics telescopes, the Ultra-Cat 108 features the highly-regarded WIFD focuser. This focuser design moves all of the lens elements internally including the focuser drawtube, meaning there are no externally moving parts. This allows for much heavier imaging trains to be attached, greatly reducing tilt and vignetting. A built-in sensor tilt corrector is included in the rear of the telescope in case any tilt adjustments are necessary. The WIFD focuser is compatible with the popular ZWO EAF and other electronic focusers out of the box!
Precision Imaging Adjustments
Sensor Tilt Xterminator (STX)
The built-in STX allows quick side-access tilt adjustments without removing the camera.
Camera Angle Rotator
Correct any angular discrepancies, and get the perfect angle on your images.
Built-In Patented Bahtinov Mask
A Bahtinov Mask is built in to the front lens cover, allowing you to get ultra-sharp focus when you're on the go.
Patented Handle Bar Design
The Ultra-Cat 108 features the same extra-long handle bar found on other Cat-series telescopes, allowing for easy handling & attachment of accessories.
Specifications
- Lens Type: 5-Element Advanced Petzval
- Lens Elements: Super ED Glass x2, ED Glass x1, Lanthanum Glass x1, X-Element x1
- Focal Length: 518 mm
- Diameter: 108 mm
- Focal Ratio: f/4.8
- Image circle: 60 mm
- Focuser: WIFD R&P Focuser, Compatible with EAF
- Focuser Travel: 30 mm
- Included Adapters: Sensor Tilt Corrector, Rotator, M68, M54, M48 Camera Adapters
- Optional Flattener: No Flattener Required (built in)
- Maximum Available Backfocus: 65.7mm from the surface of the rotator (not sufficient for visual use with 1.25 in or 2 in diagonals)
- Filter Holder: None, so you will need to add a filter drawer or filter wheel for any imaging filters
- Camera Format: Medium Format, Full Frame, APS-C, M4/3
- Tube Length: 510.5 mm - 588.5 mm
- OTA Weight: 7.95 kg / 17.53 lbs
- Soft padded case included
- Maxiumum Backfocus: 65.7mm from M54 thread (rotator)
Other Information
- Country of Manufacture: Taiwan
| Manufacturer | William Optics |
|---|---|
| Telescope Focal Length | 501 - 600mm |
William Optics Ultra-Cat 108 f/4.8 WIFD Petzval Refractor Telescope