CAT Series
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CAT Series
From the beginning, the goal was to create the best possible design for an affordable, small, lightweight, and fast Apochromatic refactor for astrophotography.
Characteristics:
- 4 lens Petzval optical design
- Aperture 51mm, focal lenght 250mm, f/4.9
- Massive OTA from Aluminum alloy
- Compact and ultra portable
- Field rotator
- Helical focuser design
- Tilting platform
- Field illumination even for full frame sensors
999.00 € 949.05 €
Estimated delivery time : 1-4 weeks (valid for new orders)
William offers with the REDCAT61 Astrograph a very well corrected telescope for astrophotography up to full frame format.
- Aperture 61 mm / Focal length 300 mm / Focal ratio f/4.9
- Petzval design with chromatic aberration free FPL53 objective (4 elements in 3 groups)
- Very well corrected and illuminated image field up to full frame format - the corrector is built in - no more adapter battle necessary
- Camera connection via M48 male thread (suitable adapters are available) - working distance 55 mm
- 360° rotation of the camera for the right display window
- Focusing via internal focusing (William Internal Focus Design - WIFD) as with telephoto lenses
- Tilting option for individual adjustment of the camera sensor to the telescope
- Flexible dovetail bar at the base (long version), suitable for Vixen style and Arca-Swiss saddle plates, in addition with 1/4" female photo tripod thread
- Nylon carrying bag and Bahtinov mask for astrophotography are included in delivery
1899.00 € 1804.05 €
Estimated delivery time : 3-4 weeks (valid for new orders)
![William RedCat 71WIFD - 71 mm f/4,9 Flatfieldrefraktor für Astrofotografie [REDCAT71WIFD]](https://www.apm-telescopes.net/images/thumbs/0655527_william-redcat-71wifd-71-mm-f49-flatfieldrefraktor-fur-astrofotografie-redcat71wifd_640.jpeg "William RedCat 71WIFD - 71 mm f/4,9 Flatfieldrefraktor für Astrofotografie [REDCAT71WIFD]")
William offers with the RedCat 71 WIFD astrograph a very well corrected telescope for astrophotography up to full frame format.
- Aperture 71 mm / Focal length 350 mm / Focal ratio f/4.9
- Petzval design with chromatic aberration free FPL53 objective (4 elements in 3 groups)
- Very well corrected and illuminated image field up to full frame format - the corrector is built in - no more adapter battle necessary
- Camera connection via M48 male thread (suitable adapters are available) - working distance 55 mm
- 360° rotation of the camera for the right display window
- Focusing via internal focusing (William Internal Focus Design - WIFD) as with telephoto lenses
- Tilting option for individual adjustment of the camera sensor to the telescope
- Flexible dovetail bar at the base (long version), suitable for Vixen style and Arca-Swiss saddle plates, in addition with 1/4" female photo tripod thread
- Nylon carrying bag and Bahtinov mask for astrophotography are included in delivery
- WIFD R&P focuser - copatible with EAF
1490.00 € 1415.50 €
Estimated delivery time : 1-4 days (valid for new orders)
The Ultra-Cat 56 is a high-performance 56 mm apochromatic refractor, designed for astrophotographers who demand exceptional clarity and true color accuracy.
- Aperture 56 mm, focal length 269 mm
- Focal ratio f/4.8
- Optical design according to Petzval with integrated corrector (five elements in total)
- No flattener necessary
- Temperature-stable lens cells
- Clear and sharp image even when using a full frame sensor
- William Optics Internal Focus Design (WIFD)
- 30 mm focuser travel
- Rotator and tilt flange included
- Patented multifunctional handle
- Connection on camera side: M54, M48
1398.00 €
Estimated delivery time : 1-4 weeks (valid for new orders)
The Ultra-Cat 76 is a powerful apochromatic 76 mm refractor designed for astrophotographers who demand very high sharpness and color fidelity.
- Aperture ratio 1:4.8
- Petzval optical design with integrated corrector (five elements in total)
- Temperature-stable lens cells
- Color-pure and sharp imaging even when using a full-frame sensor
- William Optics Internal Focus Design (WIFD)
- Rotator and tilt flange included
- Patented multifunctional handle
- Camera-side connection: M54, M48
2290.00 €
Estimated delivery time : 1-4 weeks (valid for new orders)
The William Optics Ultra-Cat 131 · 30th Anniversary Limited Edition is an instrument for those who not only want to observe, but also want to hold history in their hands. This anniversary model combines the technical maturity of three decades of William Optics development with an aesthetic that will make collectors' hearts beat faster. The combination of a five-element Petzval design, Super ED glass and precise mechanical workmanship makes it one of the most powerful compact astrographs in its class
6608.00 € 6277.60 €
Estimated delivery time : 3-4 weeks (valid for new orders)
The William Optics Ultra-Cat 131 · 30th Anniversary Limited Edition is an instrument for those who not only want to observe, but also want to hold history in their hands. This anniversary model combines the technical maturity of three decades of William Optics development with an aesthetic that will make collectors' hearts beat faster. The matching ZWO AM7 Parallactic Harmonic Drive GoTo mount with pier is also available.
13590.00 € 12910.50 €
Estimated delivery time : 3-4 weeks (valid for new orders)
