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 €
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 €
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 €
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 days (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 days (valid for new orders)
