OTA · MSRP $2,698
William Optics Cat 91 WIFD · 30th Anniversary Limited Edition
Key specifications
| Aperture | 91 mm |
|---|---|
| Focal length | 448 mm |
| Focal ratio | f/4.9 |
| Optical design | Other |
| Back focus | 60.8 mm |
| Weight | 4.72 kg |
All specifications
| Focuser type | WIFD rack-and-pinion, EAF compatible, 0-36 mm travel |
|---|---|
| Tube length | 556 mm |
| Dovetail | Vixen |
About
A 91 mm f/4.9 five-element advanced Petzval astrograph needing no flattener, covering a 55 mm image circle. Built on the WIFD rack-and-pinion focuser with 36 mm of travel, supplied with a tilt adjuster, rotator and M63 to M54/M48 adapters, on a Vixen dovetail. A commemorative 30th anniversary edition in red.