RedCat 71 II
William Optics
From ~$1,449.46
2 stores
The William Optics RedCat 71 II is a premium 71mm Petzval astrograph featuring the innovative WIFD (William Optics Internal Focus Design) that moves lens elements internally rather than using a traditional external focuser, eliminating vignetting and sensor tilt issues. With its f/4.9 focal ratio and 350mm focal length, this apochromatic refractor delivers a flat field across a 45mm imaging circle without requiring an additional flattener, making it ideal for wide-field deep-sky imaging on full-frame cameras. The FPL-53 optical design provides exceptional color correction and pinpoint star quality, while the motorized focuser-compatible WIFD system and included M48/M54/M68 threads make it seamlessly compatible with modern astronomy cameras.
Specifications
| Total Weight with Rings and Dovetail | 3.7 kg |
| Tube Length | 435 mm |
| Optical design | Petzval Apochromatic |
| Aperture | 71 mm |
| Lens Elements | 4 |
| Back Focus Distance | 56 mm |
| Focuser Type | WIFD Helical Focuser with 2GT Gear Ring |
| Focal length | 350 mm |
| Glass Type | FPL-53 |
| Focal ratio | f/4.9 |
| OTA Weight | 2.8 lb |
| Field Flattener Required | false |
| Image Circle | 45 mm |
| Camera Mount Threads | M48, M54, M68 |