SQA55 Quintuplet Refractor
Askar
From $695.00
2 stores
In stock
The Askar SQA55 is a compact 55mm quintuplet Petzval refractor designed for both astrophotography and daytime telephoto work, featuring a 264mm focal length and f/4.8 wide-open aperture. With its self-flattened optical design combining ED and SD glass elements, it delivers sharp stars from edge to edge with no external field flattener required, making it ideal for full-frame deep-sky imaging of nebulae and star clusters. The telescope uniquely features manual focus rings with dual-speed control and a variable aperture adjustable from f/4.8 to f/22, combined with quick-release mounts and a portable 2.18kg package.
Specifications
| Aperture | 55 mm |
| Field Flatness | Self-flattened (50-60mm backfocus range) |
| Total Weight | 2.18 kg |
| Focal Ratio (Wide Open) | f/4.8 |
| Corner Star RMS Radius | 4 μm |
| Filter Thread (Rear) | M48 |
| Total Length (without dew shield) | 244 mm |
| Edge Illumination | 90% |
| OTA Weight | 1.84 lb |
| Focal Ratio Range | 4.8 to 22 |
| Image Circle | 44 mm |
| Glass Elements | 1 SD glass, 1 ED glass |
| Closest Focusing Distance | 5 ft |
| Aperture Blades | 14 |
| Focal length | 264 mm |
| Central Star RMS Radius | 2.5 μm |
| Filter Thread (Objective) | 67 mm |
| Total Length (with dew shield) | 316 mm |
| Optical design | Quintuplet Air-Spaced Petzval APO |
| Focus Mode | Manual helical with dual-speed (coarse and fine) |