TS-Optics Imaging Star 70 OTA This 70 mm four-element flat-field refractor has a 474 mm focal length and f/6.78 focal ratio. It is intended for visual astronomy and astrophotography with the appropriate camera train.
Manufacturer model: TS-Optics Imaging Star 70 OTA · Specifications checked against manufacturer data on 2026-11-04
This 70 mm four-element flat-field refractor has a 474 mm focal length and f/6.78 focal ratio. It is intended for visual astronomy and astrophotography with the appropriate camera train.
The front objective is an FPL51/lanthanum doublet, followed by a separate two-element corrector inside the tube. The 2.5-inch RAP focuser terminates in M54 × 0.75.
The built-in corrector provides a manufacturer-specified 32 mm flat field. Working distance from the 2-inch socket is 135 mm. Tube mass including accessories is 2.8 kg; minimum length is 370 mm.
TS-Optics manufacturer documentation
Four-element flat-field design is a two-element SD objective plus a separate built-in two-element corrector. It is not a four-element front objective. Field diameter 32 mm is manufacturer stated.
| Corrected and flattner field | 32 mm with 100% correction |
|---|---|
| Working distance from the 2 receptacle | 135 mm |
| Tube weight incl accessories | 2.8 kg |
| Outer dimensions transport case | 45 x 23 x 19.5 cm (LxWxH) |
Data sheet
Specific References
TS-Optics Imaging Star 70 OTA This 70 mm four-element flat-field refractor has a 474 mm focal length and f/6.78 focal ratio. It is intended for visual astronomy and astrophotography with the appropriate camera train.
Manufacturer model: TS-Optics Imaging Star 70 OTA · Specifications checked against manufacturer data on 2026-11-04
