CHF 6'299.00incl. Swiss VAT
Will be ordered for you
Timeframe: 10 days to 3 weeks
Estimated shipping: Between November 22 and 27, 2026
The Rainbow Astro RST-135 mount revolutionizes portable astrophotography thanks to its innovative technology, combining exceptional lightness, uncompromising precision, and versatility. Available in two versions—the standard RST-135 and the RST-135E, which is equipped with absolute encoders—it meets the diverse needs of both amateur astronomers and professional astrophotographers.
| Features | RST-135 | RST-135E (Absolute encoders) |
|---|---|---|
| Weight | 3.3 kg | 3.4 kg |
| Payload | 13.5 kg (without counterweight) | 13.5 kg (without counterweight) |
| Transmission | Harmonic Drive | Harmonic Drive |
| Absolute encoders | No | Yes (RA axis, Renishaw) |
| Engine | Swiss made Maxon DC High precision servo | Swiss made Maxon DC High precision servo |
| Periodic accuracy (PE) | Better than competitors | ± 2.5 arcsec, real-time correction via encoder |
| Recovery from power failure | Manual search required | Immediate automatic restart (absolute encoder) |
Harmonic Drive technology virtually eliminates mechanical play, resulting in exceptional precision when tracking celestial objects. Unlike traditional gear-driven mounts, it requires no mechanical play adjustment, thereby minimizing maintenance.
Thanks to its light weight and high load-bearing capacity without counterweight, the RST-135 is ideal for travelling astrophotographers looking for a quick, transportable set-up.
With a stated accuracy of ±2.5 arcseconds, this mount produces perfectly round stars at any focal length! You can use it without guiding, or with guiding, you’ll achieve exceptional performance!

| Criteria | RST-135 | RST-135E |
|---|---|---|
| Initial alignment time | ~5 min | ~2 min |
| Typical guidance error (RMS) | < 1 arcsec | < 0.5 arcsec |
| Resumption after interruption | Manual | Automatic |
Whether you’re an amateur astronomer looking for portability and ease of use or an experienced astrophotographer who demands flawless precision, the Rainbow Astro RST-135 mount is the perfect fit for your needs. Choose the RST-135E if you want to benefit from the highest precision offered by absolute encoders. Choosing Rainbow Astro means choosing excellence in astrophotography.
Ultra-compact harmonic mount for portable astrophotography: 13.5 kg without counterweights, 18 kg with counterweights, for a 3.3 to 3.4 kg head. Ideal for use with an 80 to 130 mm refractor. Recommended capacity for astrophotography: 13.5 kg, or 75 % of the advertised load, to maintain precise tracking.
Swiss Maxon motors, built-in GPS, and one of the best load-to-weight ratios on the market (approximately 4). E version: Renishaw encoder on the AD axis, periodic error reduced to ±2.5″.
No, up to 13.5 kg for the instrument. For weights above that and up to 18 kg, you'll need to add a bar and a counterweight.
The Rainbow RST-135E operates on 12 to 16 V DC. Current consumption: 0.2 A in tracking mode, 1 to 2 A in pointing mode (at 12 V). For neat wiring, the Pegasus Saddle Powerbox climbs onto the saddle with the'dedicated interface.
The Rainbow RST-135E is sold without a tripod. Choose a tripod or monopod that can support the total weight. A monopod extension with a long tube is recommended so that it does not touch your feet when framing shots near the pole.
The Rainbow RST-135E is controlled using a computer (ASCOM).