Sky-Watcher StarTravel 150/750 OTA Refractor Telescope
Overview
The Sky-Watcher StarTravel 150/750 OTA is an achromatic refractor with a 150mm objective aperture and 750mm focal length, offering an outstanding combination of large aperture and short focal length. The resulting focal ratio of f/5.0 and an exceptionally wide field of view make this telescope one of the best instruments for observing large areas of the night sky. The tube is compact and lightweight, making it easy to transport and store without sacrificing optical performance. These qualities make it equally suitable for experienced observers and those just beginning their journey in astronomy.
What Can You Observe?
The wide field of view makes finding objects in the sky significantly easier - a quality especially valuable for beginners still learning their way around the stars. The telescope allows comfortable observation of the Moon, planets, and the Sun (with a suitable solar filter). However, it truly excels at observing:
- Extensive star fields and sections of the Milky Way
- Open star clusters
- Large emission and reflection nebulae
- Comets, especially those with broad tails that would be difficult to frame in a narrow field of view
- Faint deep-sky objects such as galaxies, planetary nebulae, and distant star clusters
- Variable stars, where the ability to capture fainter stars across a wider area is crucial
With suitable wide-angle eyepieces, it can deliver a field of view comparable to quality binoculars, but with significantly greater reach and light-gathering power typical of a telescope. The light-collecting ability is 459x greater than the naked eye, making it a highly effective tool even for faint targets.
Thanks to its compact dimensions and mechanical durability, the telescope can also be used for daytime nature observation.
Optics and Performance
The telescope is built around a classic two-element achromatic objective lens, ensuring high image quality and good correction of chromatic aberration for visual observation. Key optical performance figures include:
| Parameter |
Value |
| Aperture |
150 mm |
| Focal length |
750 mm |
| Focal ratio |
f/5.0 |
| Limiting stellar magnitude |
~13.5 mag |
| Angular resolution (Dawes) |
0.77″ |
| Angular resolution (Rayleigh) |
0.95″ |
| Maximum useful magnification |
300x |
| Light-gathering power vs. naked eye |
459x |
The 150mm aperture allows the telescope to reach objects as faint as approximately magnitude 13.5 - far beyond the limit of the human eye (approximately magnitude 6). The angular resolution of 0.77″ (Dawes) ensures that even tight double stars can be reliably split. Maximum useful magnification is 300x, though moderate magnifications combined with wide-angle eyepieces are optimal for most visual observing sessions.
Focuser and Mounting
The telescope features a 2″ rack-and-pinion focuser, which accepts a wide range of standard eyepieces and accessories. The tube is supplied with tube rings and a standard Vixen-format dovetail bar, allowing it to be mounted on most commonly available astronomical mounts - both alt-azimuth and equatorial - without any modifications.
Included Accessories
- 9x50 optical finder scope - wide aperture and broad field of view make target acquisition quick and easy
- Tube rings
- Vixen-format dovetail bar
Technical Specifications
| Parameter |
Value |
| Optical design |
Achromatic refractor |
| Objective aperture |
150 mm |
| Focal length |
750 mm |
| Focal ratio |
f/5.0 |
| Focuser diameter |
2″ |
| Focuser type |
Rack-and-pinion |
| Finder scope |
9x50 optical |
| Dovetail standard |
Vixen |
| Tube length |
650 mm |
| Tube weight |
6.6 kg |
| Total weight (with accessories) |
9.5 kg |
Who Is This Telescope For?
The Sky-Watcher StarTravel 150/750 OTA is an ideal choice for observers seeking a versatile, portable refractor with a large aperture at a reasonable price. It appeals to beginners thanks to its straightforward operation and wide field of view, while experienced amateur astronomers will appreciate it as a compact travel scope or a dedicated wide-field instrument. It is also well suited for astrophotography of wide-field targets when paired with a suitable motorized mount. The telescope is furthermore a welcome tool for astronomy clubs, schools, and educational institutions, thanks to its reliability and low maintenance requirements.
Key Advantages at a Glance
- Large 150mm aperture with compact, portable form factor
- Fast f/5.0 focal ratio - excellent for wide-field visual and photographic use
- Good chromatic aberration correction for visual observation
- 2″ rack-and-pinion focuser compatible with a wide range of eyepieces
- Includes 9x50 finder scope for easy target acquisition
- Vixen dovetail bar for compatibility with most astronomical mounts
- Suitable for beginners and experienced observers alike
- Low maintenance, durable construction
