Orion Optics UK VX8L Optical Tube Assembly
- 200mm Primary Mirror Diameter
- 1200mm Focal Length (f/6)
- Standard 1/6 PV Wavefront Optics
- 8kg Nominal Tube Weight
- CNC 9-Point Mirror Cell with Cooling Fan
- 2" Focuser with Reduction Gearing
Simulate the exact field of view of the Orion Optics UK VX8L Optical Tube Assembly with your specific telescope.
Launch Visual Assistant
Simulate the exact field of view of the Orion Optics UK VX8L Optical Tube Assembly with your specific telescope.
Launch Imaging AssistantThe Orion Optics UK VX8L Optical Tube Assembly pairs a 200mm primary mirror with a 1200mm (f/6) focal length, delivering high-resolution views in a lightweight 8kg package. Every VX8L is built around a primary mirror hand-figured to a guaranteed 1/6 PV wavefront accuracy, a standard verified by Zygo interferometer testing. The OTA's physical design includes a 1130mm long aluminum tube, a 50mm secondary mirror, and a CNC-machined 9-point mirror cell for exceptional optical stability.
Unlike mass-produced instruments, the VX8L's primary mirror is certified to a minimum 1/6 PV wavefront accuracy. This figure isn't an estimate; it's a measured value from a Zygo laser interferometer, with the report supplied for your specific optic. This level of precision ensures that the light cone converges more accurately, translating directly into higher contrast on planetary details, tighter star points, and the ability to resolve finer structures in nebulae and galaxies.
The 200mm primary mirror rests on a CNC-machined 9-point flotation cell, which distributes the mirror's weight evenly to prevent sagging and induced astigmatism as the telescope moves. An integrated cooling fan accelerates thermal equilibrium, reducing tube currents for steadier views. At a nominal weight of just 8kg, the 1130mm aluminum tube is manageable for a wide range of equatorial mounts, offering significant aperture without requiring a massive support system.
The VX8L is equipped with a 2" focuser featuring reduction gearing, allowing for both coarse and fine focus adjustments. This dual-speed control is critical for achieving sharp focus at high magnifications on planetary targets or when using a camera for astrophotography. The larger 2" barrel accommodates wide-field eyepieces for sweeping views of star fields, and an included adapter steps down to fit standard 1.25" accessories.
While the standard 1/6 PV optic delivers superb performance, Orion Optics UK offers optional upgrades for the most demanding observers. The choice depends entirely on your primary observing goals.
The images below show the same view of Saturn captured through each available optical grade, under identical conditions -- a visual illustration of how each step up in wavefront accuracy sharpens contrast and fine detail.
1/6 PV (Professional)
1/8 PV (Research)
1/10 PV (Ultra)
1/6 PV wavefront refers to the Peak-to-Valley error of the optical surface, measured against a perfect theoretical curve. A smaller fraction indicates a more accurate mirror. This high standard, verified by a Zygo interferometer, ensures that the VX8L produces sharper stars and higher image contrast compared to typical mass-produced telescopes that do not specify a wavefront error guarantee.
The 1200mm focal length at f/6 provides a versatile field of view. With a low-power 2" eyepiece, you can easily frame large objects like the Andromeda Galaxy (M31) or the Orion Nebula (M42). While not as wide as a short-tube refractor, the f/6 ratio offers a good balance, providing enough magnification to resolve details in galaxies and nebulae without making the field of view too restrictive.
You should consider an upgrade if your primary focus is high-resolution planetary or lunar observing and imaging. While the standard 1/6 PV optic is excellent, the 1/8 PV and 1/10 PV upgrades provide a measurable increase in contrast and sharpness. This allows you to resolve finer details like Jupiter's cloud belts, the Cassini Division in Saturn's rings, or subtle lunar rilles more clearly, especially during nights of good seeing.
The VX8L optical tube has a nominal weight of 8kg. This makes it compatible with mid-range equatorial mounts rated for payloads of approximately 13kg (28 lbs) or more, such as a Sky-Watcher HEQ5 or Celestron AVX. This relatively low weight for a 200mm Newtonian makes it a portable and accessible option for many amateur astronomers.
The CNC 9-point mirror cell provides uniform support for the 200mm primary mirror. This prevents the glass from flexing under its own weight as the telescope's orientation changes, which would otherwise introduce optical distortions like astigmatism. This robust support system is critical for maintaining the high-quality images the hand-figured optics are capable of producing.
Absolutely. The combination of a 200mm aperture and guaranteed 1/6 PV optics makes the VX8L an excellent planetary instrument. At its 1200mm focal length, using a quality Barlow lens and eyepiece will allow you to push magnification to see details like Jupiter's Great Red Spot, shadow transits of its moons, and multiple cloud bands, assuming steady atmospheric conditions.
| Optical Design | Newtonian Reflector |
| Primary Mirror Diameter | 200mm |
| Focal Length | 1200mm |
| Focal Ratio | f/6 |
| Standard Optics Grade | 1/6 PV wavefront |
| Optics Upgrade Options | 1/8 PV and 1/10 PV Ultra |
| Secondary Mirror Size | 50mm |
| Focuser | 2" focuser with reduction gearing |
| Mirror Cell | CNC 9 point |
| Mirror Cooling | Integrated Fan |
| Tube Material | Aluminium |
| Tube Diameter | 225mm |
| Tube Length | 1130mm |
| Tube Weight | 8kg (nominal) |