Boren-Simon N 200/568 8″ PowerNewton Astrograph OTA Telescope - Only tube with accessories, without mounting, without tripod

Boren-Simon N 200/568 8″ PowerNewton Astrograph OTA

If you are looking for a telescope that delivers fast, high-quality astrophotography without compromise, the Boren-Simon N 200/568 PowerNewton Astrograph OTA is exactly what you need. This 8″ Newtonian with a focal length of 568 mm and a focal ratio of f/2.8 (with reducer/corrector applied) is designed to minimise exposure times, maintain a sharp image across the entire field of view, and remain compact enough for portable mounts. It is a mature instrument for astrophotographers who want to get the most out of their equipment - whether shooting from a dark site or right from the glow of city lights.

Optics and field corrector

Both the primary and secondary mirrors feature 94% reflectivity, ensuring excellent light throughput and high contrast in the resulting images. The key component of the entire system is the professional 4-element ED NEXUS reducer/corrector, which reduces the focal length from the base 600 mm to 568 mm and sets the focal ratio to f/2.8. Thanks to this corrector, the telescope achieves outstanding sharpness across the entire field of view right into the corners of an APS-C sensor - free from coma, star spikes or chromatic aberrations typical of cheaper solutions.

The working distance of the corrector is 55 mm from the M48 thread, allowing easy adaptation to common astro cameras and DSLR cameras. The precise focal plane position is 66.85 mm from the corrector, making focus repeatable and predictable.

Visual use

For visual observation, the focal plane is located 140 mm above the tube. For comfortable use with standard eyepieces, it is recommended to add a 50 mm extension tube. This is a minor compromise that is entirely normal for fast Newtonian astrographs and does not affect photographic performance in any way.

Carbon tube and mechanical construction

The tube is made of carbon fibre with a diameter of 230 mm, keeping the total weight of the instrument at just 7.6 kg with a length of 790 mm. These figures will be appreciated by owners of portable mounts - for example, the Sky-Watcher EQ6-R or iOptron CEM40 will carry this astrograph with comfortable capacity left for a camera and filter wheel. The carbon tube also has minimal thermal expansion, so temperature changes during the night have less impact on focus accuracy.

Focuser

The TS UNCN2-G2 dual-speed focuser with a 2″ drawtube and 1:10 reduction ratio allows fine focusing without vibration - particularly valued when working with heavier cameras. The focuser design eliminates camera tilt, which would otherwise cause uneven sharpness across the sensor. The focuser is fully compatible with motorised units such as the ZWO EAF, making it easy to integrate the entire system into an automated workflow with software-controlled autofocus (N.I.N.A., Sequence Generator Pro and others).

Narrowband and light-polluted sky photography

The f/2.8 focal ratio combined with support for narrowband filters (H-alpha, OIII, SII) opens the door to astrophotography even under heavily light-polluted skies. Short exposures reduce the impact of atmospheric turbulence and enable quality imaging even with uncooled DSLR cameras, where thermal noise at longer exposures would otherwise complicate post-processing. For narrowband imaging from suburban locations, this astrograph is a genuinely practical solution.

About the Boren-Simon PowerNewton series

Boren-Simon PowerNewton astrographs have earned a solid reputation among astrophotographers who refuse to compromise on optical quality. The PowerNewton series is the result of collaboration between experienced astronomers and optical engineers who place emphasis on repeatable mechanical precision, high mirror reflectivity and truly functional field correctors - not just claimed on paper, but verified in real-world use. Whether you photograph nebulae, galaxies or planetary nebulae, Boren-Simon provides an instrument you can rely on night after night.

Technical specifications