Optical tube Newton Astrograph ARTESKY ARTEC 250 E F/4.5

ARTESKY ARTEC 250 E F/4.5 Newton Tube Optical Astrograph ARTESKY ARTEC 250 E F/4.5

ARTESKY 's ARTEC astrograph series redefines telescope design by combining cutting-edge manufacturing techniques with world-class optical systems, ensuring exceptionally high quality standards.

The project emerged in 2011 from the vision of Stefano Seveso, founder of Artesky, and was developed in collaboration with engineer Flavio Simeone.

ARTEC was created to meet the needs of demanding astrophotographers who value stable collimation, high-quality optics and repeatability of results. The astrograph is not considered a stand-alone tool, but an integral component of a complete imaging system.

Over the years, the ARTEC series has evolved, with continuous improvements in both design and production.

Its generous dimensions make it ideal for fixed observatories or for expert astrophotographers on the move looking for dark skies and long-term stability. Thanks to its precise mechanics, collimation holds up better than typical Cassegrain systems of the same diameter.

Optical quality and coma correction

Each optical assembly is selected to ensure the overall accuracy of the telescope:

• Reflectivity > 95 %
• Correction of λ/8 or better
• Strehl's ratio ≥ 0.95

The quartz conical primary mirror ensures optimal thermal behavior, minimizing lateral shifts and optimizing cooling time.

The included 1.14x coma corrector provides a focal length of 1140 mm (f/4.56) and a fully illuminated 44 mm field, ideal for full-frame sensors.

Mechanical and cooling details

Three quiet 12V fans speed up the cooling of the mirror. All mounting screws are made of 316 stainless steel, hand-polished for corrosion resistance and attractive appearance.

Each unit is thoroughly tested prior to delivery to ensure compliance with Artesky's quality standards.

Precision mechanics and materials

Using advanced design software, each mechanical part is manufactured from CNC-milled 6061 aluminum and laser-cut components. The result is a rigid, stable, easy-to-use system that maintains collimation over long sessions.

All mechanical parts are made from lightweight aluminum, steel and bronze. The secondary support, laser-cut for maximum rigidity, ensures easy alignment. A special anodizing treatment protects against inclement weather.

Professional focuser and ROAS system

The 3" PegasusAstro Prodigy microfocuser, specifically adapted for ARTEC, supports up to 9.5 kg without flexing. A dedicated base with adjustable tilt connects the focuser to the OTA.

On the camera, the ROAS (Rotation On-Axis System) allows manual rotation and optimal alignment of the image train. Includes M54x0.75 male adapter; custom adapters are available upon request.

100% solid carbon fiber tube

Chosen not only for its weight, but also for its structural rigidity and thermal stability, the carbon fiber tube is manufactured by an Italian company specializing in aerospace-grade materials.

It is autoclave-treated, with a matte finish on the outside and a blackened interior coating with anti-dust and anti-reflective coating. Its roughened interior reduces moisture retention.

Elements included

• ARTEC 250 (L version)
• Mounting rings
• Dovetail bar Losmandy
• 3" Pegasus Prodigy electronic focuser
• 1.14x coma corrector
• ROAS system with M54x0.75 adapter
• Protective cardboard packaging

Technical Specifications

• Optical assembly: Newtonian astrograph
• Diameter: 250 mm
• Primary mirror diameter: 255 mm
• Secondary mirror diameter: 100 mm
• Focal length: 1000 mm - 1140 mm with coma corrector included
• Focal Ratio: F/4.0 - F/4.56 with included coma corrector
• Mirror material: Quartz
• Linear obstruction: 30
• Illuminated field: 44 mm including coma corrector
• Dimensions: 921 mm (length) x 310 mm (width) x 480 mm (height)
• Weight: 19.7 kg
• Tube material: High-end carbon fiber
• Mechanical material: 6061 aluminum

Optical tube Newton Astrograph ARTESKY ARTEC 250 E F/4.5