Omegon Apochromatic Refractor Pro APO AP 71/490 Quadruplet OTA (85631)

Omegon Apochromatic Refractor Pro APO AP 71/490 Quadruplet OTA (85631)

The Omegon Pro APO AP 71/490 Quadruplet is designed for astrophotographers who want sharper images, accurate colours and a flat, fully illuminated field. Its advanced optical design allows you to capture the night sky with greater detail and contrast, revealing structures and tones that simpler optics often fail to show.

This 71 mm apochromatic refractor uses a quadruplet lens system with premium ED glass to achieve excellent colour correction and image sharpness. The integrated field corrector delivers a flat image circle suitable even for full-frame cameras, ensuring stars remain crisp from the centre to the edges of the frame.

All lens elements are fully multi-coated to reduce reflections and increase contrast. Compared with many reflector systems, this refractor provides highly defined planetary views and detailed deep-sky images with minimal chromatic aberration.

Precision Focusing System

The telescope features a robust 2.5-inch rack-and-pinion focuser with 1:10 fine reduction. Its hybrid design combines gear-driven precision with smooth ball-bearing support, allowing stable focusing even with heavy camera setups up to 4 kg. The large diameter prevents vignetting, making it well suited for modern imaging sensors.

The focuser is compatible with Omegon Pro Focus Motor Estia, ZWO Electronic Automatic Focuser EAF N and iOptron Electronic Automatic Focuser iEAF without requiring additional adapters.

A 360° rotating mechanism allows you to adjust the camera orientation easily, ensuring precise framing without disturbing focus. The 2-inch eyepiece adapter can be removed to reveal an M64x0.75 female thread beneath.

Optical Specifications

Type: Refractor
Design: Apochromat
Aperture: 71 mm
Focal length: 490 mm
Focal ratio: f/6.9
Resolving power: 1.94 arcseconds
Limiting magnitude: 12.3
Light-gathering power: 100x
Maximum useful magnification: 142x
Lens design: Quadruplet
Fully corrected field: 44 mm

Mechanical Details

Focuser type: Rack and pinion
Eyepiece connection: 2-inch (adapters for 1.25-inch included)
Fine focusing: 1:10 reduction
Focusing travel: 50 mm
Rotatable focuser: Yes
Motorized: No
Ring clamp: Yes

Tube Specifications

Tube weight: 3.0 kg
Total weight: 4.7 kg
Length: 373 mm
Dew cap diameter: 93 mm
Dew shield: Included
Integrated corrector: Yes
Prism rail: Vixen-style
Finder base: Vixen/Skywatcher level
Tube clamps: Included
Extension tubes: Included

Included deviating optics: 1.25-inch Amici prism (45°)
Included eyepieces: 1.25-inch, 8 mm and 20 mm

Transport case: Not included

Applications

Astrophotography: Yes
Moon and planets: Yes
Nature observation: Yes
Nebulae and galaxies: Yes
Solar observation: No

Recommended For

Beginners: No
Advanced users: Yes
Observatories: No

Series: Pro APO
Variant: Flat-Field