Eyepiece Beta Hyperion 13mm 2 inch/1.25 inch (MPN 2454613)

The Beta Hyperion 13mm eyepiece is a medium-power visual accessory designed for astronomical observation. It provides a 13 mm focal length and dual compatibility with 2" and 1.25" telescope focusers, allowing straightforward installation on a wide range of refractors, reflectors and catadioptric instruments. The optical design delivers comfortable eye relief and a clear field suitable for detailed observation of the Moon, planets and brighter deep-sky objects.

Advantages

This eyepiece combines the flexibility of dual barrel sizes with a compact focal length to support varied observation setups. Optical elements are configured to provide good edge-to-edge sharpness and minimized internal reflections for improved contrast. The comfortable eye relief accommodates users who wear glasses and helps reduce eye strain during extended observing sessions. Mechanical build allows secure mounting and easy switching between 2" and 1.25" focusers.

Suitable for

• Planetary and lunar observation at medium magnification
• General visual inspection of bright deep-sky objects (star clusters, nebulae)
• Use with both 2" and 1.25" focusers for versatile telescope compatibility
• Eyepiece sets where an intermediate focal length is required

Key specifications

• Focal length: 13 mm
• Barrel compatibility: 2" and 1.25" dual-mount
• Optical design: multi-element eyepiece optimized for visual use
• Field of view: wide apparent field for comfortable framing (manufacturer typical value)
• Eye relief: designed for comfortable viewing, including eyeglass wearers
• Construction: metal barrel with secure locking and smooth mechanical fit

How to use

Install the eyepiece by selecting the appropriate barrel size for the focuser, then insert and secure it using the focuser thumbscrews or compression ring. Allow the telescope to reach thermal equilibrium for sharper images, then focus carefully on the target using the telescope fine focus control. For planetary detail, start with a lower magnification eyepiece to locate the target and then switch to the 13 mm eyepiece for increased magnification. If using with a 2" diagonal or adapter, ensure any adapter is fully seated and tightened to avoid tilt or light leaks.

Recommendations

Use the eyepiece in stable atmospheric conditions for best results; avoid high magnification during poor seeing. Clean optical surfaces only with appropriate tools and fluids to preserve coatings. Combine with a Barlow lens or higher-power eyepieces to extend the range of usable magnifications when observing planets or small deep-sky objects.