Eyepiece Skywatcher WA-66 15mm 1.25-inch – wide-angle ocular for telescopes

Skywatcher WA-66 15mm 1.25-inch eyepiece is a wide-angle ocular designed for telescopes with 1.25" focusers. The 15 mm focal length provides medium magnification that is suitable for both planetary and deep-sky observation. Multi-element optics create a 66° apparent field of view, offering a broad image with improved sharpness toward the edges and comfortable eye relief for extended viewing sessions.

Advantages

The WA-66 design combines a wide apparent field with a compact 1.25-inch barrel, enabling easier framing of extended objects and star fields. Multi-element glass and optimized coatings reduce reflections and increase contrast, while the moderate focal length balances detail and field size for diverse observing targets. The eyepiece construction ensures stable mounting in standard 1.25" focusers and provides predictable eye relief for observers who wear glasses.

Suitable for

• Planetary observation (Moon, Mars, Jupiter, Saturn)
• Deep-sky viewing of nebulae, star clusters and brighter galaxies
• Wide-field star hopping and locating objects
• Visual astronomy sessions that require comfortable eye relief

Key specifications

• Focal length: 15 mm
• Apparent field of view: 66°
• Barrel diameter: 1.25 inches
• Optical design: multi-element wide-angle ocular
• Eye relief: comfortable for extended observing (suitable for eyeglass wearers)

How to use

Insert the eyepiece into the 1.25" focuser or diagonal and secure it with the focuser thumbscrew. Begin with your telescope focused on a bright object, then fine-tune focus using small adjustments of the focuser. For best results, allow the telescope to reach thermal equilibrium and use a low- to medium-power setting when centering targets before switching to higher magnification if needed. Use the eyecup or adjust your eye position to find the full 66° apparent field and maintain comfortable viewing distance.

Usage recommendations

For improved contrast and reduced glare, use the eyepiece with a properly collimated telescope and avoid direct light into the objective. Store the eyepiece in a protective case when not in use and clean optical surfaces only with appropriate tools to preserve coatings and ensure long-term performance.