Pentax SMC XL 8-24mm (JIS Class 4, weather-resistant) eyepiece (12338)

This zoom eyepiece is designed for astronomers who value both optical performance and comfort during extended viewing sessions. It features up to eight lens elements arranged in four groups, with all internal surfaces fully blackened to reduce internal reflections. The use of ED-glass, including Lanthanum elements, helps minimize chromatic aberration and ensures balanced light transmission. Additional lens elements are included to reduce the spherical aberration of the human eye, helping to prevent the "black-out" effect and providing a more stable image.

The eyepiece offers an apparent field of view between 38° and 60°, and a comfortable eye relief of 20 mm, making it suitable for users with or without eyewear. Its weatherproof JIS 4 rating protects it from moisture, dew, and outdoor conditions. The twist-up rubber eyecup adds extra comfort and adaptability for different users.

Key Features:

• Up to 8 lens elements in 4 groups, with fully blackened interiors to minimize reflections

• ED-glass and Lanthanum elements to reduce chromatic aberration and optimize light transmission

• Extra lens elements to reduce the "black-out" effect caused by spherical aberration of the human eye

• Apparent field of view ranges from 38° to 60° for maximum usability and comfort

• Eye relief of 20 mm for comfortable viewing, even with glasses

• JIS 4 weatherproof rating for protection against moisture and dew

• Twist-up rubber eyecup for adjustable comfort

Specifications:

• Focal length: 8 mm (zoom range 8–24 mm)

• Eye relief: 15 mm (sector 11–15 mm)

• Apparent field of view: 60° (sector 38–60°)

• Number of lenses: 6

• Number of groups: 4

• Telescope connection: 1.25"

• Optical system coating: Multiple coatings

• Filter thread: Yes

• Inert gas charge: No

• Series: XL

• Weight: 550 g

• Length: 144 mm

• Type: Eyepiece

• Build: Zoom eyepiece

This eyepiece combines advanced optics, user comfort, and weather resistance, making it a versatile choice for both casual and serious astronomers.