High-quality 1.25" diagonal eyepiece with an Amici prism set at a 45° angle. Thanks to its design, it provides an upright and non-inverted image, making it particularly useful for nature and landscape observations, as well as for orienting on maps.

Unlike many erecting prisms with a free aperture of only 19 mm, the Baader Planetarium model features a BaK-4 prism with a free aperture of 24 mm. This avoids vignetting when using longer focal length eyepieces and observing at low magnifications.

The attachment is compatible with the following telescopes:
• refractors
• catadioptric (Maksutow, Schmidt-Cassegrain)
• Cassegrain and Ritchey-Chrétien (RC) types

It is designed for optical instruments equipped with a 1.25" focuser, which require simple image orientation during terrestrial observations.

Technical parameters / key features

• deflection angle: 45°
• optical length of the cap: 99 mm
• prism material: BaK-4 with MC (Multi-Coated) anti-reflective coatings
• free prism clearance: 24 mm – no vignetting at low magnifications
• provides an upright and non-inverted image
• full internal reflection on the prism surface
• Inner diameter on the eyepiece/camera side: 1.25" (31.75 mm)
• inner diameter on the lens side: 1.4" thread (35.5 mm)
• Outer diameter from the lens side: 1.25" (31.75 mm)
• eyepiece mounting: locking screw + clamping ring protecting the eyepiece sleeve
• filter thread in the nose: yes, 1.25"
• weight: 154 g