Bresser Kellner Eyepiece 4mm 1.25″

Bresser Eyepiece Kellner 4mm 1.25″ is a short focal length eyepiece that allows high magnifications. This can be interesting for trying details on the moon or planets, although the field of view is narrow and the viewing experience is less comfortable than with Plössl eyepieces. For serious planetary observations, a Plössl or Orthoscopic eyepiece is usually a better choice.

Observation goals
Only suitable with good seeing and larger telescopes. Especially useful as an entry-level option for moon and Jupiter.

Specifications

• Focal length: 4 mm
• Type: Kellner eyepiece
• Barrel size: 1.25″
• Field of view: approx. 40°
• Optical design: 3 elements, 2 groups
• Coating: Coated