Eyepiece Baader Classic Ortho 6mm 1.25 inch — Orthoscopic eyepiece, 6 mm focal length, 1.25-inch barrel

The Baader Classic Ortho 6mm 1.25" is an orthoscopic eyepiece with a 6 mm focal length and a standard 1.25-inch barrel. It is engineered for high-contrast, sharp views of planets, the Moon and close double stars. The design delivers a narrow, well-corrected apparent field of view that emphasizes fine detail and contrast, suitable for visual observing, planetary sketching and tight-field high-magnification work with telescopes that accept 1.25" eyepieces.

Advantages

The orthoscopic optical design provides high image contrast and minimal edge aberrations, producing crisp planetary disks and clear lunar terminator detail. The simple, classic layout yields a flat, well-corrected central field with reduced internal reflections and reliable mechanical compatibility with standard 1.25" focusers. Compact size and solid construction make the eyepiece stable in use and easy to exchange during an observing session.

Suitable for

• High-magnification planetary observing
• Lunar detail studies and sketching
• Double-star splitting and measurement
• Visual observers using 1.25" focusers who need high contrast

Key specifications

• Focal length: 6 mm
• Barrel diameter: 1.25 inches
• Optical type: Orthoscopic eyepiece
• Field of view: narrow, well-corrected apparent field optimized for high magnification
• Application: visual observing and planetary/lunar detail work

How to use

Install the eyepiece in any telescope focuser or diagonal that accepts 1.25" eyepieces. Use it at medium to high telescope focal ratios for best performance on planetary and lunar targets. Allow the instrument and eyepiece to reach thermal equilibrium before making fine focus adjustments. For bright targets, reduce eye fatigue by using an appropriate aperture stop or lower magnification eyepiece when needed, then switch to the 6 mm orthoscopic for detailed inspection and sketching.

Recommendations

For optimal results, pair the 6 mm orthoscopic with stable mounts and moderate to long focal length telescopes to achieve comfortable eye relief and peak contrast. Use precise focussing and steady seeing conditions to fully resolve planetary features and close double stars.