Celestron 94105 Neutral Density Moon Filter 1.25" 🔭

This neutral density moon filter helps reduce glare and improve contrast when observing bright lunar features, planets and close double stars. It is a compact accessory designed for use with 1.25 inch eyepieces, offering a simple way to dim overly bright views and reveal finer detail during high-contrast viewing sessions.

Key Points

The filter lowers transmission to about 13% of incoming light, which reduces glare and makes details on the Moon and bright planets easier to discern. This lower light level also helps when splitting tight double stars under bright conditions. 🌙

Made with an optical glass element set into an aluminium housing, the accessory threads onto any Celestron 1.25 inch eyepiece and can be stacked with colour filters for further fine-tuning of views. Its low weight and small size make it convenient to carry in a field kit or eyepiece case. 🔭

Consider that, according to the manufacturer, this level of attenuation is strong enough to darken very bright objects; it may not be necessary under dimmer skies or with smaller apertures where brightness is already moderate.

Technical Specifications

• Name: Celestron 94105 Neutral Density Moon Filter
• Transmission: 13% (allows approximately 13% of light through)
• Size: 31 mm x 11.5 mm (1.22" x 0.45")
• Weight: 0.21 oz (6 g)
• Compatibility: Fits 1.25" eyepieces by threading onto the ocular

Usage Recommendations

Screw the filter onto the eyepiece before inserting it into the focuser for the most secure fit. For planetary observing, try stacking the neutral density filter with a subtle colour filter to enhance contrast on specific features, or use it alone when the brightness of the Moon or Venus washes out details. When switching between targets of different brightness, remove or reapply the filter as needed rather than relying on magnification changes alone.

If you own multiple eyepieces, consider leaving one fitted with the filter for quick access during a session where targets vary in brightness. This accessory is compact enough to be carried in an eyepiece pouch without adding noticeable bulk.