A gray filter manufactured by Baader Planetarium with a transmission of 25% and a diameter of ø=2". Designed for advanced and demanding users. Made with high precision and as the only gray filter in our offer covered with Phantom Group anti-reflection coatings, it does not show any reflections when observing bright objects. The filter's optical density is OD=0.6, which means a transmission of 25%. It is equipped with a standard 2" filter thread on both sides. The filter cell height is 8.2 mm (0.33"). The filter's active aperture is 45.8 mm (1.8").

Spectrally neutral gray filters can attenuate the light from very bright objects such as the Sun (NOTE: Must be used in conjunction with an ND5 solar filter), the Moon, planets, and bright stars. Attenuating the brightness of objects visible through the eyepiece allows for better resolution of visible details. The filter is suitable for lunar and planetary observations, as well as for resolving bright and close binary star systems. A 25% transmittance filter is best for observing the near-quarter Moon and the outer planets with a telescope exit pupil of less than 1 mm.

Technical parameters

• type: broadband, neutral density
• frame: 2"
• transmission: 25%
• substrate: glass
• layers: MC
• weight: 66 g

Guarantee

24 months