Solar Continuum Filter Baader 7.5 nm 2" — narrowband solar continuum filter for visual and imaging

The Baader Solar Continuum Filter 7.5 nm in 2" format is a narrowband optical filter designed to isolate a portion of the solar continuum suited for high-contrast visual observing and imaging of the Sun's photosphere. The filter fits standard 2" focusers and eyepiece holders, reducing the influence of spectral lines to emphasize surface detail such as granulation, faculae and sunspot penumbrae. It is intended for daytime use on refractors, reflectors and Maksutov/Cassegrain systems equipped for safe solar observation when used together with appropriate solar equipment.

Advantages

The 7.5 nm bandwidth provides a balance between contrast enhancement and image brightness, improving visibility of fine photospheric structure without excessive dimming. The 2" mounting format offers mechanical compatibility with common focusers and filter wheels, while optical coatings minimize reflections and preserve image quality. The filter's narrowband characteristic suppresses unwanted spectral features for clearer detail in both visual observation and solar astrophotography.

Suitable for

• High-contrast visual solar observing of photospheric detail
• Solar imaging with planetary or dedicated astro cameras
• Use with 2" eyepieces, diagonal holders and filter wheels
• Daytime observational sessions focused on granulation and sunspot structure

Key specifications

• Optical bandpass: 7.5 nm full width at half maximum (FWHM) centered on the solar continuum
• Mount size: 2-inch (for insertion into 2" focusers and eyepiece holders)
• Operation: Narrowband continuum filter for photospheric detail enhancement
• Compatibility: Designed for use in standard 2" optical train components
• Coatings: Anti-reflection and protective coatings to preserve contrast and transmission

How to use

Install the filter into a clean 2" focuser, diagonal or filter drawer following standard safety procedures for solar observing. Always ensure a proper full-aperture solar stop or dedicated solar filter is in place at the telescope aperture before any visual or imaging session; the continuum filter is not a primary solar aperture filter and must be used only after a safe front-aperture solar filter is installed. For visual use, insert a comfortable eyepiece after the continuum filter to observe granulation and sunspot detail. For imaging, place the filter in the optical path in front of the camera or within a 2" filter wheel and adjust exposure to compensate for reduced light due to the narrow bandpass.

Usage recommendations

Use the Baader 7.5 nm solar continuum filter in combination with a certified full-aperture solar filter and appropriate mounting to ensure observer and equipment safety. When imaging, start with short exposures and increase gradually while monitoring histogram and detail; for visual work, allow the eye to adapt and avoid prolonged direct staring even with proper filtration.